MMA8653FCR1

Freescale Semiconductor Data Sheet: Technical Data Document Number: MMA8653FC Rev. 2.2, 03/2015 An Energy-Efficient Solution by Freescale MMA8653FC 3-Axis, 10-bit Digital MMA8653FC Accelerometer The MMA8653FC is an intelligent, low-power, three-axis, capacitive micromachined accelerometer with 10 bits of resolution. This accelerometer is packed with embedded functions with flexible user-programmable options, configurable to two interrupt pins. Embedded interrupt functions enable overall power savings, by relieving the host processor from continuously polling data. There is access to either low-pass or high-pass filtered data, which minimizes the data analysis required for jolt detection and faster transitions. The device can be configured to generate inertial wake-up interrupt signals from any combination of the configurable embedded functions, enabling the MMA8653FC to monitor inertial events while remaining in a low-power mode during periods of inactivity. The MMA8653FC is available in a small 10-pin DFN package (2 mm x 2 mm x 1 mm). Top and Bottom View Features • • • • • • • • • • 1.95 V to 3.6 V supply voltage 1.62 V to 3.6 V digital interface voltage ±2 g, ±4 g, and ±8 g dynamically selectable full-scale ranges Output Data Rates (ODR) from 1.56 Hz to 800 Hz 10-bit digital output I2C digital output interface with programmable interrupts One embedded channel of configurable motion detection (Freefall) Orientation (Portrait/Landscape) detection with fixed hysteresis of 15°. Configurable automatic ODR change triggered by the Auto-Wake/Sleep state change Self-Test Typical applications • • • • • • • • 10-pin DFN 2 mm x 2 mm x 1 mm Case 98ASA00301D Top View 10 SDA VDD 1 SCL 2 9 GND INT1 3 8 VDDIO BYP 4 7 GND INT2 5 6 GND Tilt compensation in e-compass applications Pin Connections Static orientation detection (Portrait/Landscape, Up/Down, Left/Right, Back/ Front position identification) Notebook, tablet, e-reader, and laptop tumble and freefall detection Real-time orientation detection (virtual reality and gaming 3D user orientation feedback) Real-time activity analysis (pedometer step counting, freefall drop detection for HDD, dead-reckoning GPS backup) Motion detection for portable product power saving (Auto-SLEEP and Auto-WAKE for cell phone, PDA, GPS, gaming) Shock and vibration monitoring (mechatronic compensation, shipping and warranty usage logging) User interface (tilt menu scrolling) ORDERING INFORMATION Part Number Temperature Range Package Description Shipping MMA8653FCR1 -40°C to +85°C DFN-10 Tape and Reel Freescale reserves the right to change the detail specifications as may be required to permit improvements in the design of its products. © 2013–2015 Freescale Semiconductor, Inc. All rights reserved. Table 1. Feature comparison of the MMA865xFC devices Feature ADC Resolution (bits) MMA8652FC MMA8653FC 12 10 Digital Sensitivity in 2 g mode (counts/g) 1024 256 Low-Power Mode Yes Yes Auto-WAKE Yes Yes Auto-SLEEP Yes Yes 32-Level FIFO Yes No Low-Pass Filter Yes Yes High-Pass Filter Yes No Transient Detection with High-Pass Filter Yes No Fixed Orientation Detection No Yes Programmable Orientation Detection Yes No Data-Ready Interrupt Yes Yes Single-Tap Interrupt Yes No Double-Tap Interrupt Yes No Directional Tap Interrupt Yes No Freefall Interrupt Yes Yes Motion Interrupt with Direction Yes No MMA8653FC 2 Sensors Freescale Semiconductor, Inc. Contents 1 Block Diagram and Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 Pin descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.3 Typical application circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Mechanical and Electrical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.1 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.2 Mechanical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2.3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.4 I2C interface characteristic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3 Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.1 Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.2 Zero-g offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.3 Self-Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5 Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.1 Device calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.2 8-bit or 10-bit data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.3 Low power modes vs. high resolution modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 5.4 Auto-WAKE/SLEEP mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 5.5 Freefall detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5.6 Orientation detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5.7 Interrupt register configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 5.8 Serial I2C interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 6 Register Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 6.1 Register address map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 6.2 Register bit map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 6.3 Data registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.4 System status and ID registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 6.5 Data configuration registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 6.6 Portrait/Landscape configuration and status registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 6.7 Freefall/Motion configuration and status registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 6.8 Auto-WAKE/SLEEP detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 6.9 System and control registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 6.10 Data calibration registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 7 Mounting Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 7.1 Overview of soldering considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 7.2 Halogen content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 7.3 PCB mounting/soldering recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 8 Tape and Reel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 8.1 Tape dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 8.2 Device orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 9 Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 10 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Related Documentation The MMA8653FC device features and operations are described in a variety of reference manuals, user guides, and application notes. To find the most-current versions of these documents: 1. Go to the Freescale homepage at: http://www.freescale.com/ 2. 3. In the Keyword search box at the top of the page, enter the device number MMA8653FC. In the Refine Your Result pane on the left, click on the Documentation link. Sensors Freescale Semiconductor, Inc. MMA8653FC 3 MMA8653FC 4 Sensors Freescale Semiconductor, Inc. 1 Block Diagram and Pin Descriptions 1.1 Block diagram BYP VDD VDDIO Voltage Regulator Clock GEN Internal OSC INT1 INT2 GND Y-axis Transducer MUX X-axis Transducer C-to-V Converter Gain AAF Embedded Functions ADC I2 C Interface SDA SCL Anti-Aliasing Filter Z-axis Transducer Orientation Detection with hysteresis and Z-lockout Freefall Detection Auto-WAKE/Auto-SLEEP configurable with debounce counter and multiple motion interrupts for control MODE Options Low Power Low Noise + Power High Resolution Normal ACTIVE Mode WAKE ACTIVE Mode Auto-WAKE/SLEEP SLEEP MODE Options Low Power Low Noise + Power High Resolution Normal Figure 1. MMA8653 block diagram MMA8653FC Sensors Freescale Semiconductor, Inc. 5 1.2 Pin descriptions SDA 10 1 VDD GND SCL VDDIO INT1 GND BYP GND 6 5 INT2 Figure 2. Pin connections (bottom view) Table 1. Pin descriptions Pin # Pin Name 1 VDD 2 Description Notes Power supply Device power is supplied through the VDD line. Power supply decoupling capacitors should be placed as close as possible to pin 1 and pin 8 of the device. SCL(1) I2C Serial Clock 7-bit I2C device address is 0x1D. 3 INT1 Interrupt 1 output The interrupt source and pin settings are user-programmable through the I2C interface. 4 BYP Internal regulator output capacitor connection 5 INT2 Interrupt 2 output 6 GND Ground 7 GND Ground 8 VDDIO 9 GND 10 SDA(1) See INT1. Digital Interface Power supply Ground I2C Serial Data See SCL. 1. The control signals SCL and SDA are not tolerant of voltages higher than VDDIO + 0.3 V. If VDDIO is removed, then the control signals SCL and SDA will clamp any logic signals with their internal ESD protection diodes. The SDA and SCL I2C connections are open drain, and therefore require a pullup resistor to VDDIO. 1.3 Typical application circuit Top View VDD 1 F 0.1 F VDDIO 1 k 1 10 2 9 3 8 4 7 5 6 SDA VDDIO 1 k SCL BYP INT1 VDDIO 0.1 F 0.1 F INT2 Note: 4.7 k Pullup resistors on INT1/INT2 can be added for open-drain operation. Figure 3. Typical application circuit MMA8653FC 6 Sensors Freescale Semiconductor, Inc. 2 Mechanical and Electrical Specifications 2.1 Absolute maximum ratings Stresses above those listed as “absolute maximum ratings” may cause permanent damage to the device. Exposure to maximum rating conditions for extended periods may affect device reliability. Table 2. Maximum ratings Rating Symbol Value Unit Maximum acceleration (all axes, 100 s) gmax 10,000 g Supply voltage VDD –0.3 to +3.6 V Vin –0.3 to VDDIO + 0.3 V Ddrop 1.8 m Input voltage on any control pin (SCL, SDA) Drop test Operating temperature range TOP –40 to +85 °C Storage temperature range TSTG –40 to +125 °C Symbol Value Unit HBM ±2000 V Table 3. ESD and latch-up protection characteristics Rating Human body model Machine model Charge device model Latch-up current at T = 85°C MM ±200 V CDM ±500 V ILU ±100 mA This device is sensitive to mechanical shock. Improper handling can cause permanent damage to the part. This part is ESD-sensitive. Improper handling can cause permanent damage to the part. MMA8653FC Sensors Freescale Semiconductor, Inc. 7 2.2 Mechanical characteristics Table 4. Mechanical characteristics at VDD = 2.5 V, VDDIO = 1.8 V, TA = 25°C, unless otherwise noted Parameter Full-Scale measurement range Sensitivity Symbol FS So Test Conditions Min Typ Max Unit FS[1:0] set to 00 ±2 g mode ±2 FS[1:0] set to 01 ±4 g mode ±4 FS[1:0] set to 10 ±8 g mode ±8 FS[1:0] set to 00 ±2 g mode 256 FS[1:0] set to 01 ±4 g mode 128 FS[1:0] set to 10 ±8 g mode 64 ±2.5 % –40°C to 85°C 0.0074 %/°C g LSB/g Sensitivity accuracy Soa Sensitivity change vs. temperature TCS Zero-g level offset accuracy (1) TyOff 25 mg TyOffPBM 33.5 mg –40°C to 85°C 0.27 mg/°C x +22.5 y +26 z +195.5 Zero-g level offset accuracy, post-board mount (2) Zero-g level change vs. temperature TCO Self-Test output change (±2 g mode) STOC ODR accuracy ODRa Output data bandwidth Output noise Operating temperature range 3.1 BW RMS LSB ODR/3 Normal mode ODR = 400 Hz TAGOC % ODR/2 182 –40 Hz µg/Hz 85 °C 1. Before board mount. 