BMA250 SHUTL

BMA250 BMA250 sensor Digital, triaxial acceleration Data sheet Bosch Sensortec Data sheet Bosch Sensortec BMA250 Data sheet Ordering code Please contact your Bosch Sensortec representative for the ordering code Package type 12-pin LGA Document revision 1.15 Document release date 31 May 2012 Document number BST-BMA250-DS002-05 Technical reference code(s) 0 273 141 121 Notes Rev. 1.15 Data in this document are subject to change without notice. Product photos and pictures are for for illustration purposes only and may 31 differ from- 2012 the real Page 1 / not publishing - May product‟s appearance. © Bosch Sensortec GmbH reserves allNot rights even in the of industrial property rights. We reserve all rights of disposal such intended forevent publishing. as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec BMA250 Digital, triaxial 2g to 16g acceleration sensor with intelligent on-chip motion-triggered interrupt controller Key features • • • • • • Ultra-Small package LGA package (12 pins), footprint 2mm x 2mm, height 0.95mm Digital interface SPI (4-wire, 3-wire), I²C, 2 interrupt pins VDDIO voltage range: 1.2V to 3.6V Programmable functionality Acceleration ranges ±2g/±4g/±8g/±16g Low-pass filter bandwidths 1kHz - 0V). To switch off the interface supply (VDDIO = 0V) and keep the internal supply on (VDD > 0V) is safe only in normal mode. If the device is in low-power mode or suspend mode while VDDIO = 0V, there is a risk of excess current consumption on the VDD supply (non-destructive). It is absolutely prohibited to keep any interface at a logical high level when V DDIO is switched off. Such a configuration will permanently damage the device (i.e. if VDDIO = 0  [SDI & SDO & SCK & CSB] ≠ high). The device contains a power-on reset (POR) generator. It resets the logic part and the register values after powering-on VDD and VDDIO. There is no limitation on the sequence of switching on Rev. 1.15 Page 10 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet both supply voltages. In case the I²C interface shall be used, a direct electrical connection between VDDIO supply and the PS pin is needed in order to ensure reliable protocol selection (see section 4.2 Operational modes). 4.2 Operational modes Depending on the configuration the BMA250 is able to operate in two different operational modes:  General mode: The device is acting as a slave on a digital interface (SPI or I²C) and is controlled by the external bus master (e.g. µC). The master gets measurement data and status information from the device through the digital interface. In particular, the master can configure the interrupt controller and read out the interrupt status registers. Moreover, it can freely configure and use the two interrupt pins (INT1, INT2). Several interrupts may be enabled in parallel.  Dedicated mode: The dedicated mode allows the sensor to be operated as a standalone device in a simple µC-less system without abandon of the interrupt functionality. No digital interface is needed and, as a consequence, no measurement data can be read from the device. Instead of the digital interface the internal interrupt engine with its default setting is used. The interrupt status is mapped onto dedicated output pins. One out of three different sub-modes can be chosen: A) orientation recognition, B) tap sensing or C) slope (any-motion) detection. Only one interrupt at a time can be assigned. The selection of the operational mode is done during start-up or reset by the state of the PS pin. If PS is floating, the dedicated mode is selected. A defined digital state selects the general mode. All pads are in input mode (no output driver active) during the start-up sequence until the operational mode and, in case of the general mode, the interface type is selected. The start-up sequence is run after power-up and after reset. Figure 2 illustrates the selection of the different operational modes: reset yes PS floating? Dedicated Mode no General Mode check configuration pins no Table 4 & Table 5 PS = 0? yes Sub-Mode A Sub-Mode B Sub-Mode C Orientation Sens. Tap Sens. Slope Sens. Orientation Interrupt is enabled Tap sensing Interrupt is enabled Any-Motion Interrupt is enabled General Mode with I²C General Mode with SPI One or more interrupts can be configured via I²C One or more interrupts can be configured via SPI Figure 2: Operational mode selection Rev. 1.15 Page 11 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 4.2.1 General mode A defined digital state at the PS pin selects the general mode. Its polarity determines the kind of interface to be used:    PS = GND PS = VDDIO PS = float enables the digital SPI interface enables the digital I²C interface enables the dedicated mode 4.2.2 Dedicated mode (µC-less or stand-alone mode) The dedicated mode operates with pre-defined settings of the interrupt engine in order to generate the motion-triggered interrupt-signals, i.e. bandwidth, sleep time, low-power mode, threshold, and hysteresis are use case optimized. Nevertheless some minor configurations can be selected by the user. The dedicated mode is entered if the device is connected according to table 3. During the start-up / power on sequence the PS pin (#11) must float. Table 3: Entering and operating dedicated mode VDDIO NC VDD GNDIO GND PS Pin#3 Pin#4 Pin#7 Pin#8 Pin#9 Pin#11 VDDIO NC VDD GND GND float Depending on the configuration of the other device pins according to table 4 the corresponding sub-mode of the dedicated mode is entered. In table 4 and table 5 the unshaded entries represent necessary input values for the corresponding sub-mode selection while the shaded entries represent corresponding output parameters of the events to be detected. Table 4: Sub-mode selection and specific outputs of the dedicated mode Sub-Mode Orientation Tap Slope SDO SDx INT1 INT2 CSB SCx Pin#1 Pin#2 Pin#5 Pin#6 Pin#10 Pin#12 GND output output output output select orient1-detect orient0-detect orient2-detect flat-detect orient sleep output output GND double-detect single-detect GND output motion-detect VDD select select tap type tap sleep GND select slope sleep VDD VDD Table 5 contains state and description details of the parameters introduced in table 4. Unshaded entries represent input values to be set, shaded entries represent output parameters to be detected. Rev. 1.15 Page 12 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Table 5: Description of the parameters of table 4 Sub-Mode Parameter State Description see Table 4 output orient0-detect output orient1-detect Orientation BW = 62.5 Hz output orient2-detect output flat-detect select orient sleep output double-detect output Tap single-detect BW = 1k Hz select tap type select tap sleep output Slope motion-detect BW = 125 Hz select slope sleep low high low high low high low high GND VDD low high low high GND VDD GND VDD low high GND VDD “upright” for portrait / “left” for landscape “upside-down” for portrait / “right” for landscape portrait landscape z-axis upward looking i.e. || < 90° (Fig. 8) z-axis downward looking i.e. || > 90° (Fig. 8) non flat i.e. || > 19,5° (Fig. 8) flat i.e. || < 19,5° (Fig. 8) Low-Power mode enabled, sleep time = 100ms Low-Power mode enabled, sleep time = 1s currently no Double-Tap event Double-Tap event detected currently no single-tap event Single-Tap event detected Single-Tap detection enabled Double-Tap detection enabled Low-Power Mode disabled Low-Power Mode enabled, sleep time = 10ms currently no Any-Motion event Any-Motion event detected Low-Power mode enabled, sleep time = 50ms Low-Power mode enabled, sleep time = 1s low = GND, high = VDDIO For more details, refer to chapter 4.3 Power modes and 4.8 Interrupt Controller  Orientation recognition sub mode  refer to chapter 4.8.7  Tap sensing sub mode  refer to chapter 4.8.6  Any-motion (slope) detection) sub mode  refer to chapter 4.8.5 Rev. 1.15 Page 13 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 4.3 Power modes The BMA250 has three different power modes. Besides normal mode, which represents the fully operational state of the device, there are two special energy saving modes: low-power mode and suspend mode. The possible transitions between the power modes are illustrated in figure 3: Power off Normal Mode Low-Power Mode Suspend Mode Figure 3: Power mode transition diagram In normal mode, all parts of the electronic circuit are held powered-up and data acquisition is performed continuously. In contrast to this, in suspend mode the whole analog part, oscillators included, is powered down. No data acquisition is performed, the only supported operations are reading registers (latest acceleration data are kept) and writing to the (0x11) suspend bit or (0x14) softreset register. Suspend mode is entered (left) by writing ´1´ (´0´) to the (0x11) suspend bit. In low-power mode, the device is periodically switching between a sleep phase and a wake-up phase. The wake-up phase essentially corresponds to operation in normal mode with complete power-up of the circuitry. During the sleep phase the analog part except the oscillators is powered down. Low-power mode is entered (left) by writing ´1´ (´0´) to the (0x11) lowpower_en bit. During the wake-up phase the number of samples required by any enabled interrupt is processed. If an interrupt is detected, the device stays in the wake-up phase as long as the interrupt condition endures (non-latched interrupt), or until the latch time expires (temporary interrupt), or until the interrupt is reset (latched interrupt). If no interrupt is detected, the device enters the sleep phase. The duration of the sleep phase is set by the (0x11) sleep_dur bits as shown in the following table: Rev. 1.15 Page 14 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Table 6: Sleep phase duration settings (0x11) sleep_dur 0000b 0001b 0010b 0011b 0100b 0101b 0110b 0111b 1000b 1001b 1010b 1011b 1100b 1101b 1110b 1111b Sleep Phase Duration tsleep 0.5ms 0.5ms 0.5ms 0.5ms 0.5ms 0.5ms 1ms 2ms 4ms 6ms 10ms 25ms 50ms 100ms 500ms 1s The current consumption of the BMA250 can be calculated according to this formula: I DDlp  t sleep  I DDsm  t active  I DD t sleep  t active . When making an estimation about the length of the wake-up phase tactive, the wake-up time, tw_up, has to be considered. Therefore, tactive = tut + tw_up, where tut is given in table 8. During the wake-up phase all analog modules are held powered-up, while during the sleep phase most analog modules are powered down. As a consequence, a wake-up time of less than 1ms (typ. value 0.8ms) is needed to settle the analog modules in order to get reliable acceleration data. Table 7 gives an overview of the resulting average supply currents IDDlpe for the different sleep phase durations and a selected bandwidth of 1000Hz, assuming no interrupt is active and thus only one sample per wake-up phase is taken: Rev. 1.15 Page 15 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec Table 7: Average current consumption in low-power mode Sleep phase duration 0.5ms 1ms 2ms 4ms 6ms 10ms 25ms 50ms 100ms 500ms 1s Average current consumption 100.5 µA 78.8 µA 55.0 µA 34.5 µA 25.2 µA 16.4 µA 7.4 µA 4.0 µA 2.3 µA 0.9 µA 0.7 µA 4.4 Sensor data 4.4.1 Acceleration data The width of acceleration data is 10 bits given in two´s complement representation. The 10 bits for each axis are split into an MSB upper part (one byte containing bits 9 to 2) and an LSB lower part (one byte containing bits 1 and 0 of acceleration and a (0x02, 0x04, 0x06) new_data flag). Reading the acceleration data registers shall always start with the LSB part. The content of an MSB register is updated by reading the corresponding LSB register (shadowing procedure). The shadowing procedure can be disabled (enabled) by writing ´1´ (´0´) to the bit shadow_dis. With disabled shadowing, the content of both MSB and LSB registers is updated by a new value immediately. Unused bits of the LSB registers are fixed to 0. The (0x02, 0x04, 0x06) new_data flag of each LSB register is set if the data registers are updated, it is reset if either the corresponding MSB or LSB part is read. Two different streams of acceleration data are available, unfiltered and filtered. The unfiltered data is sampled with 2kHz. The sampling rate of the filtered data depends on the selected filter bandwidth; it is twice the bandwidth. Which kind of data is stored in the acceleration data registers depends on bit (0x13) data_high_bw. If (0x13) data_high_bw is ´0´ (´1´), then filtered (unfiltered) data is stored in the registers. Both data streams are separately offsetcompensated. Both kinds of data can be processed by the interrupt controller. Rev. 1.15 Page 16 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet The bandwidth of filtered acceleration data is determined by setting the (0x10) bw bit as followed: Table 8: Bandwidth configuration bw Bandwidth 00xxx 01000 01001 01010 01011 01100 01101 01110 01111 1xxxx *) 7.81Hz 15.63Hz 31.25Hz 62.5Hz 125Hz 250Hz 500Hz 1000Hz *) Update Time tut 64ms 32ms 16ms 8ms 4ms 2ms 1ms 0.5ms - *) Note: Settings 00xxx result in a bandwidth of 7.81 Hz; settings 1xxxx result in a bandwidth of 1000 Hz. It is recommended to actively use the range from ´01000b´ to ´01111b´ only in order to be compatible with future products. The BMA250 supports four different acceleration measurement ranges. A measurement range is selected by setting the (0x0F) range bits as follows: Table 9: Range selection Range 0011 0101 1000 1100 others Acceleration measurement range ±2g ±4g ±8g ±16g reserved Resolution 3.91mg/LSB 7.81mg/LSB 15.62mg/LSB 31.25mg/LSB - 4.4.2 Temperature