SCA1000

Preliminary SCA1000 and SCA1020 Series Accelerometer FEATURES • 2-axis measurement: SCA1000 for X - Y measurement and SCA1020 for Z - Y measurement • Available range ±1.7 g • Interchangeable with SCA610/SCA620 (see interchangeability drawing below) • Over damped sensing element to control frequency response • SMD DIL-12 lead-free component • Compatible with lead-free reflow soldering process • Advanced internal and external connection failure detection • Digitally activated electrostatic self-test • Continuous memory parity check • Single +5 V supply; two ratiometric analog voltage outputs • Serial Peripheral Interface (SPI) compatible digital output (11 bits) • Internal temperature sensor, accessible via SPI BENEFITS • Excellent reliability and stability over time and temperature • High resolution and low noise • Wide operating temperature range • Outstanding overload and shock durability APPLICATIONS • 2-axis acceleration measurements • 2-axis platform leveling • Inclination based position measurement • 360 ° vertical orientation measurement For customized product, please contact VTI Technologies ELECTRICAL CHARACTERISTICS Parameter Supply voltage Vdd (1 Current consumption Analog resistive output load Analog capacitive output load Digital output load SPI clock frequency AD conversion time Data transfer time @500 kHz clock 150 38 @ 500 kHz Vdd = 5 V; No load Vout to Vdd or Vss 10 20 1 500 Condition Min 4.75 Typ. 5.0 Max 5.25 5 Units V mA kOhm nF nF kHz µs µs PERFORMANCE CHARACTERISTICS Parameter Measuring range (2 Measuring direction relative to mounting plane (12 Zero point (3,12 Sensitivity (4,12 Zero point error over temperature (5 Sensitivity error over temperature (6 Typical non-linearity (7 Cross-axis sensitivity (10 Frequency response –3dB (8 Ratiometric error (9 Condition Nominal See note 12. Mounting position @ room temperature -25…85 °C typical -40…125 °C -25…85 °C typical -40…125 °C Over measuring range @ room temperature @ -40…125 °C Vdd = 4.75...5.25 V From DC...100 Hz FS SCA1000-D01 SCA1020-D02 ±1.7 “X”= parellel “Y” =parallel Vdd/2 1.2 ±70 ±100 ±3 ±4 ±20 3.5 50±30 Hz 2 80 11 ±1.7 “Z”= perpendicular “Y”= parallel Vdd/2 1.2 ±70 ±100 ±3 ±4 ±20 3.5 50±30 Hz 2 80 11 Units g V V/g mg mg % % mg % Hz % µg/ Hz Bits Output noise density (11 Digital output resolution VDD = 5.00V, UNLESS OTHERWISE SPECIFIED Note 1 Note 2 Note 3 Note 4 Note 5 Note 6 Note 7 Note 8 100 nF supply by-pass capacitor is needed. Measuring directions in parallel to mounting plane, arrows showing positive acceleration direction. Zero point specified as Voffset = Vout(0 g) [ V ]. See note 12. Sensitivity specified as Vsens = {Vout(+1 g) - Vout(-1 g)}/2 [ V/g ]. See note 12. Zero point error specified as Zero point error = {Vout(0 g) – Vdd/2} / Vsens [ g ] VSens = Nominal sensitivity Vdd/2 = Nominal offset. Sensitivity error specified as Sensitivity error = { [Vout(+1 g)-Vout(-1 g)] / 2 - Vsens_nom} / Vsens_nom x 100 % [% ] Vsens_nom = nominal sensitivity See note 12. From straight line through +1 g and -1 g points. The output has true DC (0 Hz) response. Note 9 The ratiometric error is specified as: RE = 100% x 1- Vout(@Vx) x 5.00V Vx Vout(@5V) Note 10 Note 11 Note 12 The cross-axis sensitivity determines how much acceleration, perpendicular to the measuring axis, couples to the output. The total crossaxis sensitivity is the geometric sum of the sensitivities of the two axis which are perpendicular to the measuring axis. The angular alignment error between channels 1 and 2 is included into the cross axis error. Typical figure. In addition, supply voltage noise couples to the output due to the ratiometric nature of the accelerometer. Measuring directions. Rev. 18 Jan 2005 VTI Technologies reserves the right to modify this specification without prior to notice. SCA1000 and SCA1020 Series MEASURING DIRECTIONS SCA1000 ( X - Y Configuration) SCA1020 ( Z - Y Configuration) X: +1 g Position Y: 0 g Position X: 0 g Position Y: 0 g Position X: -1 g Position Y: 0 g Position Z: +1 g Position Y: 0 g Position Z: 0 g Position Y: 0 g Position Z: -1 g Position Y: 0 g Position X: 0 g Position Y: +1 g Position X: 0 g Position Y: 0 g Position X: 0 g Position Y: -1 g Position Z: 0 g Position Y: +1 g Position Z: 0 g Position Y: 0 g Position Z: 0 g Position Y: -1 g Position ABSOLUTE MAXIMUM RATINGS Parameter Acceleration (powered or non powered) Supply voltage Voltage at input/output pins Storage temperature range Value 20 000 -0.3 V to +5.5 V -0.3 V to (Vdd+0.3 V) -55…125 Unit g V V °C D IMENSIONS PCB PAD LAYOUTS The accelerometer weighs < 1.2 g. The size of the part is approximately (w x h x l) 9 x 5 x 16 mm. Pin pitch is standard 100 mils. SENSING DIRECTION PART NUMBER SERIAL NUMBER Acceleration in the direction of the arrow will increase the output voltage. SCA1000 and SCA1020 Series ELECTRICAL CONNECTION RECOMMENDED CIRCUIT Pin# Pin Name I/O 1 2 3 4 5 6 7 8 9 10 11 12 ST_2 ST_1 Out_1 VDD MISO MOSI Out_2 VSS CSB SCK Input NC Output Input Output Power Input NC Input Input Output Power Connection Serial clock Factory only Master in slave out; data output Master out slave in; data input Channel 2 Output (Y-axis) Negative supply voltage (VSS) Chip select (active low) Factory only Self test input for Channel 2 Self test input for Channel 1 Channel 1 output (X or Z-axis) Positive supply voltage (VDD) Self test can be activated applying logic “1” (positive supply voltage level) to ST pin (pin 9 and 10). If ST feature is not used pins 9 and 10 must be left floating or connected to GND. INTERCHANGEABILITY WITH SCA610 / SCA620 When SCA1000 / 1020 is used in Analog mode and the PCB is designed correctly the SCA610 / 620 and SCA1000 / 1020 are interchangeable. If the PCB layout is designed for SCA1000 /1020, then SCA610 / 620 can be used for single axis applications. The output of SCA610 / 620 corresponds to the output of channel 1 in the SCA1000 / 1020. VTI Technologies Oy Myllynkivenkuja 6 P.O. Box 27 FI-01621 Vantaa Finland Tel. +358 9 879 181 Fax +358 9 879 18791 sales@vti.fi VTI Technologies Oy Frankfurt Branch Rennbahnstr. 72-74 D-60528 Frankfurt am Main Germany Tel. +49 69 6786 880 Fax +49 69 6786 8829 sales.de@vti.fi VTI Technologies, Inc. One Park Lane Blvd. Suite 804 - East Tower Dearborn, MI 48126 USA Tel. +1 313 425 0850 Fax +1 313 425 0860 sales@vtitechnologies.com