2. Post-board mount offset specifications are based on an 8-layer PCB, relative to 25°C. MMA8653FC 8 Sensors Freescale Semiconductor, Inc. 2.3 Electrical characteristics Table 5. Electrical characteristics at VDD = 2.5 V, VDDIO = 1.8 V, T = 25°C, unless otherwise noted Parameter Supply voltage Interface supply voltage Low Power mode Normal mode Boot-Up current Value of capacitor on BYP pin Symbol Test Conditions VDD VDDIO IddLP Idd Min Typ Max Unit 1.95 2.5 3.6 V 1.62 1.8 3.6 V ODR = 1.563 Hz 6.5 ODR = 6.25 Hz 6.5 ODR = 12.5 Hz 6.5 ODR = 50 Hz 15 ODR = 100 Hz 26 ODR = 200 Hz 49 ODR = 400 Hz 94 ODR = 800 Hz 184 ODR = 1.563 Hz 27 ODR = 6.25 Hz 27 ODR = 12.5 Hz 27 ODR = 50 Hz 27 ODR = 100 Hz 49 ODR = 200 Hz 94 ODR = 400 Hz 184 ODR = 800 Hz 184 IddBoot VDD = 2.5 V, the current during the Boot sequence is integrated over 0.5 ms, using a recommended bypass cap A A 1 Cap –40°C to 85°C IddStby 25°C Digital high-level input voltage SCL, SDA VIH VDD = 3.6 V, VDDIO = 3.6 V Digital low-level input voltage SCL, SDA VIL VDD = 1.95 V, VDDIO = 1.62 V High-level output voltage INT1, INT2 VOH VDD = 3.6 V, VDDIO = 3.6 V, IO = 500 A Low-level output voltage INT1, INT2 VOL VDD = 1.95 V, VDDIO = 1.62 V, IO = 500 A 0.1*VDDIO Low-level output voltage SDA VOLS IO = 3 mA 0.4 Output source current INT1, INT2 Isource Voltage high level VOUT = 0.9 x VDDIO 2 mA Output sink current INT1, INT2 Isink Voltage high level VOUT = 0.9 x VDDIO 3 mA Power-on ramp time Tpr Standby current 75 mA 100 470 nF 1.4 5 A V 0.7*VDDIO 0.3*VDDIO 0.9*VDDIO V V 0.001 V V 1000 ms 500 µs Tbt Time from VDDIO on and VDD > VDD min until I2C is ready for operation, Cbyp = 100 nf Turn-on time Ton1 Time to obtain valid data from Standby mode to Active mode 2/ODR + 1 ms - Turn-on time Ton2 Time to obtain valid data from valid voltage applied 2/ODR + 2 ms - 85 °C Boot time Operating temperature range TAGOC 350 –40 MMA8653FC Sensors Freescale Semiconductor, Inc. 9 2.4 I2C interface characteristic Table 6. I2C slave timing values (1) Parameter Symbol I2C Fast Mode Min Max 400 Unit SCL clock frequency fSCL 0 Bus-free time between STOP and START condition tBUF 1.3 s (Repeated) START hold time tHD;STA 0.6 s Repeated START setup time tSU;STA 0.6 s STOP condition setup time tSU;STO 0.6 kHz s s SDA data hold time tHD;DAT 0.05 SDA setup time tSU;DAT 100 ns SCL clock low time tLOW 1.3 s SCL clock high time tHIGH 0.6 SDA and SCL rise time tr SDA and SCL fall time SDA valid time tf (4) SDA valid acknowledge time tSP Capacitive load for each bus line Cb 1. 2. 3. 4. 5. 20 + 0.1 Cb 300 ns 20 + 0.1 Cb (3) 300 ns tVD;ACK Pulse width of spikes on SDA and SCL that must be suppressed by internal input filter s (3) tVD;DAT (5) 0.9 (2) 0 0.9 (2) s 0.9 (2) s 50 ns 400 pF All values referred to VIH(min) (0.3 VDD) and VIL(max) (0.7 VDD) levels. This device does not stretch the LOW period (tLOW) of the SCL signal. Cb = total capacitance of one bus line in pF. tVD;DAT = time for data signal from SCL LOW to SDA output (HIGH or LOW, depending on which one is worse). tVD;ACK = time for Acknowledgement signal from SCL LOW to SDA output (HIGH or LOW, depending on which one is worse). VIL = 0.3 VDD VIH = 0.7 VDD Figure 4. I2C slave timing diagram MMA8653FC 10 Sensors Freescale Semiconductor, Inc. 3 Terminology 3.1 Sensitivity The sensitivity is represented in counts/g. • In ±2 g mode, sensitivity = 256 counts/g. • In ±4 g mode, sensitivity = 128 counts/g. • In ±8 g mode, sensitivity = 64 counts/g. 3.2 Zero-g offset Zero-g Offset (TyOff) describes the deviation of an actual output signal from the ideal output signal if the sensor is stationary. A sensor stationary on a horizontal surface will measure 0 g in X-axis and 0 g in Y-axis, whereas the Z-axis will measure 1 g. The output is ideally in the middle of the dynamic range of the sensor (content of OUT Registers 0x00, data expressed as a 2's complement number). A deviation from ideal value in this case is called Zero-g offset. Offset is to some extent a result of stress on the MEMS sensor, and therefore the offset can slightly change after mounting the sensor onto a printed circuit board or after exposing it to extensive mechanical stress. 3.3 Self-Test Self-Test can be used to verify the transducer and signal chain functionality without the need to apply external mechanical stimulus. When Self-Test is activated: • An electrostatic actuation force is applied to the sensor, simulating a small acceleration. In this case, the sensor outputs will exhibit a change in their DC levels which, are related to the selected full scale through the device sensitivity. • The device output level is given by the algebraic sum of the signals produced by the acceleration acting on the sensor and by the electrostatic test-force. MMA8653FC Sensors Freescale Semiconductor, Inc. 11 4 Modes of Operation ACTIVE SLEEP OFF STANDBY WAKE Figure 5. Operating modes for MMA8653FC Table 7. Operating modes Mode OFF I2C Bus State Powered down VDD VDDIO Description VDD • The device is powered off. • All analog and digital blocks are shutdown. • I2C bus inhibited. STANDBY I2C communication with MMA8653FC is possible ON VDDIO = High VDD = High ACTIVE bit is cleared • Only digital blocks are enabled. • Analog subsystem is disabled. • Internal clocks disabled. ACTIVE (WAKE/SLEEP) I2C communication with MMA8653FC is possible ON VDDIO = High VDD = High ACTIVE bit is set All blocks are enabled (digital, analog). Some registers are reset when transitioning from STANDBY to ACTIVE. These registers are all noted in the device memory map register table. The SLEEP and WAKE modes are ACTIVE modes. For more information about how to use the SLEEP and WAKE modes and how to transition between these modes, see Section 5. MMA8653FC 12 Sensors Freescale Semiconductor, Inc. 5 Functionality The MMA8653FC is a low-power, digital output 3-axis linear accelerometer with a I2C interface with embedded logic used to detect events and notify an external microprocessor over interrupt lines. • 8-bit or 10-bit data • Four different oversampling options that allow for the optimum resolution vs. current consumption trade-off to be made for a given application • Low-power and auto-WAKE/SLEEP modes for reducing current consumption • Freefall detection (one channel) • Single default angle for portrait landscape detection algorithm, for addressing screen orientation • Two independent interrupt output pins that are programmable among four interrupt sources (Data Ready, Freefall, Orientation, Auto-WAKE) All functionality is available in ±2 g, ±4 g or ±8 g dynamic measurement ranges. There are many configuration settings for enabling all of the different functions. Separate application notes are available to help configure the device for each embedded functionality. 5.1 Device calibration The device is factory calibrated for sensitivity and Zero-g offset for each axis. The trim values are stored in Non-Volatile Memory (NVM). On power-up, the trim parameters are read from NVM and applied to the circuitry. In normal use, further calibration in the end application is not necessary. However, the MMA8653FC allows you to adjust the offset for each axis after power-up, by changing the default offset values. The user offset adjustments are stored in three volatile 8-bit registers (OFF_X, OFF_Y, OFF_Z). 5.2 8-bit or 10-bit data The measured acceleration data is stored in the following registers as 2’s complement 10-bit numbers: • OUT_X_MSB, OUT_X_LSB • OUT_Y_MSB, OUT_Y_LSB • OUT_Z_MSB, OUT_Z_LSB The most significant eight bits of each axis are stored in OUT_X (Y, Z)_MSB, so applications needing only 8-bit results can use these three registers (and ignore the OUT_X/Y/Z_LSB registers). To use only 8-bit results, the F_READ bit in CTRL_REG1 must be set. When the F_READ bit is cleared, the fast read mode is disabled. • When the full-scale is set to ±2 g, the measurement range is –2 g to +1.996 g, and each count corresponds to (1/256) g (3.8 mg) at 10-bit resolution. • When the full-scale is set to ±4 g, the measurement range is –4 g to +3.992 g, and each count corresponds to (1/128) g • (7.8 mg) at 10-bit resolution. • When the full-scale is set to ±8 g, the measurement range is –8 g to +7.984 g, and each count corresponds to (1/64) g (15.6 mg) at 10-bit resolution. • If only the 8-bit results are used, then the resolution is reduced by a factor of 16. For more information about the data manipulation between data formats and modes, see application note AN4083, Data Manipulation and Basic Settings for Xtrinsic MMA865xFC Accelerometers. There is a device driver available that can be used with the Sensor Toolbox demo board (LFSTBEB865xFC) with this application note. Table 8. Accelerometer 10-bit output data 10-bit Data Range ±2 g (3.9 mg/LSB) Range ±4 g (7.8 mg/LSB) Range ±8 g (15.6 mg/LSB) 01 1111 1111 1.996 g +3.992 g +7.984 g 01 1111 1110 1.992 g +3.984 g +7.968 g … … … … 00 0000 0001 0.003 g +0.007 g +0.015 g 00 0000 0000 0.000 g 0.000 g 0.000 g 11 1111 1111 –0.003 g –0.007 g –0.015 g … … … … 10 0000 0001 –1.961 g –3.992 g –7.984 g MMA8653FC Sensors Freescale Semiconductor, Inc. 13 Table 8. Accelerometer 10-bit output data (Continued) 10-bit Data Range ±2 g (3.9 mg/LSB) Range ±4 g (7.8 mg/LSB) Range ±8 g (15.6 mg/LSB) 10 0000 0000 –2.000 g –4.000 g –8.000 g 8-bit Data Range ±2 g (15.6 mg) Range ±4 g (31.25 mg) Range ±8 g (62.5 mg) 0111 1111 1.984 g +3.968 g +7.937 g 0111 1110 1.968 g +3.937 g +7.875 g … … … … 0000 0001 +0.015 g +0.031 g +0.062 g 0000 0000 0.000 g 0.000 g 0.000 g 1111 1111 –0.015 g –0.031 g –0.062 g … … … … 1000 0001 –1.984 g –3.968 g –7.937 g 1000 0000 –2.000 g –4.000 g –8.000 g Range ±4 g (31.25 mg/LSB) Range ±8 g (62.5 mg/LSB) Table 9. Accelerometer 8-bit output data 8-bit Data 5.3 Range ±2 g (15.6 mg/LSB) 0111 1111 1.9844 g +3.9688 g +7.9375 g 0111 1110 1.9688 g +3.9375 g +7.8750 g … … … … 0000 0001 +0.0156 g +0.0313 g +0.0625 g 0000 0000 0.000 g 0.0000 g 0.0000 g 1111 1111 –0.0156 g –0.0313 g –0.0625 g … … … … 1000 0001 –1.9844 g –3.9688 g –7.9375 g 1000 0000 –2.0000 g –4.0000 g –8.0000 