data The width of temperature data is 8 bits given in two´s complement representation. Temperature values are available in the (0x08) temp register. The slope of the temperature sensor is 0.5K/LSB, its center temperature is 24°C [(0x08) temp = 0x00]. Therefore, the typical temperature measurement range is -40°C up to 87.5°C. Rev. 1.15 Page 17 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 4.5 Self-test This feature permits to check the sensor functionality by applying electrostatic forces to the sensor core instead of external accelerations. By actually deflecting the seismic mass, the entire signal path of the sensor can be tested. Activating the self-test results in a static offset of the acceleration data; any external acceleration or gravitational force applied to the sensor during active self-test will be observed in the output as a superposition of both acceleration and self-test signal. The self-test is activated individually for each axis by writing the proper value to the (0x32) self_test_axis bits (´01b´ for x-axis, ´10b´ for y-axis, ´11b´ for z-axis, ´00b´ to deactivate selftest). It is possible to control the direction of the deflection through bit (0x32) self_test_sign. The excitation occurs in positive (negative) direction if (0x32) self_test_sign = ´0b´ (´1b´). In order to ensure a proper interpretation of the self-test signal it is recommended to perform the self-test for both (positive and negative) directions and then to calculate the difference of the resulting acceleration values. Table 10 shows the minimum differences for each axis. The actually measured signal differences can be significantly larger. Table 10: Self-test difference values resulting minimum difference signal x-axis signal y-axis signal z-axis signal +0.8 g +0.8 g +0.4 g It is recommended to perform a reset of the device after self-test. If the reset cannot be performed, the following sequence must be kept to prevent unwanted interrupt generation: disable interrupts, change parameters of interrupts, wait for at least 600 s, enable desired interrupts. 4.6 Offset compensation Offsets in measured signals can have several causes but they are always unwanted and disturbing in many cases. Therefore, the BMA250 offers an advanced set of four digital offset compensation methods which are closely matched to each other. These are slow, fast, and manual compensation, and inline calibration. The compensation is performed for unfiltered and filtered data independently. It is done by adding a compensation value to the acceleration data coming from the ADC. The result of this computation is saturated if necessary to prevent any overflow errors (the smallest or biggest possible value is set, depending on the sign). However, the public registers used to read and write compensation values have only a width of 8 bits. An overview of the offset compensation principle is given in figure 4: Rev. 1.15 Page 18 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet bit_12 bit_11 bit_10 bit_9 bit_8 bit_7 bit_6 bit_5 bit_4 bit_3 bit_2 bit_1 bit_0 public register internal register offset_filt_x/y/z or offset_unfilt_x/y/z (8bit) offset_filt_full_x/y/z or offset_unfilt_x/y/z (10bit) acceleration data range: ±2g ±4g add to sign (msb) 500mg 250mg 125mg 62.5mg 31.3mg 15.6mg 7.8mg (lsb) 8bit – 10bit conversion sign (msb) 1g 500mg 250mg 125mg 62.5mg 31.3mg 15.6mg 7.8mg 3.9mg (lsb) sign (msb) sign (msb) 2g 1g 1g 500mg 500mg 250mg 250mg 125mg 125mg 62.5mg 62.5mg 31.3mg 31.3mg 15.6mg 15.6mg 7.8mg 7.8mg 3.9mg ±8g sign (msb) 4g 2g 1g 500mg 250mg 125mg 62.5mg 31.3mg 15.6mg ±16g sign (msb) 8g 4g 2g 1g 500mg 250mg 125mg 62.5mg 31.3mg compute compensation value Figure 4: Principle of offset compensation The meaning of both public and internal registers is the same for all acceleration measurement ranges. Therefore, with measurement ranges other than ±2g, one or more lower significant bits of the internal registers are lost when added to an acceleration value, or are set to zero when the internal compensation value is computed. If a compensation value is too small or too big to fit into the corresponding internal register, it is saturated to prevent an overflow error. In a similar way the conversion of the internal register value to the public register value (10bit to 8bit) uses saturation. Summarized, in dependence to the measurement range which has been set, the compensation value, which has been written into the public register will correct the data output according to figure 4. e.g. ±2g range: public register = 00000001b  add to acceleration data = ±7.8mg public register = 00000010b  add to acceleration data = +15.6mg public register = 00000101b  add to acceleration data = +39.1mg = +2LSB = +4LSB = +10LSB The public registers are image registers of EEPROM registers. With each image update (see section 4.7 Non-volatile memory for details) the contents of the non-volatile EEPROM registers are written to the public registers. At any time the public register can be over-written by the user. After changing the contents of the public registers by either an image update or manually, all 8bit values are widened to 10bit values and stored in the corresponding internal registers. In the opposite direction, if the value of an internal register changes due to the computation performed by a compensation algorithm, it is converted to an 8bit value and stored in the public register. Rev. 1.15 Page 19 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet For slow and fast offset compensation, the compensation target can be chosen by setting the bits (0x37) offset_target_x, (0x37) offset_target_y, and (0x37) offset_target_z according to table 11: Table 11: Offset target settings (0x37) offset_target_x/y/z 00b 01b 10b 11b Target value 0g +1g -1g 0g By writing ´1´ to the (0x36) offset_reset bit, all offset compensation registers are reset to zero. 4.6.1 Slow compensation Slow compensation is a quasi-continuous process which regulates the acceleration value of each axis towards the target value by comparing the current value with the target and adding or subtracting a fixed value depending on the comparison. The algorithm in detail: If an acceleration value is larger (smaller) than the target value (0x37) offset_target_x/y/z for a number of samples (given by the parameter Offset Period see table 12), the internal offset compensation value (0x38, 0x039, 0x3A) offset_filt_x/y/z or (0x3B, 0x03C, 0x3D) offset_unfilt_x/y/z is decremented (incremented) by 4 LSB. The public registers (0x38, 0x039, 0x3A) offset_filt_x/y/z and (0x3B, 0x03C, 0x3D) offset_unfilt_x/y/z are not used for the computations but they are updated with the contents of the internal registers (using saturation if necessary) and can be read by the user. The compensation period offset_period is set by the (0x37) cut_off bit as represented in table 12: Table 12: Compensation period settings (0x37) cut_off 0b 1b Offset Period 8 16 The slow compensation can be enabled (disabled) for each axis independently by setting the bits (0x36) hp_x_en, hp_y_en, hp_z_en to ´1´ (´0´), respectively. Slow compensation should not be used in combination with low-power mode. In low-power mode the conditions (availability of necessary data) for proper function of slow compensation are not fulfilled. Rev. 1.15 Page 20 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 4.6.2 Fast compensation Fast compensation is a one-shot process by which the compensation value is set in such a way that when added to the raw acceleration, the resulting acceleration value of each axis equals the target value. The algorithm in detail: An average of 16 consecutive acceleration values is computed and the difference between target value and computed value is written to (0x38, 0x39, 0x3A) offset_filt_x/y/z or (0x3B, 0x3C, 0x3D) offset_unfilt_x/y/z The public registers (0x38, 0x39, 0x3A) offset_filt_x/y/z and (0x3B, 0x3C, 0x3D) offset_unfilt_x/y/z are updated with the contents of the internal registers (using saturation if necessary) and can be read by the user. Fast compensation is triggered for each axis individually by setting the (0x36) cal_trigger bits as shown in table 13: Table 13: Fast compensation axis selection (0x36) cal_trigger 00b 01b 10b 11b Selected Axis none x y z The register (0x36) cal_trigger keeps its non-zero value while the fast compensation procedure is running. Slow compensation is blocked as long as fast compensation endures. Bit (0x36) cal_rdy is ´0´ when (0x36) cal_trigger is not ´00´. Fast compensation should not be used in combination with low-power mode. In low-power mode the conditions (availability of necessary data) for proper function of fast compensation are not fulfilled. 4.6.3 Manual compensation As explained above, the contents of the public compensation registers (0x38, 0x39, 0x3A) offset_filt_x/y/z and (0x3B, 0x3C, 0x3D) offset_unfilt_x/y/z can be set manually via the digital interface. It is recommended to write into these registers immediately after a new data interrupt in order not to disturb running offset computations. Writing to the offset compensation registers is not allowed if slow compensation is enabled or if the fast compensation procedure is running. 4.6.4 Inline calibration For a given application, it is often desirable to calibrate the offset once and to store the compensation values permanently. This can be achieved by using one of the aforementioned offset compensation methods to determine the proper compensation values and then storing Rev. 1.15 Page 21 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec these values permanently in the non-volatile memory (EEPROM). See section 4.7 Non-volatile memory for details of the storing procedure. Each time the device is reset, the compensation values are loaded from the non-volatile memory into the image registers and used for offset compensation until they are possibly overwritten using one of the other compensation methods. 4.7 Non-volatile memory The entire memory of the BMA250 consists of three different kinds of registers: hard-wired, volatile, and non-volatile. Non-volatile memory is implemented as EEPROM. Part of it can be both read and written by the user. Access to non-volatile memory is only possible through (volatile) image registers. Altogether, there are eight registers (bytes) of EEPROM which are accessible by the customer. The addresses of the image registers range from 0x38 to 0x3F. While the addresses up to 0x3D are used for offset compensation (see 4.6 Offset Compensation), addresses 0x3E and 0x3F are general purpose registers not linked to any sensor-specific functionality. The content of the EEPROM is loaded to the image registers after a reset (either POR or softreset) or after a user request which is performed by writing ´1´ to bit (0x33) nvm_load. As long as the image update is not yet complete, bit (0x33) nvm_load is ´1´, otherwise it is ´0´. The image registers can be read and written like any other register. Writing to the EEPROM is a three-step procedure: 1. Write the new contents to the image registers. 2. Write ´1´ to bit (0x33) nvm_prog_mode in order to unlock the EEPROM. 3. Write ´1´ to bit (0x33) nvm_prog_trig and keep ´1´ in bit (0x33) nvm_prog_mode in order to trigger the write process. Writing to the EEPROM always renews the entire EEPROM contents. It is possible to check the write status by reading bit (0x33) nvm_rdy. While (0x33) nvm_rdy = ´0´, the write process is still enduring; if (0x33) nvm_rdy = ´1´, then writing is completed. As long as the write process is ongoing, no power mode change and no image update is allowed. It is forbidden to write to the EEPROM while the image update is running, in low-power mode, and in suspend mode. 4.8 Interrupt controller Seven interrupt engines are integrated in the BMA250. Each interrupt can be independently enabled and configured. If the condition of an enabled interrupt is fulfilled, the corresponding status bit is set to ´1´ and the selected interrupt pin is activated. There are two interrupt pins, INT1 and INT2; interrupts can be freely mapped to any of these pins. The pin state is a logic ´or´ combination of all mapped interrupts. The interrupt status registers are updated together with writing new data into the acceleration data registers. If an interrupt is disabled, all active status bits and pins are immediately reset. Rev. 1.15 Page 22 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec All time constants are based upon the typical frequency of the internal oscillator. This is reflected by the bandwidths (bw) as specified in table 1. 