g Low power modes vs. high resolution modes The MMA8653FC can be optimized for lower power modes or for higher resolution of the output data. One of the oversampling schemes of the data can be activated when MODS = 10 in Register 0x2B, which will improve the resolution of the output data only. The highest resolution is achieved at 1.56 Hz. There is a trade-off between low power and high resolution. Low power can be achieved when the oversampling rate is reduced. When MODS = 11, the lowest power is achieved. The lowest power is achieved when the sample rate is set to 1.56 Hz. 5.4 Auto-WAKE/SLEEP mode The MMA8653FC can be configured to transition between sample rates (with their respective current consumption) based on four of the interrupt functions of the device. The advantage of using the Auto-WAKE/SLEEP is that the system can automatically transition to a higher sample rate (higher current consumption) when needed, but spends the majority of the time in the SLEEP mode (lower current) when the device does not require higher sampling rates. • Auto-WAKE refers to the device being triggered by one of the interrupt functions to transition to a higher sample rate. This may also interrupt the processor to transition from a SLEEP mode to a higher power mode. • SLEEP mode occurs after the accelerometer has not detected an interrupt for longer than the user-definable timeout period. The device will transition to the specified lower sample rate. It may also alert the processor to go into a lower power mode, to save on current during this period of inactivity. The Interrupts that can WAKE the device from SLEEP are Orientation detection and Freefall detection. The interrupts that can keep the device from falling asleep are the same interrupts that can wake the device. MMA8653FC 14 Sensors Freescale Semiconductor, Inc. 5.5 Freefall detection MMA8653FC has an interrupt architecture for detecting a Freefall. • Freefall can be enabled. • Freefall is detected when the acceleration magnitude is less than the configured threshold. The freefall configuration does not use a high-pass filter. The detection of “Freefall” involves the monitoring of the X, Y, and Z axes for the condition where the acceleration magnitude is below a user-specified threshold for a user-definable amount of time. Usable threshold levels are typically between ±100 mg and ±500 mg. 5.6 Orientation detection The MMA8653FC incorporates an advanced orientation detection algorithm with the ability to detect all six orientations shown in Figure 6. The algorithm uses a single default trip point setting. The transition from portrait to landscape is fixed at 45° midpoint angle and ±15° hysteresis angle. This allows for smooth transitions from portrait to landscape at approximately 30° and landscape to portrait at approximately 60° (Figure 7). Top View Side View PORTRAIT UP BACK Pin 1 Earth Gravity LANDSCAPE LEFT Xout @ 0 g Yout @ –1 g Zout @ 0 g Xout @ 0 g Yout @ 0 g Zout @ –1 g LANDSCAPE RIGHT FRONT Xout @ 0 g Yout @ 0 g Zout @ 1 g Xout @ –1 g Yout @ 0 g Zout @ 0 g PORTRAIT DOWN Xout @ 1 g Yout @ 0 g Zout @ 0 g Z Pin 1 X Xout @ 0 g Yout @ 1 g Zout @ 0 g Y (Top View) Direction of the Detectable Accelerations Figure 6. Sensitive axes orientation MMA8653FC Sensors Freescale Semiconductor, Inc. 15 PORTRAIT 90° PORTRAIT 90° Landscape-to-Portrait Trip Angle = 60° Portrait-to-Landscape Trip Angle = 30° 0° Landscape 0° Landscape Figure 7. Landscape-to-Portrait transition trip angles Based on the known functionality of linear accelerometers, when a device is oriented at a certain angle from flat and the device is rotating at slow angular speeds about the Z-axis, it is not possible to detect changes in acceleration. The angle at which the device no longer detects the orientation change is referred to as the “Z-lockout angle” (Figure 8). The MMA8653FC orientation detection algorithm is configured to operate when the device is oriented at an angle of 29° or greater from flat (Zout = –1 g or Zout = 1 g), with an accuracy of ±2°. . When lifting the device upright from the flat position, orientation detection will be active for orientation angles greater than 29° from flat. This is the only setting available. UPRIGHT 90° NORMAL DETECTION REGION Z-LOCK LOCKOUT REGION 0° FLAT Figure 8. Z-Tilt angle lockout transition MMA8653FC 16 Sensors Freescale Semiconductor, Inc. 5.7 Interrupt register configurations There are four configurable interrupts in the MMA8653FC: Data Ready, Motion/Freefall, Orientation, and Auto-SLEEP events. Configurable interrupts These four interrupt sources can be routed to one of two interrupt pins. The interrupt source must be enabled and configured. If the event flag is asserted because the event condition is detected, then the corresponding interrupt pin (INT1 or INT2) will assert. Data Ready Motion/Freefall INT1 Interrupt Controller Orientation INT2 Auto-SLEEP 7 INT ENABLE 7 INT CFG Figure 9. System interrupt generation • The MMA8653FC features an interrupt signal that indicates when a new set of measured acceleration data is available, thus simplifying data synchronization in the digital system that uses the device. • The MMA8653FC may also be configured to generate other interrupt signals accordingly, to the programmable embedded functions of the device for Motion, Freefall, and Orientation. Serial I2C interface 5.8 Acceleration data may be accessed through an I2C interface, thus making the device particularly suitable for direct interfacing to a microcontroller. The acceleration data and configuration registers embedded inside the MMA8653FC are accessed through the I2C serial interface (Table 10). • To enable the I2C interface, VDDIO line must be tied high (to the interface supply voltage). If VDD is not present and VDDIO is present, then the MMA8653FC is in OFF mode—and communications on the I2C interface are ignored. • The I2C interface may be used for communications between other I2C devices; the MMA8653FC does not affect the I2C bus. Table 10. Serial Interface pins Pin Name Pin Description 2C Serial Clock SCL I SDA I2C Serial Data Notes There are two signals associated with the I2C bus; the Serial Clock Line (SCL) and the Serial Data line (SDA). • SDA is a bidirectional line used for sending and receiving the data to/from the interface. • External pullup resistors connected to VDDIO are expected for SDA and SCL. When the bus is free, both SCL and SDA lines are high. The I2C interface is compliant with Fast mode (400 kHz), and Normal mode (100 kHz) I2C standards (Table 11). I2C operation: 1. 2. 3. The transaction on the bus is started through a start condition (START) signal. A START condition is defined as a high-tolow transition on the data line while the SCL line is held high. After START has been transmitted by the Master, the bus is considered busy. The next byte of data transmitted after START contains the slave address in the first seven bits. The eighth bit tells whether the Master is receiving data from the slave or is transmitting data to the slave. After a start condition and when an address is sent, each device in the system compares the first seven bits with its address. If the device’s address matches the sent address, then the device considers itself addressed by the Master. MMA8653FC Sensors Freescale Semiconductor, Inc. 17 4. 5. 6. The 9th clock pulse following the slave address byte (and each subsequent byte) is the acknowledge (ACK). The transmitter must release the SDA line during the ACK period. The receiver must then pull the data line low, so that it remains stable low during the high period of the acknowledge clock period. A Master may also issue a repeated START during a data transfer. The MMA8653FC expects repeated STARTs to be used to randomly read from specific registers. A low-to-high transition on the SDA line while the SCL line is high is defined as a stop condition (STOP). A data transfer is always terminated by a STOP. The MMA8653FC's standard slave address is 0011101 or 0x01D. Table 11. I2C Device address sequence 5.8.1 1. 2. 3. 4. 5. Master Command [6:0] Device address [6:0] Device address R/W 8-bit final value Read 0011101 0x1D 1 0x3B Write 0011101 0x1D 0 0x3A Single-byte read The transmission of an 8-bit command begins on the falling edge of SCL. After the eight clock cycles are used to send the command, note that the data returned is sent with the MSB first after the data is received. Figure 10 shows the timing diagram for the accelerometer 8-bit I2C read operation. The Master (or MCU) transmits a start condition (ST) to the MMA8653FC [slave address (0x1D), with the R/W bit set to “0” for a write], and the MMA8653FC sends an acknowledgement. Next the Master (or MCU) transmits the address of the register to read, and the MMA8653FC sends an acknowledgement. The Master (or MCU) transmits a repeated start condition (SR) and then addresses the MMA8653FC (0x1D), with the R/W bit set to “1” for a read from the previously selected register. The Slave then acknowledges and transmits the data from the requested register. The Master does not acknowledge (NAK) the transmitted data, but transmits a stop condition to end the data transfer. ST Device Address[7:1] Register Address[7:0] W AK Slave SR Device Address[7:1] R AK NAK SP AK Data[7:0] Figure 10. Single-Byte Read timing (I2C) NOTE For the following subsections, use the following legend. Legend ST: Start Condition SP: Stop Condition NAK: No Acknowledge SR: Repeated Start Condition AK: Acknowledge R: Read = 1 5.8.2 W: Write = 0 Multiple byte read (See Table 11 for next auto-increment address.) 1. 2. 3. 4. When performing a multi-byte read or “burst read”, the MMA8653FC automatically increments the received register address commands after a read command is received. After following the steps of a single byte read, multiple bytes of data can be read from sequential registers after each MMA8653FC acknowledgment (AK) is received, Until a no acknowledge (NAK) occurs from the Master, Followed by a stop condition (SP), which signals the end of transmission. MMA8653FC 18 Sensors Freescale Semiconductor, Inc. Master ST Device Address[7:1] W AK Slave AK Master Slave Register Address[7:0] Data[7:0] SR Device Address[7:1] R AK AK Data[7:0] AK AK Data[7:0] NAK SP Data[7:0] Figure 11. Multiple Byte Read timing (I2C) 5.8.3 1. 2. 3. 