4.8.1 General features An interrupt is cleared depending on the selected interrupt mode, which is common to all interrupts. There are three different interrupt modes: non-latched, latched, and temporary. The mode is selected by the (0x21) latch_int bits according to table 14 Table 14: Interrupt mode selection (0x21) latch_int 0000b 0001b 0010b 0011b 0100b 0101b 0110b 0111b 1000b 1001b 1010b 1011b 1100b 1101b 1110b 1111b Interrupt mode non-latched temporary, 250ms temporary, 500ms temporary, 1s temporary, 2s temporary, 4s temporary, 8s latched non-latched temporary, 500µs temporary, 500µs temporary, 1ms temporary, 12.5ms temporary, 25ms temporary, 50ms latched An interrupt is generated if its activation condition is met. It can not be cleared as long as the activation condition is fulfilled. In the non-latched mode the interrupt status bit and the selected pin (the contribution to the ´or´ condition for INT1 and/or INT2) are cleared as soon as the activation condition is no more valid. Exceptions to this behaviour are the new data, orientation, and flat interrupts, which are automatically reset after a fixed time. In the latched mode an asserted interrupt status and the selected pin are cleared by writing ´1´ to bit (0x21) reset_int. If the activation condition still holds when it is cleared, the interrupt status is asserted again with the next change of the acceleration registers. In the temporary mode an asserted interrupt and selected pin are cleared after a defined period of time. The behaviour of the different interrupt modes is shown graphically in figure 5: Rev. 1.15 Page 23 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec internal signal from interrupt engine interrupt output non-latched latch period temporary latched Figure 5: Interrupt modes Several interrupt engines can use either unfiltered or filtered acceleration data as their input. For these interrupts, the source can be selected with the respective (0x1E) int_src_... bits, in details these are (0x1E) int_src_data, (0x1E) int_src_tap, (0x1E) int_src_slope, (0x1E ) int_src_high, and (0x1E) int_src_low. Setting the respective bits to ´0´ (´1´) selects filtered (unfiltered) data as input. For the other interrupts, orientation recognition and flat detection, such a selection is not possible. They always use filtered input data. It is strongly recommended to set interrupt parameters prior to enabling the interrupt. Changing parameters of an already enabled interrupt may cause unwanted interrupt generation and generation of a false interrupt history. A safe way to change parameters of an enabled interrupt is to keep the following sequence: disable the desired interrupt, change parameters, wait for at least 600 s, enable the desired interrupt. 4.8.2 Mapping (inttype to INT Pin#) The mapping of interrupts to the interrupt pins #05 or #06 is done by registers (0x19) to (0x1B). Setting (0x19) int1_”inttyp” to ´1´ (´0´) maps (unmaps) “inttyp” to pin #5 (INT1), correspondingly setting (0x1B) int2_”inttyp” to ´1´ (´0´) maps (unmaps) “inttyp” to pin #6 (INT2). Note: “inttyp” to be replaced with the precise notation, given in the memory map in chapter 5. Example: For flat interrupt (int1_flat): Setting (0x19) int1_flat to ´1´ maps int1_flat to pin #5 (INT1). 4.8.3 Electrical behaviour (INT pin# to open-drive or push-pull) Both interrupt pins can be configured to show desired electrical behaviour. The ´active´ level of each pin is determined by the (0x20) int1_lvl and (0x20) int2_lvl bits. If (0x20) int1_lvl = ´1´ (´0´) / (0x20) int2_lvl = ´1´ (´0´), then pin #05 (INT1) / pin #06 (INT2) is active ´1´ (´0´). In addition to that, also the electric type of the interrupt pins can be selected. By Rev. 1.15 Page 24 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet setting bits (0x20) int1_od / (0x20) int2_od to ´0´, the interrupt pin output type gets push-pull, by setting the configuration bits to ´1´, the output type gets open-drive. Remark: Due to their use for sub-mode selection in dedicated mode, the states of both INT pins are not defined during the first 2 ms after power-up. 4.8.4 New data interrupt This interrupt serves for synchronous reading of acceleration data. It is generated after storing a new value of z-axis acceleration data in the data register. The interrupt is cleared automatically when the next cycle of data acquisition starts. The interrupt status is ´0´ for at least 50µs. The interrupt mode of the new data interrupt is fixed to non-latched. It is enabled (disabled) by writing ´1´ (´0´) to bit (0x17) data_en. The interrupt status is stored in bit (0x0A) data_int. 4.8.5 Any-motion (slope) detection Any-motion detection uses the slope between successive acceleration signals to detect changes in motion. An interrupt is generated when the slope (absolute value of acceleration difference) exceeds a preset threshold. It is cleared as soon as the slope falls below the threshold. The principle is made clear in figure 6. acceleration acc(t0) acc(t0−1/(2*bw)) time slope(t0)=acc(t0)−acc(t0−1/(2*bw)) slope slope_th time slope_dur slope_dur INT time Figure 6: Principle of any-motion detection Rev. 1.15 Page 25 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec The threshold is set with the value of register (0x28) slope_th. 1 LSB of (0x28) slope_th corresponds to 1 LSB of acceleration data. Therefore, an increment of (0x28) slope_th is 3.91 mg in 2g-range (7.81 mg in 4g-range, 15.6 mg in 8g-range and 31.3 mg in 16g-range). And the maximum value is 996 mg in 2g-range (1.99g in 4g-range, 3.98g in 8g-range and 7.97g in 16grange). The time difference between the successive acceleration signals depends on the selected bandwidth and equates to 1/(2*bandwidth) (Δt=1/(2*bw)). In order to suppress failure signals, the interrupt is only generated (cleared) if a certain number N of consecutive slope data points is larger (smaller) than the slope threshold given by (0x28) slope_th. This number is set by the (0x27) slope_dur bits. It is N = (0x27) slope_dur + 1 for (0x27). Example: (0x27) slope_dur = 00b, …, 11b = 1decimal, …, 4decimal 4.8.5.1 Enabling (disabling) for each axis Any-motion detection can be enabled (disabled) for each axis separately by writing ´1´ (´0´) to bits (0x16) slope_en_x, (0x16) slope_en_y, (0x16) slope_en_z. The criteria for any-motion detection are fulfilled and the slope interrupt is generated if the slope of any of the enabled axes exceeds the threshold (0x28) slope_th for [(0x27) slope_dur +1] consecutive times. As soon as the slopes of all enabled axes fall or stay below this threshold for [(0x27) slope_dur +1] consecutive times the interrupt is cleared unless interrupt signal is latched. 4.8.5.2 Axis and sign information of any motion interrupt The interrupt status is stored in bit (0x09) slope_int. The any-motion interrupt supplies additional information about the detected slope. The axis which triggered the interrupt is given by that one of bits (0x0B) slope_first_x, (0x0B) slope_first_y, (0x0B) slope_first_z that contains a ´1´. The sign of the triggering slope is held in bit (0x0B) slope_sign. If (0x0B) slope_sign = ´0´ (´1´), the sign is positive (negative). 4.8.5.3 Serial interface and dedicated wake-up mode When serial interface is active, any-motion detection logic is enabled if any of the axis specific (0x16) slope_en_... register bits are set. To disable the any-motion interrupt, clear all the axis specific (0x16) slope_en_... bits. In the dedicated wake-up mode (see chapter 4.2.2), all three axes are enabled for any-motion detection whether the individual axis enable bits are set or not. 4.8.6 Tap sensing Tap sensing has a functional similarity with a common laptop touch-pad or clicking keys of a computer mouse. A tap event is detected if a pre-defined slope of the acceleration of at least one axis is exceeded. Two different tap events are distinguished: A „single tap‟ is a single event within a certain time, followed by a certain quiet time. A „double tap‟ consists of a first such event followed by a second event within a defined time frame. Only one of the tap interrupts can be enabled at the same time. Single tap interrupt is enabled (disabled) by writing ´1´ (´0´) to bit (0x16) s_tap_en. Double tap interrupt is enabled (disabled) by writing ´1´ (´0´) to bit (0x16) d_tap_en. If one tries to enable both interrupts by writing ´1´ to Rev. 1.15 Page 26 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet (0x16) s_tap_en and (0x16) d_tap_en, then only (0x16) d_tap_en keeps the value ´1´ and the double tap interrupt is enabled. The status of the single tap interrupt is stored in bit (0x09) s_tap_int, the status of the double tap interrupt is stored in bit (0x09) d_tap_int. The slope threshold for detecting a tap event is set by bits (0x2B) tap_th. The meaning of (0x2B) tap_th depends on the range setting. 1 LSB of (0x2B) tap_th corresponds to a slope of 62.5mg in 2g-range, 125mg in 4g-range, 250mg in 8g-range, and 500mg in 16g-range. In figure 7 the meaning of the different timing parameters is visualized: slope 1st tap 2nd tap tap_th time tap_shock tap_quiet tap_dur tap_shock tap_quiet single tap detection 12.5 ms time double tap detection 12.5 ms time Figure 7: Timing of tap detection The parameters (0x2A) tap_shock and (0x2A) tap_quiet apply to both single tap and double tap detection, while (0x2A) tap_dur applies to double tap detection only. Within the duration of (0x2A) tap_shock any slope exceeding (0x2B) tap_th after the first event is ignored. Contrary to this, within the duration of (0x2A) tap_quiet no slope exceeding (0x2B) tap_th must occur, otherwise the first event will be cancelled. Rev. 1.15 Page 27 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 4.8.6.1 Single tap detection A single tap is detected and the single tap interrupt is generated after the combined durations of (0x2A) tap_shock and (0x2A) tap_quiet, if the corresponding slope conditions are fulfilled. The interrupt is cleared after a delay of 12.5 ms. 4.8.6.2 Double tap detection A double tap is detected and the double tap interrupt is generated if an event fulfilling the conditions for a single tap occurs within the set duration in (0x2A) tap_dur after the completion of the first tap event. The interrupt is cleared after a delay of 12.5 ms. 4.8.6.3 Selecting the timing of tap detection For each of parameters (0x2A) tap_shock and (0x2A) tap_quiet two values are selectable. By writing ´0´ (´1´) to bit (0x2A) tap_shock the duration of (0x2A) tap_shock is set to 50 ms (75 ms). By writing ´0´ (´1´) to bit (0x2A) tap_quiet the duration of (0x2A) tap_quiet is set to 30 ms (20 ms). The length of (0x2A) tap_dur can be selected by setting the (0x2A) tap_dur bits according to table 15: Table 15: Selection of tap_dur (0x2A) tap_dur 000b 001b 010b 011b 100b 101b 110b 111b length of tap_dur 50 ms 100 ms 150 ms 200 ms 250 ms 375 ms 500 ms 700 ms 4.8.6.4 Axis and sign information of tap sensing The sign of the slope of the first tap which triggered the interrupt is stored in bit (0x0B) tap_sign (´0´ means positive sign, ´1´ means negative sign). The value of this bit persists after clearing the interrupt. The axis which triggered the interrupt is indicated by bits (0x0B) tap_first_x, (0x0B) tap_first_y, and (0x0B) tap_first_z. The bit corresponding to the triggering axis contains a ´1´ while the other bits hold a ´0´. These bits are cleared together with clearing the interrupt status. Rev. 1.15 Page 28 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 4.8.6.5 Tap sensing in low power mode In low-power mode, a limited number of samples is processed after wake-up to decide whether an interrupt condition is fulfilled. The number of samples is selected by bits (0x2B) tap_samp according to table 16. Table 16: Meaning of (0x2B) tap_samp (0x2B) tap_samp 00b 01b 10b 11b Number of Samples 2 4 8 16 4.8.7 Orientation recognition The orientation recognition feature informs on an orientation change of the sensor with respect to the gravitational field vector „g‟. The measured acceleration vector components with respect to the gravitational field are defined as shown in figure 8. z  x j y g Figure 8: Definition of vector components Therefore, the magnitudes of the acceleration vectors are calculated as follows: acc_x = 1g∙sin∙cosj acc_y = −1g∙sin∙sinj acc_z = 1g∙cos → acc_y/acc_x = −tanj Rev. 1.15 Page 29 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Depending on the magnitudes of the acceleration vectors the orientation of the device in the space is determined and stored in the three (0x0C) orient bits. These bits may not be reset in the sleep phase of low-power mode. There are three orientation calculation modes with different thresholds for switching between different orientations: symmetrical, high-asymmetrical, and low-asymmetrical. The mode is selected by setting the (0x2C) orient_mode bits as given in table 17. Table 17: Orientation mode settings (0x2C) orient_mode 00b 01b 10b 11b Orientation Mode symmetrical high-asymmetrical low-asymmetrical symmetrical For each orientation mode the (0x0C) orient bits have a different meaning as shown in table 18 to table 20: Table 18: Meaning of the (0x0C) orient bits in symmetrical mode (0x0C) orient x00 Name Angle Condition portrait upright 315° < j < 45° x01 portrait upside down 135° < j < 225° x10 landscape left 45° < j < 135° x11 landscape right 225° < j < 315° |acc_y| < |acc_x| - „hyst‟ and acc_x - „hyst‟’ ≥ 0 |acc_y| < |acc_x| - „hyst‟ and acc_x + „hyst‟ < 0 |acc_y| ≥ |acc_x| + „hyst‟ and acc_y < 0 |acc_y| ≥ |acc_x| + „hyst‟ and acc_y ≥ 0 Table 19: Meaning of the (0x0C) orient bits in high-asymmetrical mode Rev. 1.15 (0x0C) orient x00 Name Angle Condition portrait upright 297° < j < 63° x01 portrait upside down 117° < j < 243° x10 landscape left 63° < j < 117° x11 landscape right 243° < j < 297° |acc_y| < 2∙|acc_x| - „hyst‟ and acc_x - „hyst‟ ≥ 0 |acc_y| < 2∙|acc_x| - „hyst‟ and acc_x + „hyst‟ < 0 |acc_y| ≥ 2∙|acc_x| + „hyst‟ and acc_y < 0 |acc_y| ≥ 2∙|acc_x| + „hyst‟ and acc_y ≥ 0 Page 30 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Table 20: Meaning of the (0x0C) orient bits in low-asymmetrical mode (0x0C) orient x00 Name Angle Condition portrait upright 333° < j < 27° x01 portrait upside down 153° < j < 207° x10 landscape left 27° < j < 153° x11 landscape right 207° < j < 333° |acc_y| < 0.5∙|acc_x| - „hyst‟ and acc_x - „hyst‟ ≥ 0 |acc_y| < 0.5∙|acc_x| - „hyst‟ and acc_x + „hyst‟ < 0 |acc_y| ≥ 0.5∙|acc_x| + „hyst‟ and acc_y < 0 |acc_y| ≥ 0.5∙|acc_x| + „hyst‟ and acc_y ≥ 0 In the preceding tables, the parameter „hyst‟ stands for a hysteresis, which can be selected by setting the (0x0C) orient_hyst bits. 1 LSB of (0x0C) orient_hyst always corresponds to 62.5 mg, in 2g-range, 125 mg in 4g-range, 250 mg in 8g-range and 500 mg in 16g-range.. It is important to note that by using a hysteresis ≠ 0 the actual switching angles become different from the angles given in the tables since there is an overlap between the different orientations. The most significant bit of the (0x0C) orient bits (which is displayed as an ´x´ in the above given tables) contains information about the direction of the z-axis. It is set to ´0´ (´1´) if acc_z ≥ 0 (acc_z < 0). Figure 9 shows the typical switching conditions between the four different orientations for the symmetrical mode (i.e. without hysteresis): portrait portraitupright upright landscape left portrait portraitupside upside down landscape landscaperight right portrait upright 2 1.5 1 0.5 0 0 45 90 135 180 225 270 315 360 -0.5 acc_y/acc_x -1 acc_x/sin(theta) -1.5 acc_y/sin(theta) -2 phi j Figure 9: Typical orientation switching conditions w/o hysteresis The orientation interrupt is enabled (disabled) by writing ´1´ (´0´) to bit (0x16) orient_en. The interrupt is generated if the value of (0x0C) orient has changed. It is automatically cleared after Rev. 1.15 Page 31 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet one stable period of the (0x0C) orient value. The interrupt status is stored in the (0x09) orient_int bit. If temporary or latched interrupt mode is used, after the generation of the interrupt the changed (0x0C) orient value is kept fixed as long as the interrupt persists (e. g. until the latch time expires or the interrupt is reset). After clearing the interrupt, the (0x0C) orient is only updated with the next following value change (i.e. with the next occurring interrupt). In order to ensure the continuous availability of up-to-date orientation data it is therefore optimal to use the nonlatched interrupt. It is strongly advised against using latched interrupt mode or temporary interrupt mode with latch times above 50 ms for orient recognition. 4.8.7.1 Orientation blocking The change of the (0x0C) orient value and – as a consequence – the generation of the interrupt can be blocked according to conditions selected by setting the value of the (0x2C) orient_blocking bits as described by table 21. Table 21: Blocking conditions for orientation recognition (0x2C) orient_blocking 00b 01b 10b 11b Conditions no blocking theta blocking theta blocking or acceleration slope in any axis > 0.2 g value of orient is not stable for at least 100 ms or theta blocking or acceleration slope in any axis > 0.4 g The theta blocking is defined by the following inequality: tan   blocking _ theta . 8 The parameter blocking_theta of the above given equation stands for the contents of the (0x2D) orient_theta bits. Hereby it is possible to define a blocking angle between 0° and 44.8°. The internal blocking algorithm saturates the acceleration values before further processing. As a consequence, the blocking angles are strictly valid only for a device at rest; they can be different if the device is moved. Example: To get a maximum blocking angle of 19° the parameter blocking_theta is determined in the following way: (8 * tan(19°) )² = 7.588, therefore, blocking_value = 8dec = 001000b has to be chosen. Rev. 1.15 Page 32 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet In order to avoid unwanted generation of the orientation interrupt in a nearly flat position (z ~ 0, sign change due to small movements or noise), a hysteresis of 0.2 g is implemented for the zaxis, i. e. a after a sign change the interrupt is only generated after |z| > 0.2 g. 4.8.8 Flat detection The flat detection feature gives information about the orientation of the devices´ z-axis relative to the g-vector, i. e. it recognizes whether the device is in a flat position or not. The condition for the device to be in the flat position is tan   parameter _ theta . 8 Like blocking_theta, used with orientation recognition, the parameter_theta stands for a userdefined setting. In this case the content of the (0x2E) flat_theta bits. The possible flat angles also range from 0° to 44.8°. To ensure proper operation, parameter_theta has to be less than or equal to blocking_theta. The flat interrupt is enabled (disabled) by writing ´1´ (´0´) to bit (0x16) flat_en. The flat interrupt is generated if the flat value has changed and the new value is stable for at least the time given by the (0x2F) flat_hold_time bits. The flat value is stored in the (0x0C) flat bit if the interrupt is enabled. This value is ´1´ if the device is in the flat position, it is ´0´ otherwise. The content of the (0x0C) flat bit is changed only if the interrupt is generated. The interrupt is automatically cleared after one sample period. Its status is stored in the (0x09) flat_int bit. If temporary or latched interrupt mode is used, after the generation of the interrupt the changed (0x0C) flat value is kept fixed as long as the interrupt persists (e. g. until the latch time expires or the interrupt is reset). After clearing the interrupt, the (0x0C) flat value is only updated with the next following value change (i.e. with the next occurring interrupt). The meaning of the (0x2F) flat_hold_time bits can be seen from table 22. Table 22: Meaning of flat_hold_time (0x2F) flat_hold_time 00b 01b 10b 11b Rev. 1.15 Time 0 512 ms 1024 ms 2048 ms Page 33 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 4.8.9 Low-g interrupt This interrupt is based on the comparison of acceleration data against a low-g threshold, which is most useful for free-fall detection. The interrupt is enabled (disabled) by writing ´1´ (´0´) to the (0x17) low_en bit. There are two modes available, „single‟ mode and „sum‟ mode. In „single‟ mode, the acceleration of each axis is compared with the threshold; in „sum‟ mode, the sum of absolute values of all accelerations |acc_x| + |acc_y| + |acc_z| is compared with the threshold. The mode is selected by the contents of the (0x24) low_mode bit: ´0´ means „single‟ mode, ´1´ means „sum‟ mode. The low-g threshold is set through the (0x23) low_th register. 1 LSB of (0x23) low_th always corresponds to an acceleration of 7.81 mg (i.e. increment is independent from g-range setting). A hysteresis can be selected by setting the (0x24) low_hy bits. 1 LSB of (0x24) low_hy always corresponds to an acceleration difference of 125 mg in any g-range (as well, increment is independent from g-range setting). The low-g interrupt is generated if the absolute values of the acceleration of all axes (´and´ relation, in case of single mode) or their sum (in case of sum mode) are lower than the threshold for at least the time defined by the (0x22) low_dur register. The interrupt is reset if the absolute value of the acceleration of at least one axis (´or´ relation, in case of single mode) or the sum of absolute values (in case of sum mode) is higher than the threshold plus the hysteresis for at least one data acquisition. In bit (0x09) low_int the interrupt status is stored. The relation between the content of (0x22) low_dur and the actual delay of the interrupt generation is: delay [ms] = [(0x22) low_dur + 1] • 2 ms. Therefore, possible delay times range from 2 ms to 512 ms. 4.8.10 High-g interrupt This interrupt is based on the comparison of acceleration data against a high-g threshold for the detection of shock or other high-acceleration events. The high-g interrupt is enabled (disabled) per axis by writing ´1´ (´0´) to bits (0x17) high_en_x, (0x17) high_en_y, and (0x17) high_en_z, respectively. The high-g threshold is set through the (0x26) high_th register. The meaning of an LSB of (0x26) high_th depends on the selected grange: it corresponds to 7.81 mg in 2g-range, 15.63 mg in 4g-range, 31.25 mg in 8g-range, and 62.5 mg in 16g-range (i.e. increment depends from g-range setting). A hysteresis can be selected by setting the (0x24) high_hy bits. Analogously to (0x26) high_th, the meaning of an LSB of (0x24) high_hy is g-range dependent: it corresponds to an acceleration difference of 125 mg in 2g-range, 250 mg in 4g-range, 500 mg in 8g-range, and 1000mg in 16g-range (as well, increment depends from g-range setting). The high-g interrupt is generated if the absolute value of the acceleration of at least one of the enabled axes (´or´ relation) is higher than the threshold for at least the time defined by the (0x25) high_dur register. The interrupt is reset if the absolute value of the acceleration of all enabled axes (´and´ relation) is lower than the threshold minus the hysteresis for at least the Rev. 1.15 Page 34 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec time defined by the (0x25) high_dur register. In bit (0x09) high_int the interrupt status is stored. The relation between the content of (0x25) high_dur and the actual delay of the interrupt generation is delay [ms] = [(0x22) low_dur + 1] • 2 ms. Therefore, possible delay times range from 2 ms to 512 ms. 4.8.10.1 Axis and sign information of high-g interrupt The axis which triggered the interrupt is indicated by bits (0x0C) high_first_x, (0x0C) high_first_y, and (0x0C) high_first_z. The bit corresponding to the triggering axis contains a ´1´ while the other bits hold a ´0´. These bits are cleared together with clearing the interrupt status. The sign of the triggering acceleration is stored in bit (0x0C) high_sign. If (0x0C) high_sign = ´0´ (´1´), the sign is positive (negative). 5. Register description 5.1 General remarks The entire communication with the device is performed by reading from and writing to registers (exception: dedicated mode, see chapter 4.2.2). Registers have a width of 8 bits; they are mapped to a common space of 64 addresses from (0x00) up to (0x3F). Within the used range there are several registers which are either completely or partially marked as „reserved‟. Any reserved bit is ignored when it is written and no specific value is guaranteed when read. It is recommended not to use registers at all which are completely marked as „reserved‟. Furthermore it is recommended to mask out (logical and with zero) reserved bits of registers which are partially marked as reserved. Registers with addresses from (0x00) up to (0x0E) are read-only. Any attempt to write to these registers is ignored. There are bits within some registers that connected with an action to be done and, therefore, are intended for write-only access, e. g. (0x21) reset_int or the entire (0x14) softreset register. Such bits always give ´0´ when read. Rev. 1.15 Page 35 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 5.2 Register map Register Address Default Value 0x3F 0x3E 0x3D 0x3C 0x3B 0x3A 0x39 0x38 0x37 0x36 0x35 0x34 0x33 0x32 0x31 0x30 0x2F 0x2E 0x2D 0x2C 0x2B 0x2A 0x29 0x28 0x27 0x26 0x25 0x24 0x23 0x22 0x21 0x20 0x1F 0x1E 0x1D 0x1C 0x1B 0x1A 0x19 0x18 0x17 0x16 0x15 0x14 0x13 0x12 0x11 0x10 0x0F 0x0E 0x0D 0x0C 0x0B 0x0A 0x09 0x08 0x07 0x06 0x05 0x04 0x03 0x02 0x01 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x10 0x00 0x00 0x04 0x70 0x01 0x00 0x10 0x08 0x08 0x18 0x0A 0x04 0x00 0x14 0x00 0xC0 0x0F 0x81 0x30 0x09 0x00 0x05 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x1F 0x03 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 n/a 0x03 bit7 bit6 bit5 bit4 offset_target_z cal_trigger reserved offset_reset bit3 bit2 reserved reserved offset_unfilt_z offset_unfilt_y offset_unfilt_x offset_filt_z offset_filt_y offset_filt_x offset_target_y cal_rdy reserved reserved reserved reserved nvm_load reserved bit1 bit0 offset_target_x hp_z_en hp_y_en i2c_wdt_en nvm_rdy self_test_sign cut_off hp_x_en i2c_wdt_sel spi3 nvm_prog_trig nvm_prog_mode self_test_axis reserved reserved reserved reserved reserved flat_hold_time reserved tap_samp tap_quiet tap_shock reserved flat_theta orient_theta orient_blocking tap_th orient_hyst reserved orient_mode tap_dur reserved reserved slope_th reserved slope_dur high_th high_dur reserved low_th low_dur high_hy reset_int low_mode reserved low_hy latch_int reserved int2_od int2_lvl int1_od int1_lvl reserved int_src_slope int_src_high int_src_low reserved int2_slope int2_high reserved int1_slope int1_high int2_low int1_data int1_low low_en reserved high_en_z slope_en_z high_en_y slope_en_y high_en_x slope_en_x reserved reserved int_src_data int_src_tap int2_orient int2_s_tap int2_d_tap int1_orient int1_s_tap int1_d_tap reserved orient_en s_tap_en data_en d_tap_en reserved reserved int2_flat int2_data int1_flat reserved reserved flat_en reserved softreset data_high_bw reserved shadow_dis reserved suspend lowpower_en reserved reserved reserved reserved sleep_dur bw range reserved reserved flat tap_sign data_int flat_int tap_first_z orient[2:0] tap_first_y orient_int s_tap_int acc_z_lsb acc_y_lsb acc_x_lsb high_sign slope_sign reserved d_tap_int reserved temp acc_z_msb 0 acc_y_msb 0 acc_x_msb 0 reserved Chip ID tap_first_x high_first_z slope_first_z high_first_y slope_first_y high_first_x slope_first_x slope_int high_int low_int new_data_z new_data_y new_data_x w/r write only read only reserved Rev. 1.15 Page 36 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 5.3 Chip ID Register (0x00) Chip ID contains the chip identification number. Table 23: Chip identification number, register (0x00) Bit 7 0 Bit 6 0 Bit 5 0 Bit 4 0 Bit 3 0 Bit 2 0 Bit 1 1 Bit 0 1 Register (0x01) is reserved 5.4 Acceleration data Register (0x02) contains the LSB part of x-axis acceleration data and the new data flag for the x-axis. Table 24: LSB part of x-axis acceleration, register (0x02) (0x02) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name acc_x_lsb acc_x_lsb new_data_x Description Bit 1 of x-axis acceleration data Bit 0 of x-axis acceleration data = x LSB (fixed to 0) (fixed to 0) (fixed to 0) (fixed to 0) (fixed to 0) New data flag of x-axis Register (0x03) contains the MSB part of x-axis acceleration data. Table 25: MSB part of x-axis acceleration, register (0x03) (0x03) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Rev. 1.15 Name acc_x_msb acc_x_msb acc_x_msb acc_x_msb acc_x_msb acc_x_msb acc_x_msb acc_x_msb Description Bit 9 of x-axis acceleration data = x MSB Bit 8 of x-axis acceleration data Bit 7 of x-axis acceleration data Bit 6 of x-axis acceleration data Bit 5 of x-axis acceleration data Bit 4 of x-axis acceleration data Bit 3 of x-axis acceleration data Bit 2 of x-axis acceleration data Page 37 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec Register (0x04) contains the LSB part of y-axis acceleration data and the new data flag for the y-axis. Table 26: LSB part of y-axis acceleration, register (0x04) (0x04) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name acc_y_lsb acc_y_lsb new_data_y Description Bit 1 of y-axis acceleration data Bit 0 of y-axis acceleration data = y LSB (fixed to 0) (fixed to 0) (fixed to 0) (fixed to 0) (fixed to 0) New data flag of y-axis Register (0x05) contains the MSB part of acceleration data for the y-axis. Table 27: MSB part of y-axis acceleration, register (0x05) (0x05) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name acc_y_msb acc_y_msb acc_y_msb acc_y_msb acc_y_msb acc_y_msb acc_y_msb acc_y_msb Description Bit 9 of y-axis acceleration data = y MSB Bit 8 of y-axis acceleration data Bit 7 of y-axis acceleration data Bit 6 of y-axis acceleration data Bit 5 of y-axis acceleration data Bit 4 of y-axis acceleration data Bit 3 of y-axis acceleration data Bit 2 of y-axis acceleration data Register (0x06) contains the LSB part of acceleration data and the new data flag for the z-axis. Table 28: LSB part of y-axis acceleration, register (0x06) (0x06) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Rev. 1.15 Name acc_z_lsb acc_z_lsb new_data_z Description Bit 1 of z-axis acceleration data Bit 0 of z-axis acceleration data = z LSB (fixed to 0) (fixed to 0) (fixed to 0) (fixed to 0) (fixed to 0) New data flag of z-axis Page 38 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Register (0x07) contains the MSB part of acceleration data for the z-axis. Table 29: MSB part of z-axis acceleration, register (0x07) (0x07) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name acc_z_msb acc_z_msb acc_z_msb acc_z_msb acc_z_msb acc_z_msb acc_z_msb acc_z_msb Description Bit 9 of z-axis acceleration data = z MSB Bit 8 of z-axis acceleration data Bit 7 of z-axis acceleration data Bit 6 of z-axis acceleration data Bit 5 of z-axis acceleration data Bit 4 of z-axis acceleration data Bit 3 of z-axis acceleration data Bit 2 of z-axis acceleration data 5.5 Temperature data Register (0x08) temp contains temperature data in two‟s complement representation. Center temperature = 24 °C  i.e. (0x08) temp = 00000000b 1 LSB increment of temperature sensor is 0.5 °C (0.9 °F). Table 30: Temperature data, register (0x08) Bit 7 Temp Bit 6 Temp Bit 5 Temp Bit 4 Temp Bit 3 Temp Bit 2 Temp Bit 1 Temp Bit 0 Temp 5.6 Status registers Register (0x09) contains the states of several interrupts. Table 31: Interrupt status, register (0x09) (0x09) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Rev. 1.15 Name flat_int orient_int s_tap_int d_tap_int - reserved slope_int high_int low_int Description Flat interrupt status Orientation interrupt status Single tap interrupt status Double tap interrupt status reserved Slope interrupt status High-g interrupt status Low-g interrupt status Page 39 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec Register (0x0A) contains the status of the new data interrupt. Table 32: New data status, register (0x0A) (0x0A) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name data_int - reserved - reserved - reserved - reserved - reserved - reserved - reserved - Description New data interrupt status reserved reserved reserved reserved reserved reserved reserved Register (0x0B) contains the sign and triggering axis information for the tap and slope interrupts. Here tap interrupt comprises both single and double tap interrupt. Table 33: Tap and slope interrupts status, register (0x0B) (0x0B) Bit Bit 7 Name tap_sign Bit 6 Bit 5 Bit 4 Bit 3 tap_first_z tap_first_y tap_first_x slope_sign Bit 2 Bit 1 Bit 0 slope_first_z slope_first_y slope_first_x Description st Sign of 1 tap that triggered the interrupt (´0´=positive, ´1´=negative) ´1´ indicates that z-axis is triggering axis of tap interrupt ´1´ indicates that y-axis is triggering axis of tap interrupt ´1´ indicates that x-axis is triggering axis of tap interrupt Sign of slope that triggered the interrupt (´0´=positive, ´1´=negative) ´1´ indicates that z-axis is triggering axis of slope interrupt ´1´ indicates that y-axis is triggering axis of slope interrupt ´1´ indicates that x-axis is triggering axis of slope interrupt Register (0x0C) contains the flat and orientation status, and the sign and triggering axis information for the high-g interrupt. Registers (0x0D) and (0x0E) are reserved. Table 34: Flat and orientation Status, register (0x0C) (0x0C) Bit Bit 7 Bit 6 Name flat orient Bit 5 Bit 4 orient orient Bit 3 high_sign Bit 2 Bit 1 Bit 0 high_first_z high_first_y high_first_x Description flat detection (´1´ if flat condition is fulfilled, ´0´ otherwise) orientation value of z-axis (´0´ if upward looking, ´1´ if downward looking) orientation value of x-y plane (´00´=portrait upright, ´01´=portrait upside-down, ´10´=landscape left, ´11´=landscape right) Sign of slope that triggered the interrupt (´0´=positive, ´1´=negative) ´1´ indicates that z-axis is triggering axis of high-g interrupt ´1´ indicates that y-axis is triggering axis of high-g interrupt ´1´ indicates that x-axis is triggering axis of high-g interrupt Registers (0x0D) and (0x0E) are reserved. Rev. 1.15 Page 40 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 5.7 g-range selection Register (0x0F) contains the selection of the g-range. Proper settings for (0x0F) range are ´0011b´ (selects ±2g range), ´0101b´ (selects ±4g range), ´1000b´ (selects ±8g range), ´1100b´ (selects ±16g range). All other settings are irregular; if such a setting is used, ±2g range is selected. Default value of (0x0F) range (after reset) is ´0011b´. Table 35: g-range, register (0x0F) Bit 7 reserved Bit 6 reserved Bit 5 reserved Bit 4 reserved Bit 3 range Bit 2 range Bit 1 range Bit 0 range 5.8 Bandwidths Register (0x10) contains the selection of the bandwidth for filtered acceleration data. Settings for (0x10) bw are ´00xxxb´ (bandwidth = 7.81 Hz), ´01000b´ (bandwidth = 7.81 Hz), ´01001b´ (bandwidth = 15.63 Hz), ´01010b´ (bandwidth = 31.25 Hz), ´01011b´ (bandwidth = 62.5 Hz), ´01100b´ (bandwidth = 125 Hz), ´01101b´ (bandwidth = 250 Hz), ´01110b´ (bandwidth = 500 Hz), ´01111b´ (bandwidth = 1000 Hz), ´1xxxxb´ (bandwidth = 1000 Hz). Default value of (0x10) bw (after reset) is ´11111b´. It is recommended to actively use the range from ´01000b´ to ´01111b´ only in order to be compatible with future products. Table 36: Bandwidths, register (0x10) Bit 7 reserved Bit 6 reserved Bit 5 reserved Bit 4 bw Bit 3 bw Bit 2 bw Bit 1 bw Bit 0 bw 5.9 Power modes Register (0x11) contains the configuration of the power modes. (0x11) suspend = ´1´ (´0´) sets (resets) suspend mode; default value of (0x11) suspend is ´0´. (0x11) lowpower_en = ´1´ (´0´) sets (resets) low-power mode, default value of (0x11) lowpower_en is ´0´. The settings for (0x11) sleep_dur are ´0000b´ to ´0101b´ (sleep phase duration = 0.5 ms), ´0110b´ (sleep phase duration = 1 ms), ´0111b´ (sleep phase duration = 2 ms), ´1000b´ (sleep phase duration = 4 ms), ´1001b´ (sleep phase duration = 6 ms), ´1010b´ (sleep phase duration = 10 ms), ´1011b´ (sleep phase duration = 25 ms), ´1100b´ (sleep phase duration = 50 ms), ´1101b´ (sleep phase duration = 100 ms), ´1110b´ (sleep phase duration = 500 ms), ´1111b´ (sleep phase duration = 1 s). Default value of (0x11) sleep_dur is ´0000b´. Table 37: Power modes, register (0x11) Bit 7 suspend Rev. 1.15 Bit 6 lowpower _en Bit 5 reserved Bit 4 sleep_ dur Bit 3 sleep_ dur Page 41 / not for publishing Bit 2 sleep_ dur Bit 1 sleep_ dur Bit 0 reserved 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 5.10 Special control settings Register (0x12) is reserved. Register (0x13) contains settings for the configuration of the acceleration data acquisition and the data output format. (0x13) data_high_bw = ´0´ (´1´) selects filtered (unfiltered) acceleration data to be written into the data registers (0x02) to (0x07). Default value of (0x13) data_high_bw is ´0´. (0x13) shadow_dis = ´0´ (´1´) enables (disables) the shadowing procedure. Shadowing means that the MSB register is updated by reading the corresponding LSB register. Default value of (0x13) shadow_dis is ´0´. Table 38: Acceleration data acquisition & data output format, register (0x13) Bit 7 data_high _bw Bit 6 shadow _dis Bit 5 reserved Bit 4 reserved Bit 3 reserved Bit 2 reserved Bit 1 reserved Bit 0 reserved Register (0x14) is the softreset register. A user-triggered reset (softreset) of the sensor is performed after writing ´0xB6´ to the softreset register. After that reset all registers return to their default values. Reading (0x14) softreset returns 0x00. Register (0x15) is reserved. 5.11 Interrupt settings Registers (0x16) and (0x17) contain the enable bits for the interrupts. Default value of each enable bit is ´0´. Table 39: Interrupt setting, register (0x16) (0x16) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Rev. 1.15 Name flat_en orient_en s_tap_en d_tap_en - reserved slope_en_z slope_en_y slope_en_x Description ´1´ (´0´) enables (disables) flat interrupt ´1´ (´0´) enables (disables) orientation interrupt ´1´ (´0´) enables (disables) single tap interrupt ´1´ (´0´) enables (disables) double tap interrupt reserved ´1´ (´0´) enables (disables) slope interrupt for z-axis ´1´ (´0´) enables (disables) slope interrupt for y-axis ´1´ (´0´) enables (disables) slope interrupt for x-axis Page 42 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec Table 40: Interrupt setting, register (0x17) (0x17) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name - reserved - reserved - reserved data_en low_en high_en_z high_en_y high_en_x Description reserved reserved reserved ´1´ (´0´) enables (disables) new data interrupt ´1´ (´0´) enables (disables) low-g interrupt ´1´ (´0´) enables (disables) high-g interrupt for z-axis ´1´ (´0´) enables (disables) high-g interrupt for y-axis ´1´ (´0´) enables (disables) high-g interrupt for x-axis Register (0x18) is reserved. Registers (0x19) to (0x1B) contain the mapping of interrupts onto the interrupt pins. Default value of each mapping bit is ´0´. Table 41: Interrupt mapping, register (0x19) (0x19) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name int1_flat int1_orient int1_s_tap int1_d_tap - reserved int1_slope int1_high int1_low Description ´1´ (´0´) maps (unmaps) flat interrupt to INT1 pin ´1´ (´0´) maps (unmaps) orientation interrupt to INT1 pin ´1´ (´0´) maps (unmaps) single tap interrupt to INT1 pin ´1´ (´0´) maps (unmaps) double tap interrupt to INT1 pin reserved ´1´ (´0´) maps (unmaps) slope interrupt to INT1 pin ´1´ (´0´) maps (unmaps) high-g interrupt to INT1 pin ´1´ (´0´) maps (unmaps) low-g interrupt to INT1 pin Table 42: Interrupt mapping, register (0x1A) (0x1A) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Rev. 1.15 Name int2_data - reserved - reserved - reserved - reserved - reserved - reserved int1_data Description ´1´ (´0´) maps (unmaps) new data interrupt to INT2 pin reserved reserved reserved reserved reserved reserved ´1´ (´0´) maps (unmaps) new data interrupt to INT1 pin Page 43 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec Table 43: Interrupt mapping, register (0x1B) (0x1B) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Name int2_flat int2_orient int2_s_tap int2_d_tap - reserved int2_slope int2_high int2_low Description ´1´ (´0´) maps (unmaps) flat interrupt to INT2 pin ´1´ (´0´) maps (unmaps) orientation interrupt to INT2 pin ´1´ (´0´) maps (unmaps) single tap interrupt to INT2 pin ´1´ (´0´) maps (unmaps) double tap interrupt to INT2 pin reserved ´1´ (´0´) maps (unmaps) slope interrupt to INT2 pin ´1´ (´0´) maps (unmaps) high-g interrupt to INT2 pin ´1´ (´0´) maps (unmaps) low-g interrupt to INT2 pin Registers (0x1C) and (0x1D) are reserved. Register (0x1E) contains the data source definition for those interrupts with selectable data source. Default value of each data source selection bit is ´0´. Table 44: Interrupt data source definition, register (0x1E) (0x1E) Bit Bit 7 Bit 6 Bit 5 Name - reserved - reserved int_src_data Bit 4 int_src_tap Bit 3 Bit 2 Bit 1 Bit 0 - reserved int_src_slope int_src_high int_src_low Description reserved reserved ´1´ (´0´) selects unfiltered (filtered) data for the new data interrupt ´1´ (´0´) selects unfiltered (filtered) data for the single tap and double tap interrupts reserved ´1´ (´0´) selects unfiltered (filtered) data for the slope interrupt ´1´ (´0´) selects unfiltered (filtered) data for the high-g interrupt ´1´ (´0´) selects unfiltered (filtered) data for the low-g interrupt Register (0x1F) is reserved. Register (0x20) contains the behavioural configuration (electrical behaviour) of the interrupt pins. Default value of (0x20) int1_od and (0x20) int2_od is ´0´. Default value of (0x20) int1_lvl and (0x20) int2_lvl is ´1´. Table 45: Electrical behaviour of interrupt pin, register (0x20) (0x20) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Rev. 1.15 Name - reserved - reserved - reserved - reserved int2_od int2_lvl int1_od int1_lvl Description reserved reserved reserved reserved ´0´ selects push-pull, ´1´ selects open drive for INT2 pin ´0´ (´1´) selects active level ´0´ (´1´) for INT2 pin ´0´ selects push-pull, ´1´ selects open drive for INT1 ´0´ (´1´) selects active level ´0´ (´1´) for INT1 pin Page 44 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Register (0x21) contains the interrupt reset bit and the interrupt mode selection. Writing ´1´ to (0x21) reset_int resets any latched interrupt. The settings for (0x21) latch_int are ´0000b´ (non-latched), ´0001b´ (temporary, 250 ms), ´0010b´ (temporary, 500 ms), ´0011b´ (temporary, 1 s), ´0100b´ (temporary, 2 s), ´0101b´ (temporary, 4 s), ´0110b´ (temporary, 8 s), ´0111b´ (latched), ´1000b´ (non-latched), ´1001b´ (temporary, 500 s), ´1010b´ (temporary, 500 s), ´1011b´ (temporary, 1 ms), ´1100b´ (temporary, 12.5 ms), ´1101b´ (temporary, 25 ms), ´1110b´ (temporary, 50 ms), ´1111b´ (latched). Default value of (0x21) latch_int is ´0000b´. Table 46: Interrupt reset bit and interrupt mode selection, register (0x21) Bit 7 reset_int Bit 6 reserved Bit 5 reserved Bit 4 reserved Bit 3 latch_ int Bit 2 latch_ int Bit 1 latch_ int Bit 0 latch_ int Register (0x22) contains the delay time definition for the low-g interrupt. The physical delay time can be computed from the content of (0x22) low_dur according to: delay [ms] = [(0x22) low_dur + 1] • 2 ms. Possible delay times range from 2 ms to 512 ms. Default value of (0x22) low_dur is 0x09, corresponding to a delay of 20 ms. Table 47: Delay time definition for the low-g interrupt, register (0x22) Bit 7 low_ dur Bit 6 low_ dur Bit 5 low_ dur Bit 4 low_ dur Bit 3 low_ dur Bit 2 low_ dur Bit 1 low_ dur Bit 0 low_ dur Register (0x23) contains the threshold definition for the low-g interrupt. An LSB of (0x23) low_th corresponds to an actual acceleration of 7.81 mg. Therefore, the threshold ranges from 0 g to 1.992 g. Default value of (0x23) low_th is 0x30, corresponding to an acceleration of 375 mg. Table 48: Threshold definition for the low-g interrupt, register (0x23) Bit 7 low_ th Bit 6 low_ th Bit 5 low_ th Bit 4 low_ th Bit 3 low_ th Bit 2 low_ th Bit 1 low_ th Bit 0 low_ th Register (0x24) contains the low-g interrupt mode selection, the low-g interrupt hysteresis setting, and the high-g interrupt hysteresis setting. Setting (0x24) low_mode to ´0´ (´1´) selects ´single´ mode (´sum´ mode). Default value is ´0´ (´single´ mode). Rev. 1.15 Page 45 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet (0x24) low_hy sets the hysteresis of the low-g interrupt. An LSB of (0x24) low_hy corresponds to an acceleration difference of 125 mg. Default value of (0x24) low_hy is ´01b´. (0x24) high_hy sets the hysteresis of the high-g interrupt. The meaning of an LSB of (0x24) high_hy depends on the selected g-range. It corresponds to an acceleration difference of 125 mg in 2g-range, 250 mg in 4g-range, 500 mg in 8g-range, and 1000mg in 16g-range. Default value of (0x24) high_hy is ´10b´. Table 49: Threshold definition for the low-g interrupt, register (0x24) Bit 7 high_ hy Bit 6 high_ hy Bit 5 reserved Bit 4 reserved Bit 3 reserved Bit 2 low_ mode Bit 1 low_ hy Bit 0 low_ hy Register (0x25) contains the delay time definition for the high-g interrupt. The physical delay time can be computed from the content of (0x25) high_dur according to delay [ms] = [(0x25) high_dur + 1] • 2 ms. Possible delay times range from 2 ms to 512 ms. Default value of (0x25) high_dur is 0x0F, corresponding to a delay of 32 ms. Table 50: Delay time definition for the high-g interrupt, register (0x25) Bit 7 high_ dur Bit 6 high_ dur Bit 5 high_ dur Bit 4 high_ dur Bit 3 high_ dur Bit 2 high_ dur Bit 1 high_ dur Bit 0 high_ dur Register (0x26) contains the threshold definition for the high-g interrupt. The meaning of an LSB of (0x26) high_th depends on the selected g-range. It corresponds to 7.81 mg in 2g-range, 15.63 mg in 4g-range, 31.25 mg in 8g-range, and 62.5 mg in 16g-range. Default value of (0x26) high_th is 0xC0. Table 51: Threshold definition for the high-g interrupt, register (0x26) Bit 7 high_ th Bit 6 high_ th Bit 5 high_ th Bit 4 high_ th Bit 3 high_ th Bit 2 high_ th Bit 1 high_ th Bit 0 high_ th Register (0x27) contains the definition of the number of samples to be evaluated for the slope interrupt (any-motion detection). The number of samples is N = (0x27) slope_dur + 1. Default value of (0x27) slope_dur is ´00b´. Table 52: Samples number definition for the slope interrupt, register (0x27) Bit 7 reserved Rev. 1.15 Bit 6 reserved Bit 5 reserved Bit 4 reserved Bit 3 reserved Page 46 / not for publishing Bit 2 reserved Bit 1 slope_ dur Bit 0 slope_ dur 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Register (0x28) contains the threshold definition for the slope interrupt. An LSB of (0x28) slope_th corresponds to an LSB of acceleration data. Its meaning therefore depends on the selected g-range. Default value of (0x28) slope_th is 0x14. Table 53: Slope threshold for the slope interrupt, register (0x28) Bit 7 slope_ th Bit 6 slope_ th Bit 5 slope_ th Bit 4 slope_ th Bit 3 slope_ th Bit 2 slope_ th Bit 1 slope_ th Bit 0 slope_ th Register (0x29) is reserved. Register (0x2A) contains the timing definitions for the single tap and double tap interrupts. (0x2A) tap_quiet = ´0´ (´1´) selects a quiet duration of 30 ms (20 ms). The default value of (0x2A) tap_quiet is ´0´. (0x2A) tap_shock = ´0´ (´1´) selects a shock duration of 50 ms (75 ms). The default value of (0x2A) tap_shock is ´0´. (0x2A) tap_dur selects the length of the time window for the second shock event (for double tap detection). The settings for (0x2A) tap_dur are ´000b´ (50 ms), ´001b´ (100 ms), ´010b´ (150 ms), ´011b´ (200 ms), ´100b´ (250 ms), ´101b´ (375 ms), ´110b´ (500 ms), ´111b´ (700 ms). The default value of (0x2A) tap_dur is ´100b´. Table 54: Tap Quiet duration and tap shock duration, register (0x2A) Bit 7 tap_ quiet Bit 6 tap_ shock Bit 5 reserved Bit 4 reserved Bit 3 reserved Bit 2 tap_ dur Bit 1 tap_ dur Bit 0 tap_ dur Register (0x2B) contains the definition of the number of samples to be processed after wakeup in low-power mode and the threshold definition for the single and double tap interrupts. (0x2B) tap_samp selects the number of samples that are processed after wake-up in the lowpower mode. The settings for (0x2B) tap_samp are ´00b´ (2 samples), ´01b´ (4 samples), ´10b´ (8 samples), and ´11b´ (16 samples). Default value of (0x2B) tap_samp is ´00b´. The meaning of an LSB of (0x2B) tap_th depends on the selected g-range. It corresponds to an acceleration difference of 62.5mg in 2g-range, 125mg in 4g-range, 250mg in 8g-range, and 500mg in 16g-range. Default value of (0x2B) tap_th is 0x0A. Table 55: Samples number after wake-up and threshold tap interrupt, register (0x2B) Bit 7 tap_ samp Rev. 1.15 Bit 6 tap_ samp Bit 5 reserved Bit 4 tap_ th Bit 3 tap_ th Bit 2 tap_ th Page 47 / not for publishing Bit 1 tap_ th Bit 0 tap_ th 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Register (0x2C) contains the definition of hysteresis, blocking, and mode for the orientation interrupt. (0x2C) orient_hyst sets the hysteresis of the orientation interrupt; 1 LSB always corresponds to 62.5 mg, in any g-range (i.e. increment is independent from g-range setting). Default value of (0x2C) orient_hyst is ´001b´. (0x2C) orient_blocking selects the kind of blocking that is used for the generation of the orientation interrupt. The settings for (0x2C) orient_blocking are ´00b´ (no blocking), ´01b´ (theta blocking), ´10b´ (theta blocking or slope in any axis > 0.2 g), and ´11b´ (orient value not stable for at least 100 ms or theta blocking or slope in any axis > 0.4 g). Default value of (0x2C) orient_blocking is ´10b´. (0x2C) orient_mode sets the thresholds for switching between the different orientations. The settings for (0x2C) orient_mode are ´00b´ (symmetrical), ´01b´ (high-asymmetrical), ´10b´ (lowasymmetrical), ´11b´ (symmetrical). Default value of (0x2C) orient_mode is ´00b´. Table 56: Hysteresis, Blocking for Orientation Interrupt, Register (0x2C) Bit 7 reserved Bit 6 orient_ hyst Bit 5 orient_ hyst Bit 4 orient_ hyst Bit 3 orient_ blocking Bit 2 orient_ blocking Bit 1 orient_ mode Bit 0 orient_ mode Register (0x2D) contains the definition of the theta blocking angle for the orientation interrupt. (0x2D) orient_theta defines a blocking angle between 0° and 44.8° as described in section “4.8.1.7 Orientation blocking”. Default value of (0x2D) orient_theta is 0x08. Table 57: Theta blocking angle, register (0x2D) Bit 7 reserved Bit 6 reserved Bit 5 orient_ theta Bit 4 orient_ theta Bit 3 orient_ theta Bit 2 orient_ theta Bit 1 orient_ theta Bit 0 orient_ theta Register (0x2E) contains the definition of the flat threshold angle for the flat interrupt. (0x2E) flat_theta defines a blocking angle between 0° and 44.8° as described in section”4.8.8 Flat detection”. Default value of (0x2E) flat_theta is 0x08. Table 58: Flat threshold angle, register (0x2E) Bit 7 reserved Bit 6 reserved Bit 5 flat_ theta Bit 4 flat_ theta Bit 3 flat_ theta Bit 2 flat_ theta Bit 1 flat_ theta Bit 0 flat_ theta Register (0x2F) contains the definition of the flat hold time. (0x2F) flat_hold_time defines the time a new flat value has to be at least stable for before the interrupt is generated. The settings for (0x2F) flat_hold_time are ´00b´ (0), ´01b´ (512 ms), ´10b´ (1024 ms), ´11b´ (2048 ms). Default value of (0x2F) flat_hold_time is ´01b´. Rev. 1.15 Page 48 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Table 59: Flat threshold angle, register (0x2F) Bit 7 reserved Bit 6 reserved Bit 5 flat_hold_ time Bit 4 flat_hold_ time Bit 3 reserved Bit 2 reserved Bit 1 reserved Bit 0 reserved Register (0x30) and (0x31) are reserved. 5.12 Self-test Register (0x32) contains the settings for the activation of the sensor self-test. (0x32) self_test_sign sets the sign of the electrostatic excitation. The settings for (0x32) self_test_sign are ´0´ (positive sign) and ´1´ (negative sign). Default value of (0x32) self_test_sign is ´0´. (0x32) self_test_axis defines the axis which shall be excited. Only one axis can be excited at the same time. The settings for (0x32) self_test_axis are ´00b´ (no self-test), ´01´ (x-axis), ´10´ (y-axis), and ´11´ (z-axis). Default value of (0x32) self_test_axis is ´00b´. Table 60: Sensor self-test, register (0x32) Bit 7 reserved Bit 6 reserved Bit 5 reserved Bit 4 reserved Bit 3 reserved Bit 2 self_test _sign Bit 1 self_test _axis Bit 0 self_test _axis 5.13 Non-volatile memory control (EEPROM control) Register (0x33) contains the control settings for the non-volatile memory (EEPROM). (0x33) nvm_load is used to perform a user-defined image update. Writing ´1´ (0x33) nvm_load starts the update procedure. The value ´1´ is kept as long as the update procedure runs, afterwards it is reset to ´0´. (0x33) nvm_rdy contains the status of writing the EEPROM. (0x33) nvm_rdy is ´0´ as long as writing the EEPROM endures, it is ´1´ if currently no write access is performed and, therefore, a new write access can be initiated. Writing ´1´to (0x33) nvm_prog_trig triggers writing the EEPROM. The EEPROM can only be written if it was unlocked before. Writing ´1´to (0x33) nvm_prog_mode unlocks the EEPROM. Rev. 1.15 Page 49 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Table 61: EEPROM control settings, register (0x33) Bit 7 reserved Bit 6 reserved Bit 5 reserved Bit 4 reserved Bit 3 nvm_load Bit 2 nvm_rdy Bit 1 nvm_prog _trig Bit 0 nvm_prog _mode 5.14 Interface configuration Register (0x34) contains the settings for the digital interfaces. Writing ´1´to (0x34) i2c_wdt_en enables the watchdog at the SDI pin (= SDA for I²C) if I²C is selected. Default value of (0x34) i2c_wdt_en is ´0´. (0x34) i2c_wdt_sel selects the I²C data pad watchdog timer period. The settings for (0x34) i2c_wdt_sel are ´0´ (1 ms) and ´1´ (50 ms). Default value of (0x34) i2c_wdt_sel is ´0´. (0x34) spi3 selects the SPI mode. The settings for (0x34) spi3 are ´0´ (4-wire SPI) and ´1´ (3wire SPI). Default value of (0x34) spi3 is ´0´. Table 62: EEPROM control settings, register (0x34) Bit 7 reserved Bit 6 reserved Bit 5 reserved Bit 4 reserved Bit 3 reserved Bit 2 i2c_wdt _en Bit 1 i2c_wdt _sel Bit 0 spi3 Register (0x35) is reserved. 