4. Master Single byte write To start a write command, the Master transmits a start condition (ST) to the MMA8653FC, slave address ($1D) with the R/W bit set to “0” for a write, The MMA8653FC sends an acknowledgement. Next the Master (MCU) transmits the address of the register to write to, and the MMA8653FC sends an acknowledgement. Then the Master (or MCU) transmits the 8-bit data to write to the designated register, and the MMA8653FC sends an acknowledgement that it has received the data. Because this transmission is complete, the Master transmits a stop condition (SP) to the data transfer. The data sent to the MMA8653FC is now stored in the appropriate register. ST Device Address[7:1] W Register Address[7:0] AK Slave Data[7:0] AK SP AK Figure 12. Single Byte Write timing (I2C) 5.8.4 Multiple byte write (See Table 11 for next auto-increment address.) 1. 2. Master After a write command is received, the MMA8653FC automatically increments the received register address commands. Therefore, after following the steps of a single byte write, multiple bytes of data can be written to sequential registers after each MMA8653FC acknowledgment (ACK) is received. ST Device Address[7:1] Slave W Register Address[7:0] AK Data[7:0] AK Data[7:0] AK SP AK Figure 13. Multiple Byte Write timing (I2C) MMA8653FC Sensors Freescale Semiconductor, Inc. 19 6 Register Descriptions 6.1 Register address map Table 12. MMA8653FC register address map Field STATUS(1),(2) (1) OUT_X_MSB (1) OUT_X_LSB (1) Auto-Increment Address Register Address F_READ = 0 F_READ = 1 R 0x00 0x01 R 0x01 0x02 0x03 Output — [7:0] are 8 MSBs of 10-bit sample. R 0x02 0x03 0x00 Output — [7:6] are 2 LSBs of 10-bit real-time sample Type Default 00000000 Hex Value Comment 0x00 Real time status OUT_Y_MSB R 0x03 0x04 0x05 Output — [7:0] are 8 MSBs of 10-bit real-time sample OUT_Y_LSB(1) R 0x04 0x05 0x00 Output — [7:6] are 2 LSBs of 10-bit real-time sample OUT_Z_MSB(1) R 0x05 0x06 0x00 Output — [7:0] are 8 MSBs of 10-bit real-time sample R 0x06 Output — [7:6] are 2 LSBs of 10-bit real-time sample Reserved R 0x07–0x0A — 00000000 0x00 Reserved. Read return 0x00. SYSMOD R 0x0B 0x0C 00000000 0x00 Current System Mode R 0x0C 0x0D 00000000 0x00 Interrupt status R 0x0D 0x0E 01001010 0x5A Device ID (0x5A) R/W 0x0E 0x0F 00000000 0x00 Dynamic Range Settings R 0x0F — 00000000 0x00 Reserved. Read return 0x00. R 0x10 0x11 00000000 0x00 Landscape/Portrait orientation status R/W 0x11 0x12 10000000 0x80 Landscape/Portrait configuration. (1) OUT_Z_LSB (1),(2) INT_SOURCE (3) WHO_AM_I (3),(4) XYZ_DATA_CFG Reserved (1),(2) PL_STATUS (3),(4) PL_CFG (3),(4) 0x00 R/W 0x12 0x13 00000000 0x00 Landscape/Portrait debounce counter PL_BF_ZCOMP(3) R 0x13 0x14 01000100 0x44 Back/Front, Z-Lock Trip threshold PL_THS_REG(3) R 0x14 0x15 10000100 0x84 Portrait to Landscape Trip angle FF_MT_CFG(3),(4) R/W 0x15 0x16 00000000 0x00 FF_MT_SRC(1),(2) R 0x16 0x17 00000000 0x00 Freefall/Motion event source register R/W 0x17 0x18 00000000 0x00 Freefall/Motion threshold register R/W 0x18 0x19 00000000 0x00 Freefall/Motion debounce counter R 0x19–0x28 — 00000000 0x00 Reserved. Read return 0x00. PL_COUNT (3),(4) FF_MT_THS (3),(4) FF_MT_COUNT Reserved (3),(4) Freefall/Motion functional block configuration R/W 0x29 0x2A 00000000 0x00 Counter setting for Auto-SLEEP/WAKE (3),(4) R/W 0x2A 0x2B 00000000 0x00 Data Rates, ACTIVE Mode. (3),(4) CTRL_REG2 R/W 0x2B 0x2C 00000000 0x00 Sleep Enable, OS Modes, RST, ST CTRL_REG3(3),(4) R/W 0x2C 0x2D 00000000 0x00 Wake from Sleep, IPOL, PP_OD (3),(4) R/W 0x2D 0x2E 00000000 0x00 Interrupt enable register (3),(4) 0x2F 00000000 0x00 Interrupt pin (INT1/INT2) map ASLP_COUNT CTRL_REG1 CTRL_REG4 R/W 0x2E (3),(4) OFF_X R/W 0x2F 0x30 00000000 0x00 X-axis offset adjust OFF_Y(3),(4) R/W 0x30 0x31 00000000 0x00 Y-axis offset adjust OFF_Z(3),(4) R/W 0x31 0x0D 00000000 0x00 Z-axis offset adjust CTRL_REG5 1. 2. 3. 4. The register data is only valid in ACTIVE mode. Register contents are reset when transition from STANDBY to ACTIVE mode occurs. Register contents are preserved when transition from ACTIVE to STANDBY mode occurs. Modification of this register’s content can only occur when device is in STANDBY mode, except CTRL_REG1 ACTIVE bit and CTRL_REG2 RST bit. MMA8653FC 20 Sensors Freescale Semiconductor, Inc. 6.2 Register bit map Table 13. MMA8653FC register bit map Reg Field Definition Type Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 00 STATUS Data Status R ZYXOW ZOW YOW XOW ZYXDR ZDR YDR XDR 01 OUT_X_MSB 10-bit X Data R XD9 XD8 XD7 XD6 XD5 XD4 XD3 XD2 02 OUT_X_LSB 10-bit X Data R XD1 XD0 0 0 0 0 0 0 03 OUT_Y_MSB 10-bit Y Data R YD9 YD8 YD7 YD6 YD5 YD4 YD3 YD2 04 OUT_Y_LSB 10-bit Y Data R YD1 YD0 0 0 0 0 0 0 05 OUT_Z_MSB 10-bit Z Data R ZD9 ZD8 ZD7 ZD6 ZD5 ZD4 ZD3 ZD2 06 OUT_Z_LSB 10-bit Z Data R ZD1 ZD0 0 0 0 0 0 0 07–0A Reserved — R 0 0 0 0 0 0 0 0 0B SYSMOD System Mode R 0 0 0 0 0 0 SYSMOD1 SYSMOD0 0C INT_SOURCE Interrupt Status R SRC_ASLP 0 0 SRC_LNDPRT 0 SRC_FF_MT 0 SRC_DRDY 0D WHO_AM_I ID Register R 0 1 0 1 1 0 1 0 0E XYZ_DATA_CFG Data Config R/W 0 0 0 0 0 0 FS1 FS0 0F Reserved — R — — — — — — — — 10 PL_STATUS Portrait Landscape Status R NEWLP LO 0 0 0 LAPO[1] LAPO[0] BAFRO 11 PL_CFG Portrait Landscape Configuration R/W DBCNTM PL_EN 0 0 0 0 0 0 12 PL_COUNT Portrait Landscape Debounce R/W DBNCE[7] DBNCE[6] DBNCE[5] DBNCE[4] DBNCE[3] DBNCE[2] DBNCE[1] DBNCE[0] PL_BF_ZCOMP Portrait Landscape Back/Front Z Comp R 0 1 0 0 0 1 0 0 13 14 PL_THS_REG Portrait Landscape Threshold R 1 0 0 0 0 1 0 0 15 FF_MT_CFG Freefall/Motion Config R/W ELE OAE ZEFE YEFE XEFE 0 0 0 16 FF_MT_SRC Freefall/Motion Status R EA 0 ZHE ZHP YHE YHP XHE XHP 17 FF_MT_THS Freefall/Motion Threshold R/W DBCNTM THS6 THS5 THS4 THS3 THS2 THS1 THS0 18 FF_MT_COUNT Freefall/Motion Debounce R/W D7 D6 D5 D4 D3 D2 D1 D0 Reserved — R — — — — — — — — 29 ASLP_Count Counter setting for Auto-SLEEP/WAKE R/W D7 D6 D5 D4 D3 D2 D1 D0 2A CTRL_REG1 Control Reg1 R/W ASLP_RATE1 ASLP_RATE0 DR2 DR1 DR0 0 F_READ ACTIVE 19–28 2B CTRL_REG2 Control Reg2 R/W ST RST — SMODS1 SMODS0 SLPE MODS1 MODS0 2C CTRL_REG3 Control Reg3 R/W — — WAKE_LNDPRT — WAKE_FF_MT 0 IPOL PP_OD 2D CTRL_REG4 Control Reg4 R/W INT_EN_ASLP — — INT_EN_LNDPRT — INT_EN_FF_MT 0 INT_EN_DRDY 2E CTRL_REG5 Control Reg5 R/W INT_CFG_ASLP — — INT_CFG_LNDPRT — INT_CFG_FF_MT 0 INT_CFG_DRDY 2F OFF_X X 8-bit offset R/W D7 D6 D5 D4 D3 D2 D1 D0 30 OFF_Y Y 8-bit offset R/W D7 D6 D5 D4 D3 D2 D1 D0 31 OFF_Z Z 8-bit offset R/W D7 D6 D5 D4 D3 D2 D1 D0 Note: Bits showing “—” can read as either 0 or 1, and these bits have no definition. MMA8653FC Sensors Freescale Semiconductor, Inc. 21 6.3 Data registers The following are the data registers for the MMA8653FC device. For more information about data manipulation in the MMA8653FC, see application note AN4083, Data Manipulation and Basic Settings for Xtrinsic MMA865xFC Accelerometers. • When accessing the 8-bit data, the F_READ bit (register 0x2A) is set, which modifies the auto-incrementing to skip over the LSB data. • When the F_READ bit is cleared, the 12-bit data is read, accessing all 6 bytes sequentially (X_MSB, X_LSB, Y_MSB, Y_LSB, Z_MSB, Z_LSB). 6.3.1 0x00: STATUS Data Status register Data Status register 0x00 reflects the real-time status information of the X, Y and Z sample data; it contains the X, Y, and Z data overwrite and data ready flag. These registers contain the X-axis, Y-axis, and Z-axis 12-bit output sample data (expressed as 2's complement numbers). Table 14. 0x00 STATUS: Data Status register (Read-Only) Back to Register Address Map Bit 7 ZYXOW Bit 6 ZOW Bit 5 YOW Bit 4 XOW Bit 3 ZYXDR Bit 2 ZDR Bit 1 YDR Bit 0 XDR Table 15. STATUS register bits Bit(s) 7 Field ZYXOW Description 6 ZOW Z-axis data overwrite 5 YOW Y-axis data overwrite 4 XOW X-axis data overwrite 3 ZYXDR Notes X, Y, Z-axis data overwrite • Set whenever a new acceleration data is produced before completing the retrieval of the previous set. This event occurs when the content of at least one acceleration data register (i.e., OUT_X, OUT_Y, OUT_Z) has been overwritten. • Cleared when the high bytes of the acceleration data (OUT_X_MSB, OUT_Y_MSB, OUT_Z_MSB) of all the channels are read. 0 No data overwrite has occurred (default) 1 Previous X, Y, or Z data was overwritten by new X, Y, or Z data before it (the previous X, Y, or Z data) was read For # = Z, Y, or X: • Set whenever a new acceleration sample related to the #-axis is generated before the retrieval of the previous sample. When this occurs, the previous sample is overwritten. • Cleared whenever the OUT_#_MSB register is read. 0 No data overwrite has occurred (default) 1 Previous Z-axis data was overwritten by new #-axis data before it (the previous #-axis data) was read X, Y, Z-axis new data ready • Set when a new sample for any of the enabled channels is available. • Cleared when the high-bytes of the acceleration data (OUT_X_MSB, OUT_Y_MSB, OUT_Z_MSB) of all the channels are read. 0 No new set of data ready (default) 1 A new set of data is ready 2 ZDR Z-axis new data available 1 YDR Y-axis new data available 0 XDR X-axis new data available For # = Z, Y, or X • Set whenever a new acceleration sample related to the #-axis is generated. • Cleared whenever the OUT_#_MSB register is read. 0 No new #-axis data ready (default) 1 New #-axis data is ready Table 16. 0x01 OUT_X_MSB: X_MSB register (Read-Only) Bit 7 XD9 Bit 6 XD8 Bit 5 XD7 Bit 4 XD6 Back to Register Address Map Bit 3 XD5 Bit 2 XD4 Table 17. 0x02 OUT_X_LSB: X_LSB register (Read-Only) Bit 7 XD1 Bit 6 XD0 Bit 5 0 Bit 4 0 Bit 1 XD3 Bit 0 XD2 Back to Register Address Map Bit 3 0 Bit 2 0 Bit 1 0 Bit 0 0 MMA8653FC 22 Sensors Freescale Semiconductor, Inc. Table 18. 0x03 OUT_Y_MSB: Y_MSB register (Read-Only) Bit 7 YD9 Bit 6 YD8 Bit 5 YD7 Bit 4 YD6 Back to Register Address Map Bit 3 YD5 Bit 2 YD4 Table 19. 0x04 OUT_Y_LSB: Y_LSB register (Read-Only) Bit 7 YD1 Bit 6 YD0 Bit 5 0 Bit 4 0 Bit 6 ZD8 Bit 5 ZD7 Bit 4 ZD6 Bit 3 0 Bit 2 0 Bit 6 ZD0 Bit 5 0 Bit 4 0 Bit 1 0 Bit 0 0 Back to Register Address Map Bit 3 ZD5 Bit 2 ZD4 Table 21. 0x06 OUT_Z_LSB: Z_LSB register (Read-Only) Bit 7 ZD1 Bit 0 YD2 Back to Register Address Map Table 20. 0x05 OUT_Z_MSB: Z_MSB register (Read-Only) Bit 7 ZD9 Bit 1 YD3 Bit 1 ZD3 Bit 0 ZD2 Back to Register Address Map Bit 3 0 Bit 2 0 Bit 1 0 Bit 0 0 • OUT_X_MSB, OUT_X_LSB, OUT_Y_MSB, OUT_Y_LSB, OUT_Z_MSB, and OUT_Z_LSB are stored in the autoincrementing address range of 0x01 – 0x06, to reduce reading the status followed by 10-bit axis data to 7 bytes. If the F_READ bit is set (0x2A bit 1), then auto-increment will skip over LSB registers (to access the MSB data only). This will shorten the data acquisition from seven bytes to four bytes. • The LSB registers can only be read immediately following the read access of the corresponding MSB register. — A random read access to the LSB registers is not possible. — Reading the MSB register and then the LSB register in sequence ensures that both bytes (LSB and MSB) belong to the same data sample, even if a new data sample arrives between reading the MSB and the LSB byte. MMA8653FC Sensors Freescale Semiconductor, Inc. 23 6.4 System status and ID registers 6.4.1 0x0B: SYSMOD System Mode register The System mode register indicates the current device operating mode. Applications using the Auto-SLEEP/WAKE mechanism should use the SYSMOD register to synchronize the application with the device operating mode transitions. Table 22. 0x0B SYSMOD: System Mode register (Read-Only) Bit 7 0 Bit 6 0 Bit 5 0 Bit 4 0 Back to Register Address Map Bit 3 0 Bit 2 0 Bit 1 SYSMOD1 Bit 0 SYSMOD0 Table 23. SYSMOD register Bit(s) Field 7–2 0 1–0 6.4.2 Description Reserved SYSMOD[1:0] System Mode 00 STANDBY mode (default) 01 WAKE mode 10 SLEEP mode 0x0C: INT_SOURCE System Interrupt Status register In the interrupt source register, the status of the various embedded features can be determined. • The bits that are set (logic ‘1’) indicate which function has asserted an interrupt. • The bits that are cleared (logic ‘0’) indicate which function has not asserted (or has deasserted) an interrupt. INT_SOURCE register bits are set by a low-to-high transition, and are cleared by reading the appropriate interrupt source register. For example, the SRC_DRDY bit is cleared when the ZYXDR bit (STATUS register) is cleared, but the SRC_DRDY bit is not cleared by simply reading the STATUS register (0x00), but is cleared by reading all the X, Y, and Z MSB data. Table 24. 0x0C INT_SOURCE: System Interrupt Status register (Read Only) Bit 7 SRC_ASLP Bit 6 0 Bit 5 0 Bit 4 SRC_LNDPRT Bit 3 0 Back to Register Address Map Bit 2 SRC_FF_MT Bit 1 0 Bit 0 SRC_DRDY MMA8653FC 24 Sensors Freescale Semiconductor, Inc. Table 25. INT_SOURCE register Bit(s) Field Description 7 SRC_ASLP Auto-SLEEP/WAKE interrupt status bit • WAKE-to-SLEEP transition occurs when no interrupt occurs for a time period that exceeds the userspecified limit (ASLP_COUNT). This causes the system to transition to a user-specified low ODR setting. • SLEEP-to-WAKE transition occurs when the user-specified interrupt event has woken the system; thus causing the system to transition to a user-specified high ODR setting. • Reading the SYSMOD register clears the SRC_ASLP bit. 1 An interrupt event that can cause a WAKE-to-SLEEP or SLEEP-to-WAKE system mode transition has occurred. 0 No WAKE-to-SLEEP or SLEEP-to-WAKE system mode transition interrupt event has occurred. (default) 6 0 5 0 4 SRC_LNDPRT 3 0 2 SRC_FF_MT 1 0 0 6.4.3 SRC_DRDY Landscape/Portrait Orientation interrupt status bit • SRC_LNDPRT bit is asserted whenever the NEWLP bit (PL_STATUS register) is asserted and the interrupt has been enabled. • SRC_LNDPRT bit is cleared by reading the PL_STATUS register. 1 An interrupt was generated due to a change in the device orientation status. 0 No change in orientation status was detected. (default) Freefall/Motion interrupt status bit • SRC_FF_MT bit is asserted whenever the EA bit (FF_MT_SRC register) is asserted and the FF_MT interrupt has been enabled. • SRC_FF_MT bit is cleared by reading the FF_MT_SRC register. 1 The Freefall/Motion function interrupt is active. 0 No Freefall or Motion event was detected. (default) Data Ready Interrupt bit status bit • SRC_DRDY bit is asserted when the ZYXOW and/or ZYXDR bit is set and the interrupt has been enabled. • SRC_DRDY bit is cleared by reading the X, Y, and Z data. 1 The X, Y, Z data ready interrupt is active (indicating the presence of new data and/or data overrun). 0 The X, Y, Z interrupt is not active. (default) 0x0D: WHO_AM_I Device ID register The device identification register identifies the part. The default value is 0x5A (for MMA8653FC). This value is programmed by Freescale before the part leaves the factory. For custom alternate values, contact Freescale. Table 26. 0x0D: WHO_AM_I Device ID register (Read-Only) Bit 7 0 Bit 6 1 Bit 5 0 Bit 4 1 Back to Register Address Map Bit 3 1 Bit 2 0 Bit 1 1 Bit 0 0 MMA8653FC Sensors Freescale Semiconductor, Inc. 25 6.5 Data configuration registers 6.5.1 0x0E: XYZ_DATA_CFG register The XYZ_DATA_CFG register sets the dynamic range. Table 27. 0x0E: XYZ_DATA_CFG register (Read/Write) Bit 7 0 Bit 6 0 Bit 5 0 Bit 4 0 Back to Register Address Map Bit 3 0 Bit 2 0 Bit 1 FS1 Bit 0 FS0 Table 28. XYZ Data Configuration register Bit(s) Field 7–2 0 1–0 FS[1:0] Description Output buffer data format using full scale 00 ±2 g (default) The default full scale value range is ±2 g. Table 29. Full-Scale Range FS1 FS0 Full-Scale Range 0 0 ±2 g 0 1 ±4 g 1 0 ±8 g 1 1 Reserved MMA8653FC 26 Sensors Freescale Semiconductor, Inc. 6.6 Portrait/Landscape configuration and status registers For more information about the different user-configurable settings and example code, see application note AN4083, Data Manipulation and Basic Settings for Xtrinsic MMA865xFC Accelerometers. 6.6.1 0x10: PL_STATUS Portrait/Landscape Status register To get updated information on any change in orientation, read the Portrait/Landscape Status register (read Bit 7, or read the other bits for more orientation data). For more about Portrait Up, Portrait Down, Landscape Left, Landscape Right, Back, and Front orientations, see Figure 6. The interrupt is cleared when reading the PL_STATUS register. Table 30. 0x10 PL_STATUS Register (Read-Only) Bit 7 NEWLP Bit 6 LO Bit 5 0 Back to Register Address Map Bit 4 0 Bit 3 0 Bit 2 LAPO[1] Bit 1 LAPO[0] Bit 0 BAFRO Table 31. PL_STATUS register Bit(s) 7 Field NEWLP 6 LO 5–3 0 2–1 LAPO[1:0](1) 0 BAFRO Description Landscape/Portrait status change flag • NEWLP is set to 1 after the first orientation detection after a STANDBY-to-ACTIVE transition, and whenever a change in LO, BAFRO, or LAPO occurs. • NEWLP bit is cleared anytime PL_STATUS register is read. 0 No change (default) 1 BAFRO and/or LAPO and/or Z-Tilt lockout value has changed Z-Tilt Angle Lockout 0 Lockout condition has not been detected (default) 1 Z-Tilt lockout trip angle has been exceeded. Lockout has been detected. Landscape/Portrait orientation 00 Portrait Up: Equipment standing vertically in the normal orientation (default) 01 Portrait Down: Equipment standing vertically in the inverted orientation 10 Landscape Right: Equipment is in landscape mode to the right 11 Landscape Left: Equipment is in landscape mode to the left. Back or Front orientation 0 Front: Equipment is in the front-facing orientation (default) 1 Back: Equipment is in the back-facing orientation 1. The default power-up state is BAFRO = 0, LAPO = 00, and LO = 0. • The orientation mechanism state change is limited to a maximum 1.25 g. The current position is locked if the absolute value of the acceleration experienced on any of the three axes is greater than 1.25 g. • LAPO, BAFRO, and LO continue to change when NEWLP is set. MMA8653FC Sensors Freescale Semiconductor, Inc. 27 6.6.2 0x11 Portrait/Landscape Configuration register The Portrait/Landscape Configuration register enables the portrait/landscape function and sets the behavior of the debounce counter. Table 32. 0x11 PL_CFG register (Read/Write) Bit 7 DBCNTM Bit 6 PL_EN Back to Register Address Map Bit 5 0 Bit 4 0 Bit 3 0 Bit 2 0 Bit 1 0 Bit 0 0 Table 33. PL_CFG register Bit(s) Field 7 DBCNTM 6 PL_EN 5–0 0 6.6.3 Description Debounce counter mode selection 0 Decrements debounce whenever the condition of interest is no longer valid. 1 Clears the counter whenever the condition of interest is no longer valid. (default) Portrait/Landscape detection enable 0 Portrait/Landscape Detection is disabled. (default) 1 Portrait/Landscape Detection is enabled. 0x12 Portrait/Landscape Debounce register The Portrait/Landscape Debounce register sets the debounce count for the orientation state transition. The minimum debounce latency is determined by the data rate (which is set by the product of the selected system ODR and PL_COUNT registers). Any transition from WAKE to SLEEP (or SLEEP to Wake) resets the internal Landscape/Portrait debounce counter. NOTE The debounce counter weighting (time step) changes, based on the ODR and the Oversampling mode. Table 36 explains the time step value for all sample rates and all Oversampling modes. Table 34. 0x12 PL_COUNT register (Read/Write) Bit 7 DBNCE[7] Bit 6 DBNCE[6] Bit 5 DBNCE[5] Back to Register Address Map Bit 4 DBNCE[4] Bit 3 DBNCE[3] Bit 2 DBNCE[2] Bit 1 DBNCE[1] Bit 0 DBNCE[0] Table 35. PL_COUNT register Bit(s) 7–0 Field DBCNE[7:0] Description Debounce Count value 0000_0000 (default) Table 36. PL_COUNT relationship with the ODR Max Time Range (s) Time Step (ms) ODR (Hz) Normal LPLN HighRes LP Normal LPLN HighRes LP 800 0.319 0.319 0.319 0.319 1.25 1.25 1.25 1.25 400 0.638 0.638 0.638 0.638 2.5 2.5 2.5 2.5 200 1.28 1.28 0.638 1.28 5 5 2.5 5 100 2.55 2.55 0.638 2.55 10 10 2.5 10 50 5.1 5.1 0.638 5.1 20 20 2.5 20 12.5 5.1 20.4 0.638 20.4 20 80 2.5 80 6.25 5.1 20.4 0.638 40.8 20 80 2.5 160 1.56 5.1 20.4 0.638 40.8 20 80 2.5 160 MMA8653FC 28 Sensors Freescale Semiconductor, Inc. 6.6.4 0x13: PL_BF_ZCOMP Back/Front and Z Compensation register The Z-Lock angle compensation bits fix the Z-lockout angle to 30° upon power up. The Back to Front trip angle is fixed to ±75°. Table 37. 0x13: PL_BF_ZCOMP register (Read only) Bit 7 0 Bit 6 1 Bit 5 0 Back to Register Address Map Bit 4 0 Bit 3 0 Bit 2 1 Bit 1 0 Bit 0 0 Table 38. PL_BF_ZCOMP register 6.6.5 Bit(s) Field 7–0 0100 0100 Description Notes 0x14: P_L_THS_REG Portrait/Landscape Threshold and Hysteresis register This register represents the Portrait-to-Landscape trip threshold register used to set the trip angle for transitioning from Portrait to Landscape mode and from Landscape to Portrait mode. This register includes a value for the hysteresis. Table 39. 0x14: P_L_THS_REG register (Read only) Bit 7 1 Bit 6 0 Bit 5 0 Bit 4 0 Back to Register Address Map Bit 3 0 Bit 2 1 Bit 1 0 Bit 0 0 Table 40. P_L_THS_REG register Bit(s) Field 7–0 1000 0100 Description Notes MMA8653FC Sensors Freescale Semiconductor, Inc. 29 6.7 Freefall/Motion configuration and status registers The freefall/motion function can be configured in either Freefall or Motion Detection mode via the OAE configuration bit (0x15: FF_MTG_CFG, bit 6). The freefall/motion detection block can be disabled by setting all three bits (ZEFE, YEFE, XEFE) to zero. Depending on the register bits ELE (0x15: FF_MTG_CFG, bit 7) and OAE (0x15: FF_MTG_CFG, bit 6), each of the freefall and motion detection block can operate in four different modes. 