5.15 Offset compensation Register (0x36) contains settings for the offset compensation in general, for fast offset compensation, and for slow offset compensation. Writing ´1´to (0x36) offset_reset sets all offset compensation registers (0x38 to 0x3D) to zero. Default value of (0x36) offset_reset is ´0´. (0x36) cal_trigger starts the fast compensation process for the specified axis. The settings for (0x36) cal_trigger are ´00b´ (no axis selected), ´01b´ (x-axis), ´10b´ (y-axis), ´11b´ (z-axis). A non-zero value is kept until the fast compensation procedure is finished. Default value of (0x36) cal_trigger is ´00b´. (0x36) cal_rdy indicates the state of the fast compensation. (0x36) cal_rdy is ´0´ when (0x36) cal_trigger has a nonzero value, otherwise (0x36) cal_rdy is ´1´. Writing ´1´ (´0´) to (0x36) hp_z_en enables (disables) slow offset compensation for the z-axis. Writing ´1´ (´0´) to (0x36) hp_y_en enables (disables) slow offset compensation for the y-axis. Rev. 1.15 Page 50 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Writing ´1´ (´0´) to (0x36) hp_x_en enables (disables) slow offset compensation for the x-axis. Default value for each of (0x36) hp_x_en, (0x36) hp_y_en, and (0x36) hp_x_en is ´0´, respectively. Table 63: Offset compensation, fast offset compensation, register (0x36) Bit 7 offset _reset Bit 6 cal_ trigger Bit 5 cal_ trigger Bit 4 cal_rdy Bit 3 reserved Bit 2 hp_z_en Bit 1 hp_y_en Bit 0 hp_x_en Register (0x37) contains settings for the offset compensation in general, and for slow offset compensation. (0x37) offset_target_z sets the target value for the offset compensation of the zaxis. (0x37) offset_target_y sets the target value for the offset compensation of the y-axis. (0x37) offset_target_x sets the target value for the offset compensation of the x-axis. The settings for (0x37) offset_target_x, (0x37) offset_target_y, and (0x37) offset_target_z are ´00b´ (0 g), ´01b´ (+1 g), ´10b´ (-1 g), and ´11b´ (0 g). Default value of each of (0x37) offset_target_x, (0x37) offset_target_y, and (0x37) offset_target_z is ´00b´, respectively. (0x37) cut_off defines the number of samples for comparison by the slow offset compensation. The settings for (0x37) cut_off are ´0´ (8 samples) and ´1´ (16 samples). The default value of (0x37) cut_off is ´0´. Table 64: Offset compensation, slow offset compensation, register (0x37) Bit 7 reserved Bit 6 offset_tar get_z Bit 5 offset_tar get_z Bit 4 offset_tar get_y Bit 3 offset_tar get_y Bit 2 offset_tar get_x Bit 1 offset_tar get_x Bit 0 cut_off Register (0x38) contains the compensation value for filtered data for the x-axis. The contents of each of the registers (0x38) to (0x3D) is added to the corresponding acceleration data; it can be set either automatically by one of the implemented compensation algorithms or manually. These registers are image registers of registers in the EEPROM; the content of the EEPROM is copied to them after every reset. Table 65: Filtered data compensation for the x-axis, register (0x38) Bit 7 offset_ filt_x Rev. 1.15 Bit 6 offset_ filt_x Bit 5 offset_ filt_x Bit 4 offset_ filt_x Bit 3 offset_ filt_x Page 51 / not for publishing Bit 2 offset_ filt_x Bit 1 offset_ filt_x Bit 0 offset_ filt_x 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Register (0x39) contains the compensation value for filtered data for the y-axis. Table 66: Filtered data compensation for the y-axis, register (0x39) Bit 7 offset_ filt_y Bit 6 offset_ filt_y Bit 5 offset_ filt_y Bit 4 offset_ filt_y Bit 3 offset_ filt_y Bit 2 offset_ filt_y Bit 1 offset_ filt_y Bit 0 offset_ filt_y Register (0x3A) contains the compensation value for filtered data for the z-axis. Table 67: Filtered data compensation for the z-axis, register (0x3A) Bit 7 offset_ filt_z Bit 6 offset_ filt_z Bit 5 offset_ filt_z Bit 4 offset_ filt_z Bit 3 offset_ filt_z Bit 2 offset_ filt_z Bit 1 offset_ filt_z Bit 0 offset_ filt_z Register (0x3B) contains the compensation value for unfiltered data for the x-axis. Table 68: Unfiltered data compensation for the x-axis, register (0x3B) Bit 7 offset_ unfilt_x Bit 6 offset_ unfilt_x Bit 5 offset_ unfilt_x Bit 4 offset_ unfilt_x Bit 3 offset_ unfilt_x Bit 2 offset_ unfilt_x Bit 1 offset_ unfilt_x Bit 0 offset_ unfilt_x Register (0x3C) contains the compensation value for unfiltered data for the y-axis. Table 69: Unfiltered data compensation for the x-axis, register (0x3C) Bit 7 offset_ unfilt_y Bit 6 offset_ unfilt_y Bit 5 offset_ unfilt_y Bit 4 offset_ unfilt_y Bit 3 offset_ unfilt_y Bit 2 offset_ unfilt_y Bit 1 offset_ unfilt_y Bit 0 offset_ unfilt_y Register (0x3D) contains the compensation value for unfiltered data for the z-axis. Table 70: Unfiltered data compensation for the y-axis, register (0x3D) Bit 7 offset_ unfilt_z Rev. 1.15 Bit 6 offset_ unfilt_z Bit 5 offset_ unfilt_z Bit 4 offset_ unfilt_z Bit 3 offset_ unfilt_z Page 52 / not for publishing Bit 2 offset_ unfilt_z Bit 1 offset_ unfilt_z Bit 0 offset_ unfilt_z 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec Registers (0x3E) and (0x3F) are image registers of registers in the EEPROM. They are not linked to any sensor-specific functionality. Rev. 1.15 Page 53 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 6. Digital interfaces The BMA250 supports two serial digital interface protocols for communication as a slave with a host device (when operating in general mode): SPI and I²C. The active interface is selected by the state of the Pin#11 (PS) „protocol select‟ pin: ´0´ (´1´) selects SPI (I²C). For details see section 4.2 Operational modes. By default, SPI operates in the standard 4-wire configuration. It can be re-configured by software to work in 3-wire mode instead of standard 4-wire mode. Both interfaces share the same pins. The mapping for each interface is given in the following table: Table 71: Mapping of the interface pins use w/ SPI use w/ I²C Pin# Name Description 1 SDO SDO address SPI: Data Output (4-wire mode) I²C: Used to set LSB of I²C address 2 SDx SDI SDA SPI: Data Input (4-wire mode) Data Input / Output (3-wire mode) I²C: Serial Data 10 CSB CSB unused Chip Select (enable) 12 SCx SCK SCL SPI: Serial Clock I²C: Serial Clock The following table shows the electrical specifications of the interface pins: Table 72: Electrical specification of the interface pins Parameter PS Impedance for Tri-state Detection Symbol Condition Min RTS Typ Max 1 Units M CTS 10 pF PS Impedance for Non-Tri-state RNTS 5 k Pull-up Resistance Rup Pull-down Resistance Input Capacitance I²C Bus Load Capacitance (max. drive capability) Rev. 1.15 Rdown Internal Pull-up Resistance to VDDIO Internal Pull-down Resistance to GND Cin CI2C_Load Page 54 / not for publishing 70 120 190 k 12 20 32 k 5 10 pF 400 pF 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 6.1 Serial peripheral interface (SPI) The timing specification for SPI of the BMA250 is given in the following table: Table 73: SPI timing Parameter Symbol Condition Min Clock Frequency fSPI Max. Load on SDI or SDO = 25pF SCK Low Pulse SCK High Pulse SDI Setup Time SDI Hold Time SDO Output Delay tSCKL tSCKH tSDI_setup tSDI_hold tSDO_OD CSB Setup Time CSB Hold Time tCSB_setup tCSB_hold Max Units 10 MHz 30 40 ns ns ns ns ns ns 20 20 20 20 Load = 25pF Load = 250pF, VDDIO = 2.4V 20 40 ns ns The following figure shows the definition of the SPI timings given in table 73: tCSB_setup tCSB_hold CSB SCK tSCKL tSCKH SDI SDO tSDI_setup tSDI_hold tSDO_OD Figure 10: SPI timing diagram The SPI interface of the BMA250 is compatible with two modes, ´00´ and ´11´. The automatic selection between [CPOL = ´0´ and CPHA = ´0´] and [CPOL = ´1´ and CPHA = ´1´] is done based on the value of SCK after a falling edge of CSB. Two configurations of the SPI interface are supported by the BMA250: 4-wire and 3-wire. The same protocol is used by both configurations. The device operates in 4-wire configuration by default. It can be switched to 3-wire configuration by writing ´1´ to (0x34) spi3. Pin SDI is used as the common data pin in 3-wire configuration. Rev. 1.15 Page 55 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet For single byte read as well as write operations, 16-bit protocols are used. The BMA250 also supports multiple-byte read operations. In SPI 4-wire configuration CSB (chip select low active), SCK (serial clock), SDI (serial data input), and SDO (serial data output) pins are used. The communication starts when the CSB is pulled low by the SPI master and stops when CSB is pulled high. SCK is also controlled by SPI master. SDI and SDO are driven at the falling edge of SCK and should be captured at the rising edge of SCK. The basic write operation waveform for 4-wire configuration is depicted in figure 11. During the entire write cycle SDO remains in high- impedance state. CSB SCK SDI R/W AD6 AD5 AD4 AD3 AD2 AD1 SDO AD0 DI7 DI6 DI5 DI4 DI3 DI2 DI1 DI0 Z tri-state Figure 11: 4-wire basic SPI write sequence (mode ´11´) The basic read operation waveform for 4-wire configuration is depicted in figure 12: CSB SCK SDI R/W AD6 AD5 AD4 AD3 AD2 AD1 AD0 SDO DO7 DO6 DO5 DO4 DO3 DO2 DO1 DO0 tri-state Figure 12: 4-wire basic SPI read sequence (mode ´11´) Rev. 1.15 Page 56 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet The data bits are used as follows: Bit0: Read/Write bit. When 0, the data SDI is written into the chip. When 1, the data SDO from the chip is read. Bit1-7: Address AD(6:0). Bit8-15: when in write mode, these are the data SDI, which will be written into the address. When in read mode, these are the data SDO, which are read from the address. Multiple read operations are possible by keeping CSB low and continuing the data transfer. Only the first register address has to be written. Addresses are automatically incremented after each read access as long as CSB stays active low. The principle of multiple read is shown in figure 13: Control byte Start RW CSB = 0 1 Register adress (02h) 0 0 0 0 0 1 0 X Data byte Data byte Data byte Data register - adress 02h Data register - adress 03h Data register - adress 04h X X X X X X X X X X X X X X X X X X X X X Stop X X CSB = 1 Figure 13: SPI multiple read In SPI 3-wire configuration CSB (chip select low active), SCK (serial clock), and SDI (serial data input and output) pins are used. The communication starts when the CSB is pulled low by the SPI master and stops when CSB is pulled high. SCK is also controlled by SPI master. SDI is driven (when used as input of the device) at the falling edge of SCK and should be captured (when used as the output of the device) at the rising edge of SCK. The protocol as such is the same in 3-wire configuration as it is in 4-wire configuration. The basic operation waveform (read or write access) for 3-wire configuration is depicted in figure 14: CSB SCK SDI RW AD6 AD5 AD4 AD3 AD2 AD1 AD0 DI7 DI6 DI5 DI4 DI3 DI2 DI1 DI0 Figure 14: 3-wire basic SPI read or write sequence (mode ´11´) Rev. 1.15 Page 57 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 6.2 Inter-Integrated Circuit (I²C) The I²C bus uses SCL (= SCx pin, serial clock) and SDA (= SDx pin, serial data input and output) signal lines. Both lines are connected to VDDIO externally via pull-up resistors so that they are pulled high when the bus is free. The I²C interface of the BMA250 is compatible with the I²C Specification UM10204 Rev. 03 (19 June 2007), available at http://www.nxp.com. The BMA250 supports I²C standard mode and fast mode, only 7-bit address mode is supported. For VDDIO = 1.2V to 1.8V the guaranteed voltage output levels are slightly relaxed as described in the Parameter Specification (table 1). The default I²C address of the device is 0011000b (0x18). It is used if the SDO pin is pulled to ´GND´. The alternative address 0011001b (0x19) is selected by pulling the SDO pin to ´VDDIO´. The timing specification for I²C of the BMA250 is given in table 74: Table 74: I²C timings Parameter Symbol Clock Frequency SCL Low Period SCL High Period SDA Setup Time SDA Hold Time Setup Time for a repeated Start Condition Hold Time for a Start Condition Setup Time for a Stop Condition Time before a new Transmission can start fSCL tLOW tHIGH tSUDAT tHDDAT tSUSTA 1.3 0.6 0.1 0.0 0.6 tHDSTA 0.6 tSUSTO 0.6 tBUF 1.3 Rev. 1.15 Condition Min Page 58 / not for publishing Max Units 400 kHz s 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Figure 15 shows the definition of the I²C timings given in table 74: SDA tBUF tf tLOW SCL tHIGH tHDSTA tr tHDDAT tSUDAT SDA tSUSTA tSUSTO Figure 15: I²C timing diagram The I²C protocol works as follows: START: Data transmission on the bus begins with a high to low transition on the SDA line while SCL is held high (start condition (S) indicated by I²C bus master). Once the START signal is transferred by the master, the bus is considered busy. STOP: Each data transfer should be terminated by a Stop signal (P) generated by master. The STOP condition is a low to HIGH transition on SDA line while SCL is held high. ACK: Each byte of data transferred must be acknowledged. It is indicated by an acknowledge bit sent by the receiver. The transmitter must release the SDA line (no pull down) during the acknowledge pulse while the receiver must then pull the SDA line low so that it remains stable low during the high period of the acknowledge clock cycle. In the following diagrams these abbreviations are used: S P ACKS ACKM NACKM RW Start Stop Acknowledge by slave Acknowledge by master Not acknowledge by master Read / Write A START immediately followed by a STOP (without SCK toggling from logic “1” to logic “0”) is not supported. If such a combination occurs, the STOP is not recognized by the device. Rev. 1.15 Page 59 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet I²C write access: I²C write access can be used to write a data byte in one sequence. The sequence begins with start condition generated by the master, followed by 7 bits slave address and a write bit (RW = 0). The slave sends an acknowledge bit (ACK = 0) and releases the bus. Then the master sends the one byte register address. The slave again acknowledges the transmission and waits for the 8 bits of data which shall be written to the specified register address. After the slave acknowledges the data byte, the master generates a stop signal and terminates the writing protocol. Example of an I²C write access: Control byte Slave Adress Start S 0 0 1 1 0 Register adress (0x10) RW ACKS 0 0 0 Data byte 0 0 0 1 0 0 Data (0x09) ACKS 0 0 X X X X X ACKS Stop X X X P Figure 16: I²C write I²C read access: I²C read access also can be used to read one or multiple data bytes in one sequence. A read sequence consists