6.7.1 Motion and freefall modes 6.7.1.1 Mode 1: Freefall detection with ELE = 0, OAE = 0 In this mode, the EA bit (0x16: FF_MTG_CFG, bit 7) indicates a freefall event after the debounce counter is complete. The ZEFE, YEFE, and XEFE control bits determine which axes are considered for the freefall detection. Once the EA bit is set, and DBCNTM = 0, the EA bit can get cleared only after the delay specified by FF_MT_COUNT. This is because the counter is in decrement mode. If DBCNTM = 1, then the EA bit is cleared as soon as the freefall condition disappears, and will not be set again before the delay specified by FF_MT_COUNT has passed. Reading the FF_MT_SRC register does not clear the EA bit. The event flags (0x16) ZHE, ZHP, YHE, YHP, XHE, and XHP reflect the motion detection status (i.e., a high g event) without any debouncing, provided that the corresponding bits ZEFE, YEFE, and/or XEFE are set. 6.7.1.2 Mode 2: Freefall detection with ELE = 1, OAE = 0 In this mode, the EA event bit indicates a freefall event after the debounce counter. Once the debounce counter reaches the time value for the set threshold, the EA bit is set, and the EA bit remains set until the FF_MT_SRC register is read. When the FF_MT_SRC register is read, the EA bit and the debounce counter are cleared, and a new event can only be generated after the delay specified by FF_MT_CNT. The ZEFE, YEFE, and XEFE control bits determine which axes are considered for the freefall detection. While EA = 0, the event flags ZHE, ZHP, YHE, YHP, XHE, and XHP reflect the motion detection status (i.e., a high g event) without any debouncing, provided that the corresponding bits ZEFE, YEFE, and/or XEFE are set. The event flags ZHE, ZHP, YHE, YHP, XHE, and XHP are latched when the EA event bit is set. The event flags ZHE, ZHP, YHE, YHP, XHE, and XHP will start changing only after the FF_MT_SRC register has been read. 6.7.1.3 Mode 3: Motion detection with ELE = 0, OAE = 1 In this mode, the EA bit indicates a motion event after the debounce counter time is reached. The ZEFE, YEFE, and XEFE control bits determine which axes are taken into consideration for motion detection. Once the EA bit is set and if DBCNTM = 0, the EA bit can get cleared only after the delay specified by FF_MT_COUNT. If DBCNTM = 1, then the EA bit is cleared as soon as the motion high g condition disappears. The event flags ZHE, ZHP, YHE, YHP, XHE, and XHP reflect the motion detection status (i.e., a high g event) without any debouncing, provided that the corresponding bits ZEFE, YEFE, and/or XEFE are set. Reading the FF_MT_SRC does not clear any flags, nor is the debounce counter reset. 6.7.1.4 Mode 4: Motion detection with ELE = 1, OAE = 1 In this mode, the EA bit indicates a motion event after debouncing. The ZEFE, YEFE, and XEFE control bits determine which axes are taken into consideration for motion detection. Once the debounce counter reaches the threshold, the EA bit is set, and the EA bit remains set until the FF_MT_SRC register is read. When the FF_MT_SRC register is read, all register bits are cleared and the debounce counter are cleared and a new event can only be generated after the delay specified by FF_MT_CNT. While the bit EA is zero, the event flags ZHE, ZHP, YHE, YHP, XHE, and XHP reflect the motion detection status (i.e., a high g event) without any debouncing, provided that the corresponding bits ZEFE, YEFE, and/or XEFE are set. When the EA bit is set, these bits (ZHE, ZHP, YHE, YHP, XHE, XHP) keep their current value until the FF_MT_SRC register is read. MMA8653FC 30 Sensors Freescale Semiconductor, Inc. 6.7.2 0x15: FF_MT_CFG Freefall/Motion Configuration register This is the Freefall/Motion configuration register for setting up the conditions of the freefall or motion function. Table 41. 0x15 FF_MT_CFG register (Read/Write) Bit 7 ELE Bit 6 OAE Bit 5 ZEFE Back to Register Address Map Bit 4 YEFE Bit 3 XEFE Bit 2 0 Bit 1 0 Bit 0 0 Table 42. FF_MT_CFG register Bit(s) Field Description ELE Event Latch Enable: Event flags are latched into FF_MT_SRC register. ELE denotes whether the enabled event flag will to be latched into the FF_MT_SRC register or whether the event flag status in the FF_MT_SRC will indicate the real-time status of the event. • If ELE bit is set to 1, then the event flags are frozen when the EA bit gets set, and the event flags are cleared by reading the FF_MT_SRC source register. • Reading the FF_MT_SRC register clears the event flag EA and all FF_MT_SRC bits. 0 Event flag latch disabled (default) 1 Event flag latch enabled OAE Motion detect / Freefall detect flag selection Selects between Motion (logical OR combination) and Freefall (logical AND combination) detection. 0 Freefall flag (Logical AND combination) (default) 1 Motion flag (Logical OR combination) ZEFE Event flag enable on Z ZHFE enables the detection of a motion or freefall event when the measured acceleration data on Z channel is beyond the threshold set in FF_MT_THS register. • If ELE bit (FF_MT_CFG register) is set to 1, then new event flags are blocked from updating the FF_MT_SRC register. 0 Event detection disabled (default) 1 Raise event flag on measured acceleration value beyond preset threshold YEFE Event flag enable on Y event YEFE enables the detection of a motion or freefall event when the measured acceleration data on Y channel is beyond the threshold set in FF_MT_THS register. • If ELE bit (FF_MT_CFG register) is set to 1, then new event flags are blocked from updating the FF_MT_SRC register. 0 Event detection disabled (default) 1 Raise event flag on measured acceleration value beyond preset threshold 3 XEFE Event flag enable on X event XEFE enables the detection of a motion or freefall event when the measured acceleration data on X channel is beyond the threshold set in FF_MT_THS register. • If ELE bit (FF_MT_CFG register) is set to 1, then new event flags are blocked from updating the FF_MT_SRC register. 0 Event detection disabled (default) 1 Raise event flag on measured acceleration value beyond preset threshold 2–0 0 7 6 5 4 +8 g Low-g + Threshold (Freefall) 0g Low-g – Threshold (Freefall) –8 g Figure 14. FF_MT_CFG low-g threshold (freefall) MMA8653FC Sensors Freescale Semiconductor, Inc. 31 6.7.3 0x16: FF_MT_SRC Freefall/Motion Source register The Freefall/Motion Source register keeps track of the acceleration event that is triggering (or has triggered, if ELE bit in FF_MT_CFG register is set to 1) the event flag. In particular, EA is set to 1 when the logical combination of acceleration events flags specified in FF_MT_CFG register is true. This EA bit is used in combination with the values in INT_EN_FF_MT and INT_CFG_FF_MT register bits to generate the freefall/motion interrupts. • An X,Y, or Z motion is true when the acceleration value of the X or Y or Z channel is higher than the preset threshold value defined in the FF_MT_THS register. • An X, Y, and Z low event is true when the acceleration value of the X and Y and Z channel is lower than or equal to the preset threshold value defined in the FF_MT_THS register. Table 43. 0x16: FF_MT_SRC Freefall/Motion Source register (Read-Only) Bit 7 EA Bit 6 0 Bit 5 ZHE Bit 4 ZHP Bit 3 YHE Back to Register Address Map Bit 2 YHP Bit 1 XHE Bit 0 XHP Table 44. Freefall/Motion Source register Bit(s) Field 7 EA 6 0 5 4 3 2 1 0 Description Event Active flag 0 No event flag has been asserted (default) 1 One or more event flags has been asserted. See the description of the OAE bit to determine the effect of the 3-axis event flags on the EA bit. ZHE Z-Motion flag ZHE bit always reads zero if the ZEFE control bit is set to zero. 0 No Z motion event detected (default) 1 Z motion has been detected ZHP Z-Motion Polarity Flag ZHP bit always reads zero if the ZEFE control bit is set to zero. 0 Z event was positive g (default) 1 Z event was negative g YHE Y-Motion Flag YHE bit always reads zero if the YEFE control bit is set to zero. 0 No Y motion event detected (default) 1 Y motion has been detected YHP Y-Motion Polarity Flag YHP bit always reads zero if the YEFE control bit is set to zero. 0 Y event detected was positive g (default) 1 Y event was negative g XHE X-Motion Flag XHE bit always reads zero if the XEFE control bit is set to zero. 0 No X motion event detected (default) 1 X motion has been detected XHP X-Motion Polarity Flag XHP bit always reads zero if the XEFE control bit is set to zero. 0 X event was positive g (default) 1 X event was negative g MMA8653FC 32 Sensors Freescale Semiconductor, Inc. 6.7.4 0x17: FF_MT_THS Freefall and Motion Threshold register FF_MT_THS is the threshold register used to detect freefall motion events. • The unsigned 7-bit FF_MT_THS threshold register holds the threshold for the freefall detection where the magnitude of the X and Y and Z acceleration values is lower or equal than the threshold value. • Conversely, the FF_MT_THS also holds the threshold for the motion detection where the magnitude of the X or Y or Z acceleration value is higher than the threshold value. Table 45. 0x17 FF_MT_THS register (Read/Write) Bit 7 DBCNTM Bit 6 THS6 Bit 5 THS5 Back to Register Address Map Bit 4 THS4 Bit 3 THS3 Bit 2 THS2 Bit 1 THS1 Bit 0 THS0 Table 46. FF_MT_THS register Bit(s) Field Description 7 DBCNTM Debounce counter mode selection 0 Increments or decrements debounce (default) 1 Increments or clears counter. 6–0 THS[6:0] Freefall /Motion Threshold 000_0000 (default) The threshold resolution is 0.063 g/LSB and the threshold register has a range of 0 to 127 counts. The maximum range is to ±8 g. Note that even when the full scale value is set to ±2 g or ±4 g, the motion still detects up to ±8 g. The DBCNTM bit configures the way in which the debounce counter is reset when the inertial event of interest is momentarily not true. • When the DBCNTM bit is 1, the debounce counter is cleared to 0 whenever the inertial event of interest is no longer true as shown in Figure 15, (b). • While the DBCNTM bit is set to 0, the debounce counter is decremented by 1 whenever the inertial event of interest is no longer true (Figure 15, (c)) until the debounce counter reaches 0 or until the inertial event of interest becomes active. Decrementing the debounce counter acts as a median enabling the system to filter out irregular spurious events (which might impede the detection of inertial events). 6.7.5 0x18 FF_MT_COUNT Debounce register The Debounce register sets the number of debounce sample counts for the event trigger. Table 47. 0x18 FF_MT_COUNT register (Read/Write) Bit 7 D7 Bit 6 D6 Bit 5 D5 Bit 4 D4 Back to Register Address Map Bit 3 D3 Bit 2 D2 Bit 1 D1 Bit 0 D0 Table 48. FF_MT_COUNT register Bit(s) 7–0 Field D[7:0] Description Count value 0000_0000 (default) The Debounce register sets the minimum number of debounce sample counts that continuously match the detection condition selected by you for the freefall/motion event. When the internal debounce counter reaches the FF_MT_COUNT value, a freefall/motion event flag is set. The debounce counter will never increase beyond the FF_MT_COUNT value. The time step used for the debounce sample count depends on the ODR chosen and the Oversampling mode, as shown in Table 49. MMA8653FC Sensors Freescale Semiconductor, Inc. 33 Table 49. FF_MT_COUNT relationship with the ODR Max Time Range (s) Time Step (ms) ODR (Hz) Normal LPLN HighRes LP Normal LPLN HighRes LP 800 0.319 0.319 0.319 0.319 1.25 1.25 1.25 1.25 400 0.638 0.638 0.638 0.638 2.5 2.5 2.5 2.5 200 1.28 1.28 0.638 1.28 5 5 2.5 5 100 2.55 2.55 0.638 2.55 10 10 2.5 10 50 5.1 5.1 0.638 5.1 20 20 2.5 20 12.5 5.1 20.4 0.638 20.4 20 80 2.5 80 6.25 5.1 20.4 0.638 40.8 20 80 2.5 160 1.56 5.1 20.4 0.638 40.8 20 80 2.5 160 High g Event on all 3-axis (Motion Detect) Count Threshold (a) FF Counter Value FFEA High g Event on all 3-axis (Motion Detect) DBCNTM = 1 Count Threshold Debounce Counter Value (b) EA High g Event on all 3-axis (Motion Detect) DBCNTM = 0 Count Threshold Debounce Counter Value (c) EA Figure 15. DBCNTM bit function MMA8653FC 34 Sensors Freescale Semiconductor, Inc. 6.8 Auto-WAKE/SLEEP detection 6.8.1 0x29: ASLP_COUNT, Auto-WAKE/SLEEP Detection register (Read/Write) The ASLP_COUNT register sets the minimum time period of inactivity required to switch the part between Wake and Sleep status. At the end of the time period, the device switches its ODR rate automatically when the Auto-WAKE /SLEEP function is enabled. • Wake ODR is set by CTRL_REG1[DR] bits. • Sleep ODR is set by CTRL_REG1[ASLP_RATE] bits. • Auto WAKE/SLEEP function is enabled by asserting the CTRL_REG2[SLPE] bit. Table 50. 0x29 ASLP_COUNT register (Read/Write) Bit 7 D7 Bit 6 D6 Bit 5 D5 Back to Register Address Map Bit 4 D4 Bit 3 D3 Bit 2 D2 Bit 1 D1 Bit 0 D0 Table 51. ASLP_COUNT register Bit(s) Field 7–0 D[7:0] Description Duration value 0000_0000 (default) D7–D0 defines the minimum duration time needed to change the current ODR value from DR to ASLP_RATE. The time step and maximum value depend on the ODR chosen (as shown in Table 52). Table 52. ASLP_COUNT relationship with ODR Output Data Rate (ODR) Duration (sec) ODR Time Step (ms) ASLP_COUNT Step (ms) 800 Hz 0 to 81 1.25 320 400 Hz 0 to 81 2.5 320 200 Hz 0 to 81 5 320 100 Hz 0 to 81 10 320 50 Hz 0 to 81 20 320 12.5 Hz 0 to 81 80 320 6.25 Hz 0 to 81 160 320 1.56 Hz 0 to 162 640 640 For functional blocks that may be monitored for inactivity (to trigger the “return to SLEEP” event), see Table 53. Table 53. SLEEP/WAKE mode gates and triggers Will the event restart the timer and delay “Return to SLEEP”? Will the event WAKE from SLEEP? SRC_LNDPRT Yes Yes SRC_FF_MT Yes Yes SRC_ASLP No* No* SRC_DRDY No No Interrupt Source • Two interrupt sources can WAKE the device: Orientation and Motion/Freefall. One or more of these functions can be enabled. — To WAKE the device, the desired function(s) must be enabled in CTRL_REG4 register and set to WAKE-to-SLEEP in CTRL_REG3 register. — All enabled functions still run in SLEEP mode at the SLEEP ODR. Only the functions that have been selected for WAKE from SLEEP will actually WAKE the device (as configured in register 0x2C). — The Auto-WAKE/SLEEP interrupt does not affect the WAKE/SLEEP, nor does the data ready interrupt. MMA8653FC Sensors Freescale Semiconductor, Inc. 35 • MMA8653FC has two functions that can be used to keep the sensor from falling asleep: Orientation and Motion/Freefall. • Auto-SLEEP bit: 6.9 — If the Auto-SLEEP bit is disabled, then the device can only toggle between STANDBY and WAKE mode. — If Auto-SLEEP interrupt is enabled, then transitioning from ACTIVE mode to Auto-SLEEP mode (or vice versa) generates an interrupt. System and control registers NOTE Except for STANDBY mode selection, the device must be in STANDBY mode to change any of the fields within CTRL_REG1 (0x2A). 6.9.1 0x2A: CTRL_REG1 System Control 1 register CTRL_REG1 register configures the Auto-WAKE sample frequency, output data rate selection, and enables the fast-read mode and STANDBY/ACTIVE mode selection. Table 54. 0x2A CTRL_REG1 register (Read/Write) Bit 7 ASLP_RATE1 Bit 6 ASLP_RATE0 Bit 5 DR2 Back to Register Address Map Bit 4 DR1 Bit 3 DR0 Bit 2 0 Bit 1 F_READ Bit 0 ACTIVE Table 55. CTRL_REG1 register Bit(s) Field Description 7–6 ASLP_RATE[1:0] 5–3 DR[2:0] 2 0 1 F_READ Fast-read mode: Data format is limited to single byte 0 Normal mode (default) 1 Fast Read Mode 0 ACTIVE Full-scale selection 0 STANDBY mode (default) 1 ACTIVE mode Configures the Auto-WAKE sample frequency when the device is in SLEEP Mode. See Table 56. 00 (default) Data rate selection See Table 57. 000 (default) MMA8653FC 36 Sensors Freescale Semiconductor, Inc. Table 56. SLEEP mode rates ASLP_RATE1 ASLP_RATE0 Frequency (Hz) 0 0 50 0 1 12.5 1 0 6.25 1 1 1.56 Notes When the device is in Auto-SLEEP mode, the system ODR and the data rate for all the system functional blocks are overridden by the data rate set by the ASLP_RATE field. DR[2:0] bits select the Output Data Rate (ODR) for acceleration samples in WAKE mode. The default value is 000 for a data rate of 800 Hz. Table 57. System output data-rate selection DR2 DR1 DR0 ODR (Hz) Period (ms) Notes 0 0 0 800 1.25 default 0 0 1 400 2.5 0 1 0 200 5 0 1 1 100 10 1 0 0 50 20 1 0 1 12.5 80 1 1 0 6.25 160 1 1 1 1.56 640 The ACTIVE bit selects between STANDBY mode and ACTIVE mode. Table 58. Full-Scale selection using ACTIVE bit Active bit Mode 0 STANDBY (default) 1 ACTIVE • The F_Read bit selects between normal and Fast Read mode. When selected, the auto-increment counter will skip over the LSB data bytes. Data read from the FIFO will skip over the LSB data, reducing the acquisition time. • Note that F_READ can only be changed when FMODE = 00. • The F_READ bit applies for the output registers. MMA8653FC Sensors Freescale Semiconductor, Inc. 37 6.9.2 0x2B: CTRL_REG2 System Control 2 register CTRL_REG2 register is used to enable Self-Test, Software Reset, and Auto-SLEEP. In addition, it enables you to configure the SLEEP and WAKE mode power scheme selection (oversampling modes). Table 59. 0x2B CTRL_REG2 register (Read/Write) Bit 7 ST Bit 6 RST Bit 5 — Back to Register Address Map Bit 4 SMODS1 Bit 3 SMODS0 Bit 2 SLPE Bit 1 MODS1 Bit 0 MODS0 Table 60. CTRL_REG2 register Bit(s) Field 7 ST 6 RST 5 — 4–3 SMODS[1:0] 2 SLPE 1–0 MODS[1:0] Description Self-Test Enable Activates the self-test function. • When ST is set, the X, Y, and Z outputs will shift. 0 Self-Test disabled (default) 1 Self-Test enabled Software Reset RST bit is used to activate the software reset. • The reset mechanism is enabled in both STANDBY and ACTIVE modes. 0 Device reset disabled (default) 1 Device reset enabled. Could be 0 or 1. SLEEP mode power scheme selection See Table 61 and Table 62 00 (default) Auto-SLEEP enable 0 Auto-SLEEP is not enabled (default) 1 Auto-SLEEP is enabled. ACTIVE mode power scheme selection See Table 61 and Table 62 00 (default) When the reset bit is enabled, all registers are reset and are loaded with default values. Writing ‘1’ to the RST bit immediately resets the device, no matter whether it is in ACTIVE/WAKE, ACTIVE/SLEEP, or STANDBY mode. The I2C communication system is reset to avoid accidental corrupted data access. At the end of the boot process the RST bit is deasserted to 0. Reading this bit will return a value of zero. The (S)MODS[1:0] bits select which Oversampling mode is to be used, as shown in Table 61. The Oversampling modes are available in both WAKE Mode MOD[1:0] and also in the SLEEP Mode SMOD[1:0]. Table 61. (S)MODS Oversampling modes (S)MODS1 (S)MODS0 0 0 Power Mode Normal 0 1 Low Noise Low Power 1 0 High Resolution 1 1 Low Power MMA8653FC 38 Sensors Freescale Semiconductor, Inc. Table 62. MODS Oversampling modes averaging values at each ODR Mode ODR (Hz) 6.9.3 Normal (00) Low Noise Low Power (01) High Resolution (10) Low Power (11) Current A OS Ratio Current A OS Ratio Current A OS Ratio Current A OS Ratio 1.56 27 128 9 32 184 1024 6.5 16 6.25 27 32 9 8 184 256 6.5 4 12.5 27 16 9 4 184 128 6.5 2 50 27 4 27 4 184 32 15 2 100 49 4 49 4 184 16 26 2 200 94 4 94 4 184 8 49 2 400 184 4 184 4 184 4 94 2 800 184 2 184 2 184 2 184 2 0x2C: CTRL_REG3 Interrupt Control register CTRL_REG3 register is used to control the Auto-WAKE/SLEEP function by setting the orientation or Freefall/Motion as an interrupt to wake. CTRL_REG3 register also configures the interrupt pins INT1 and INT2. Table 63. 0x2C CTRL_REG3 register (Read/Write) Bit 7 — Bit 6 — Bit 5 WAKE_LNDPRT Back to Register Address Map Bit 4 — Bit 3 WAKE_FF_MT Bit 2 0 Bit 1 IPOL Bit 0 PP_OD Table 64. CTRL_REG3 register Bit(s) Field 7–6 — 5 WAKE_LNDPRT 4 — 3 WAKE_FF_MT 2 0 1 Wake from Orientation interrupt 0 Orientation function is bypassed in SLEEP mode. (default) 1 Orientation function interrupt can wake up system Could be 0 or 1. Wake from Freefall/Motion interrupt 0 Freefall/Motion function is bypassed in SLEEP mode. (default) 1 Freefall/Motion function interrupt can wake up Interrupt polarity Selects the polarity of the interrupt signals. When IPOL is 0 (default value), any interrupt event is signaled with a logical 0. 0 ACTIVE low (default) 1 ACTIVE high IPOL 0 6.9.4 Description Could be 0 or 1. PP_OD Push-Pull/Open-Drain selection on interrupt pad Configures the interrupt pins to Push-Pull or to Open-Drain mode. The Open-Drain configuration can be used for connecting multiple interrupt signals on the same interrupt line. 0 Push-Pull (default) 1 Open Drain 0x2D: CTRL_REG4 Interrupt Enable register (Read/Write) CTRL_REG4 register enables the following interrupts: Auto-WAKE/SLEEP, Orientation Detection, Freefall/Motion, and Data Ready. Table 65. 0x2D CTRL_REG4 Interrupt Enable register (Read/Write) Bit 7 INT_EN_ASLP Bit 6 — Bit 5 — Bit 4 INT_EN_LNDPRT Back to Register Address Map Bit 3 — Bit 2 Bit 1 INT_EN_FF_MT 0 Bit 0 INT_EN_DRDY MMA8653FC Sensors Freescale Semiconductor, Inc. 39 Table 66. CTRL_REG4 register Bit(s) 7 Field INT_EN_ASLP Auto-SLEEP/WAKE Interrupt Enable 6 — Could be 0 or 1. 