of a one-byte I²C write phase followed by the I²C read phase. The two parts of the transmission must be separated by a repeated start condition (Sr). The I²C write phase addresses the slave and sends the register address to be read. After slave acknowledges the transmission, the master generates again a start condition and sends the slave address together with a read bit (RW = 1). Then the master releases the bus and waits for the data bytes to be read out from slave. After each data byte the master has to generate an acknowledge bit (ACK = 0) to enable further data transfer. A NACKM (ACK = 1) from the master stops the data being transferred from the slave. The slave releases the bus so that the master can generate a STOP condition and terminate the transmission. The register address is automatically incremented and, therefore, more than one byte can be sequentially read out. Once a new data read transmission starts, the start address will be set to the register address specified in the latest I²C write command. By default the start address is set at 0x00. In this way repetitive multi-bytes reads from the same starting address are possible. In order to prevent the I²C slave of the device to lock-up the I²C bus, a watchdog timer (WDT) is implemented. The WDT observes internal I²C signals and resets the I²C interface if the bus is locked-up by the BMA250. The activity and the timer period of the WDT can be configured through the bits (0x34) i2c_wdt_en and (0x34) i2c_wdt_sel. Writing ´1´ (´0´) to (0x34) i2c_wdt_en activates (de-activates) the WDT. Writing ´0´ (´1´) to (0x34) i2c_wdt_se selects a timer period of 1 ms (50 ms). Rev. 1.15 Page 60 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet Example of an I²C read access: S 0 0 1 1 0 RW ACKS 0 0 0 dummy Control byte Slave Adress Start X Register adress (0x02) 0 0 0 0 0 1 ACKS Stop P 0 Data byte Slave Adress Start Sr 0 0 1 1 0 Read Data (0x02) RW ACKS 0 0 1 Data byte X X X X X X Read Data (0x03) ACKM X X X X X Data byte … X X X X X X X X X X X X X X X X X X Data byte Data byte Read Data (0x07) X X … X Read Data (0x05) ACKM Read Data (0x06) X X Data byte Read Data (0x04) … X ACKM X ACKM X X X X X X X X ACKM X … X NACK X X Stop P Figure 17: I²C multiple read Rev. 1.15 Page 61 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 7. Pin-out and connection diagram 7.1 Pin-out Top View Pads not visible! Bottom View Pads visible! Figure 18: Pin-out top view Figure 19 Pin-out bottom view Table 75: Pin description Pin# Name I/O Type 1 SDO Digital out 2 SDx Digital I/O 3 VDDIO Supply 4 5 6 7 NC INT1 INT2 VDD -Digital out Digital out Supply 8 9 10 11 GNDIO GND CSB PS Ground Ground Digital in Digital in 12 SCx Digital in Rev. 1.15 Description Serial data output in SPI Address select in I²C mode see chapter 6.2 SDA serial data I/O in I²C SDI serial data input in SPI 4W SDA serial data I/O in SPI 3W Digital I/O supply voltage (1.2V … 3.6V) Interrupt output 1 Interrupt output 2 Power supply for analog & digital domain (1.62V … 3.6V) Ground for I/O Ground for digital & analog Chip select for SPI mode Protocol select (GND = SPI, VDDIO = I²C, float = µC-less). Pin must not float unless dedicated mode is used, see chapter 4.2.2 SCK for SPI serial clock SCL for I²C serial clock in SPI 4W Connect to In SPI 3W in I²C SDO DNC (float) GND for default addr. SDI SDA SDA VDDIO VDDIO VDDIO GND INT1 INT2 VDD GND INT1 INT2 VDD GND INT1 INT2 VDD GND GND CSB GND GND GND CSB GND GND GND DNC (float) VDDIO SCK SCK SCL Page 62 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 7.2 Connection diagram 4-wire SPI Figure 20: 4-wire SPI connection Rev. 1.15 Page 63 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 7.3 Connection diagram 3-wire SPI Figure 21: 3-wire SPI connection Rev. 1.15 Page 64 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 7.4 Connection diagram I2C Figure 22: I²C connection Note: the recommended value for C1, C2 is 100 nF. Rev. 1.15 Page 65 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 8. Package 8.1 Outline dimensions The sensor housing is a standard LGA package. It is compliant with JEDEC Standard MO-229 Type VGGD-3. Its dimensions are the following. Figure 23: Package outline dimensions Rev. 1.15 Page 66 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Bosch Sensortec Data sheet 8.2 Sensing axes orientation If the sensor is accelerated in the indicated directions, the corresponding channel will deliver a positive acceleration signal (dynamic acceleration). If the sensor is at rest and the force of gravity is acting along the indicated directions, the output of the corresponding channel will be negative (static acceleration). Example: If the sensor is at rest or at uniform motion in a gravity field according to the figure given below, the output signals are: • • • ± 0g for the X channel ± 0g for the Y channel + 1g for the Z channel Figure 24: Orientation of sensing axis The following table lists all corresponding output signals on X, Y, and Z while the sensor is at rest or at uniform motion in a gravity field under assumption of a ±2g range setting and a top down gravity vector as shown above. Table 76: Output signals depending on sensor orientation upright upright Sensor Orientation (gravity vector ) Output Signal X 0g / 0LSB 1g / 256LSB 0g / 0LSB -1g / -256LSB 0g / 0LSB 0g / 0LSB Output Signal Y -1g / -256LSB 0g / 0LSB +1g / 256LSB 0g / 0LSB 0g / 0LSB 0g / 0LSB Output Signal Z 0g / 0LSB 0g / 0LSB 0g / 0LSB 0g / 0LSB 1g / 256LSB -1g / -256LSB Rev. 1.15 Page 67 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 8.3 Landing pattern recommendation For the design of the landing patterns, we recommend the following dimensioning: Figure 25: Landing patterns relative to the device pins, dimensions are in mm Rev. 1.15 Page 68 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 8.4 Marking 8.4.1 Mass production samples Table 77: Marking of mass production samples Labeling CCC TL Name Symbol Remark Lot counter CCC 3 alphanumeric digits, variable to generate mass production trace-code Product number T 1 alphanumeric digit, fixed to identify product type, T = “8” Sub-con ID L 1 alphanumeric digit, variable to identify sub-con (L = “A” or L = “U” or L = “P”) Pin 1 identifier • -- Name Symbol Remark Eng. sample ID N 1 alphanumeric digit, fixed to identify engineering sample, N = “e” Sample ID XX 2 alphanumeric digits, variable to generate trace-code Counter ID CC 2 alphanumeric digits, variable to generate trace-code Pin 1 identifier • -- 8.4.2 Engineering samples Table 78: Marking of engineering samples Labeling XXN CC Rev. 1.15 Page 69 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 8.5 Soldering guidelines The moisture sensitivity level of the BMA250 sensors corresponds to JEDEC Level 1, see also - IPC/JEDEC J-STD-020C "Joint Industry Standard: Moisture/Reflow Classification for non-hermetic Solid State Surface Mount Devices" Sensitivity - IPC/JEDEC J-STD-033A "Joint Industry Standard: Handling, Packing, Shipping and Use of Moisture/Reflow Sensitive Surface Mount Devices". The sensor fulfils the lead-free soldering requirements of the above-mentioned IPC/JEDEC standard, i.e. reflow soldering with a peak temperature up to 260°C. Figure 26: Soldering profile Rev. 1.15 Page 70 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 8.6 Handling instructions Micromechanical sensors are designed to sense acceleration with high accuracy even at low amplitudes and contain highly sensitive structures inside the sensor element. The MEMS sensor can tolerate mechanical shocks up to several thousand g's. However, these limits might be exceeded in conditions with extreme shock loads such as e.g. hammer blow on or next to the sensor, dropping of the sensor onto hard surfaces etc. We recommend to avoid g-forces beyond the specified limits during transport, handling and mounting of the sensors in a defined and qualified installation process. This device has built-in protections against high electrostatic discharges or electric fields (e.g. 2kV HBM); however, anti-static precautions should be taken as for any other CMOS component. Unless otherwise specified, proper operation can only occur when all terminal voltages are kept within the supply voltage range. Unused inputs must always be tied to a defined logic voltage level. 8.7 Tape and reel specification The BMA250 is shipped in a standard cardboard box. The box dimension for 1 reel is: L x W x H = 35cm x 35cm x 6cm BMA250 quantity: 10,000pcs per reel, please handle with care. Figure 27: Tape and reel dimensions in mm Rev. 1.15 Page 71 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 8.7.1 Orientation within the reel  Processing direction  Figure 28: Orientation of the BMA250 devices relative to the tape 8.8 Environmental safety The BMA250 sensor meets the requirements of the EC restriction of hazardous substances (RoHS) directive, see also: Directive 2002/95/EC of the European Parliament and of the Council of 27 January 2003 on the restriction of the use of certain hazardous substances in electrical and electronic equipment. 8.8.1 Halogen content Results of chemical analysis indicate that the BMA250 contains less than 900ppm (by weight) of Fluorine, Chlorine, Iodine and Bromine (i.e. < 50ppm per each substance). Therefore the BMA250 can be regarded as halogen-free. For more details on the analysis results please contact your Bosch Sensortec representative. 8.8.2 Internal package structure Within the scope of Bosch Sensortec‟s ambition to improve its products and secure the mass product supply, Bosch Sensortec qualifies additional sources (e.g. 2nd source) for the LGA package of the BMA250. While Bosch Sensortec took care that all of the technical packages parameters are described above are 100% identical for all sources, there can be differences in the chemical content and the internal structural between the different package sources. However, as secured by the extensive product qualification process of Bosch Sensortec, this has no impact to the usage or to the quality of the BMA250 product. Rev. 1.15 Page 72 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 9. Legal disclaimer 9.1 Engineering samples Engineering Samples are marked with “e”. Samples may vary from the valid technical specifications of the product series contained in this data sheet. They are therefore not intended or fit for resale to third parties or for use in end products. Their sole purpose is internal client testing. The testing of an engineering sample may in no way replace the testing of a product series. Bosch Sensortec assumes no liability for the use of engineering samples. The Purchaser shall indemnify Bosch Sensortec from all claims arising from the use of engineering samples. 9.2 Product use Bosch Sensortec products are developed for the consumer goods industry. They may only be used within the parameters of this product data sheet. They are not fit for use in life-sustaining or security sensitive systems. Security sensitive systems are those for which a malfunction is expected to lead to bodily harm or significant property damage. In addition, they are not fit for use in products which interact with motor vehicle systems. The resale and/or use of products are at the purchaser‟s own risk and his own responsibility. The examination of fitness for the intended use is the sole responsibility of the Purchaser. The purchaser shall indemnify Bosch Sensortec from all third party claims arising from any product use not covered by the parameters of this product data sheet or not approved by Bosch Sensortec and reimburse Bosch Sensortec for all costs in connection with such claims. The purchaser must monitor the market for the purchased products, particularly with regard to product safety, and inform Bosch Sensortec without delay of all security relevant incidents. 9.3 Application examples and hints With respect to any examples or hints given herein, any typical values stated herein and/or any information regarding the application of the device, Bosch Sensortec hereby disclaims any and all warranties and liabilities of any kind, including without limitation warranties of noninfringement of intellectual property rights or copyrights of any third party. The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics. They are provided for illustrative purposes only and no evaluation regarding infringement of intellectual property rights or copyrights or regarding functionality, performance or error has been made. Rev. 1.15 Page 73 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. BMA250 Data sheet Bosch Sensortec 10. Document history and modification Revision 0.8 0.9 1.0 1.05 1.10 1.15 Chapter 1 4.2.2 4.3 4.4.1 4.8.3 5.11 5.11 5.2 4.8.7 6.2 Description of modification/changes Date Document release Update table 1 Added missing table numbers Update table 7 Update range register 0x0F Document rev. 1.0 update / no changes Typo correction, int1_od, int2_od Typo correction, register 0x25 Typo correction in table 53 description Typo correction register map Update orientation interrupt Update I2C address selection 17 December 2010 26 January 2011 03 March 2011 17 June 2011 02 November 2011 31 May 2012 Bosch Sensortec GmbH Gerhard-Kindler-Strasse 8 72770 Reutlingen / Germany contact@bosch-sensortec.com www.bosch-sensortec.com Modifications reserved | Printed in Germany Specifications subject to change without notice Document number: BST-BMA250-DS002-05 Version_1.15_052012 Rev. 1.15 Page 74 / not for publishing 31 - May - 2012 © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Bosch: BMA250 0330.SB0.121