5 — Could be 0 or 1. 4 INT_EN_LNDPRT Orientation (Landscape/Portrait) Interrupt Enable 3 — Could be 0 or 1. 2 INT_EN_FF_MT Freefall/Motion Interrupt Enable 0 INT_EN_DRDY Data Ready Interrupt Enable 6.9.5 Description 0 interrupt is disabled (default) 1 interrupt is enabled Note: The corresponding functional block interrupt enable bit enables the functional block to route its event detection flags to the system’s interrupt controller. The interrupt controller routes the enabled functional block interrupt to the INT1 or INT2 pin. 0x2E CTRL_REG5 Interrupt Configuration register (Read/Write) CTRL_REG5 register maps the desired interrupts to INT2 or INT1 pins. The system’s interrupt controller, shown in Figure 9, uses the corresponding bit field in the CTRL_REG5 register to determine the routing table for the INT1 and INT2 interrupt pins. • If the bit value is 0, then the functional block’s interrupt is routed to INT2. • If the bit value is 1, then the functional block’s interrupt is routed to INT1. One or more functions can assert an interrupt pin; therefore a host application responding to an interrupt should read the INT_SOURCE (0x0C) register, to determine the appropriate sources of the interrupt. Table 67. 0x2E: CTRL_REG5 Interrupt Configuration register Back to Register Address Map Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 INT_CFG_ASLP — — INT_CFG_LNDPRT — INT_CFG_FF_MT 0 INT_CFG_DRDY Table 68. 0x2E CTRL_REG5 register Bit(s) Field Description 7 INT_CFG_ASLP Auto-SLEEP/WAKE INT1/INT2 Configuration 6 — Could be 0 or 1. 5 — Could be 0 or 1. 4 INT_CFG_LNDPRT Orientation INT1/INT2 Configuration 3 — Could be 0 or 1. 2 INT_CFG_FF_MT Freefall/motion INT1/INT2 Configuration 1 0 0 INT_CFG_DRDY 0 Interrupt is routed to INT2 pin (default) 1 Interrupt is routed to INT1 pin Data Ready INT1/INT2 Configuration MMA8653FC 40 Sensors Freescale Semiconductor, Inc. 6.10 Data calibration registers The 2’s complement offset correction registers values are used to realign the Zero-g position of the X, Y, and Z-axis after the device is mounted on a board. The resolution of the offset registers is 1.96 mg/LSB. The 2’s complement 8-bit value would result in an offset compensation range ±250 mg for each axis. 6.10.1 0x2F: OFF_X Offset Correction X register Table 69. 0x2F OFF_X register (Read/Write) Bit 7 D7 Bit 6 D6 Bit 5 D5 Back to Register Address Map Bit 4 D4 Bit 3 D3 Bit 2 D2 Bit 1 D1 Bit 0 D0 Table 70. OFF_X register Bit(s) 7–0 6.10.2 Field D[7:0] Description X-axis offset value 0000_0000 (default) 0x30: OFF_Y Offset Correction Y register Table 71. 0x30 OFF_Y register (Read/Write) Bit 7 D7 Bit 6 D6 Bit 5 D5 Back to Register Address Map Bit 4 D4 Bit 3 D3 Bit 2 D2 Bit 1 D1 Bit 0 D0 Table 72. OFF_Y register Bit(s) 7–0 6.10.3 Field D[7:0] Description Y-axis offset value 0000_0000 (default) 0x31: OFF_Z Offset Correction Z register Table 73. 0x31 OFF_Z register (Read/Write) Bit 7 D7 Bit 6 D6 Bit 5 D5 Back to Register Address Map Bit 4 D4 Bit 3 D3 Bit 2 D2 Bit 1 D1 Bit 0 D0 Table 74. OFF_Z register Bit(s) 7–0 Field D[7:0] Description Z-axis offset value 0000_0000 (default) MMA8653FC Sensors Freescale Semiconductor, Inc. 41 7 Mounting Guidelines Surface mount printed circuit board (PCB) layout is a critical portion of the total design. The footprint for the surface mount packages must be the correct size to ensure proper solder connection interface between the PCB and the package. With the correct footprint, the packages will self-align when subjected to a solder reflow process. These guidelines are for soldering and mounting the Dual Flat No-Lead (DFN) package inertial sensors to PCBs. The purpose is to minimize the stress on the package after board mounting. The MMA865xFC digital output accelerometers use the DFN package platform. This section describes suggested methods of soldering these devices to the PCB for consumer applications. 7.1 Overview of soldering considerations Information provided here is based on experiments executed on DFN devices. They do not represent exact conditions present at a customer site. Therefore, this information should be used as guidance only and process and design optimizations are recommended to develop an application specific solution. It should be noted that with the proper PCB footprint and solder stencil designs, the package will self-align during the solder reflow process. 7.2 Halogen content This package is designed to be Halogen Free, exceeding most industry and customer standards. Halogen Free means that no homogeneous material within the assembly package shall contain chlorine (Cl) in excess of 700 ppm or 0.07% weight/weight or bromine (Br) in excess of 900 ppm or 0.09% weight/weight. 7.3 PCB mounting/soldering recommendations 1. 2. 3. 4. 5. 6. 7. The PCB land should be designed as Non Solder Mask Defined (NSMD) as shown in Figure 16. No additional via pattern underneath package. PCB land pad is 0.6 mm x 0.225 mm as shown in Figure 16. Solder mask opening = PCB land pad edge + 0.125 mm larger all around = 0.725 mm x 1.950 mm Stencil opening = PCB land pad – 0.05 mm smaller all around = 0.55 mm x 0.175 mm. Stencil thickness is 100 or 125 µm. Do not place any components or vias at a distance less than 2 mm from the package land area. This may cause additional package stress if it is too close to the package land area. 8. Signal traces connected to pads are as symmetric as possible. Put dummy traces on NC pads, to have same length of exposed trace for all pads. 9. Use a standard pick and place process and equipment. Do not use a hand soldering process. 10. Use caution when putting an assembled PCB into an enclosure, noting where the screw-down holes are and if any press-fitting is involved. It is important that the assembled PCB remain flat after assembly, to ensure optimal electronic operation of the device. 11. The PCB should be rated for the multiple lead-free reflow condition with max 260°C temperature. 12. No copper traces on top layer of PCB under the package. This will cause planarity issues with board mount. Freescale DFN sensors are compliant with Restrictions on Hazardous Substances (RoHS), having halide free molding compound (green) and lead-free terminations. These terminations are compatible with tin-lead (Sn-Pb) as well as tin-silver-copper (Sn-Ag-Cu) solder paste soldering processes. Reflow profiles applicable to those processes can be used successfully for soldering the devices. MMA8653FC 42 Sensors Freescale Semiconductor, Inc. 0.200 2x2 DFN Package 1.950 All measurements are in mm. 0.225 0.725 0.600 2.525 PCB landing pad Solder mask opening Package outline Figure 16. Package mounting measurements Table 75. Board mounting guidelines Description Value (mm) Landing Pad Width 0.225 Landing Pad Length 0.600 Solder Mask Pattern Width 0.725 Solder Mask Pattern Length 1.950 Landing Pad Extended Length 0.200 I/O Pads Extended Length 2.525 MMA8653FC Sensors Freescale Semiconductor, Inc. 43 8 Tape and Reel 8.1 Tape dimensions Figure 17. Carrier tape 8.2 Device orientation Reel Pin 1 location Carrier tape User direction of feed Sprocket holes Cover tape Figure 18. Device orientation on carrier tape MMA8653FC 44 Sensors Freescale Semiconductor, Inc. 9 Package Dimensions This drawing is located at http://cache.freescale.com/files/shared/doc/package_info/98ASA00301D.pdf. Figure 19. Case 98ASA00301D, 10-Lead DFN—page 1 MMA8653FC Sensors Freescale Semiconductor, Inc. 45 Figure 20. Case 98ASA00301D, 10-Lead DFN—page 2 MMA8653FC 46 Sensors Freescale Semiconductor, Inc. Figure 21. Case 98ASA00301D, 10-Lead DFN—page 3 MMA8653FC Sensors Freescale Semiconductor, Inc. 47 10 Revision History Table 76. Revision history for MMA8653FC Revision number Revision date 0 08/2012 • Initial release. 1.0 02/2013 • • • • • • • • • • • • • • • 2.0 06/2014 • Section 1.2: Updated Descriptions for Pins 3 and 4. • Section 6.9.2: Replaced contents of Table 64. 2.1 12/2014 • Section 6.74: Corrected value in paragraph following Table 46, was 0.63 to 0.063. 2.2 03/2015 • Section 5.8: Updated paragraph before Table 11. Description of changes Title and introductory text, changed 12-bit to 10-bit. Feature comparison table: Orientation Detection features (2) rewritten for clarification. Section 1: Topics reordered for clarification and consistency. Table 4: Self-Test Output Change, x, y, and z specification values changed. Tables 8, 9: Changed units to emg/LSB. Section 5.5: Freefall detection rewritten for clarification. Section 5.6 Orientation detection rewitten for clarification. Section 6.4: FIFO-related content deleted. Section 6.5.1: FIFO-related content deleted. Table 19: bit field values deleted. Section 6.7.4: rewritten for clarification. Section 6.8.2: replaced Figure 32. Table 32: FIFO-related content deleted. Section 6.10.1: FIFO-related content deleted. Note following Table 39: deleted as unnecessary. MMA8653FC 48 Sensors Freescale Semiconductor, Inc. How to Reach Us: Information in this document is provided solely to enable system and software Home Page: freescale.com implementers to use Freescale products. There are no express or implied copyright Web Support: freescale.com/support information in this document. licenses granted hereunder to design or fabricate any integrated circuits based on the Freescale reserves the right to make changes without further notice to any products herein. Freescale makes no warranty, representation, or guarantee regarding the suitability of its products for any particular purpose, nor does Freescale assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. “Typical” parameters that may be provided in Freescale data sheets and/or specifications can and do vary in different applications, and actual performance may vary over time. All operating parameters, including “typicals,” must be validated for each customer application by customer’s technical experts. Freescale does not convey any license under its patent rights nor the rights of others. Freescale sells products pursuant to standard terms and conditions of sale, which can be found at the following address: freescale.com/salestermsandconditions. Freescale and the Freescale logo are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. All other product or service names are the property of their respective owners. © 2015 Freescale Semiconductor, Inc. Document Number: MMA8653FC Rev. 2.2 03/2015