SCA1000-D01

SCA1000-D01 MURATA | Alldatasheet

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Technical content

Murata Electronics Oy 1/18 P R O D U C T S P E C I F I C A T I O N F O R X Y - D U A L A X I S A C C E L E R O M E T E R S C A 1 0 0 0 – D 0 1

Murata Electronics Oy 2/18 Table of Contents

1 General description

silicone gel and lid. The sensor has 12 SMD legs (Gull-wing type). Figure 1. Block diagram of the SCA1000

1.2 SCA1000 family Accelerometer Features

• Single +5V supply
• Wide load driving capability
• Serial Peripheral Interface (SPI) compatible
• Provides digital output for both channels
• Supports testing and programming
• Non-volatile programming features
• Factory programmable filter settings ( 400Hz, 1 kHz, WB, Ext_C )
• Offset and sensitivity calibration
• Linear temperature compensation
• Enhanced failure detection features
• True self test by deflecting the sensing elements’ proof mass by electrostatic force. Deflection voltage is adjustable with two memory bits for both channels. The self-test is channel specific, and separately activated for both channels by digital on-off commands via dedicated pins or via SPI bus.
• Continuous sensing element interconnection failure check

2 Electrical specifications

2.1 Electrical Connection

12 SCK

1 SCK Input Serial clock

2 NC NC NC

3 MISO Output Master in slave out; data output

4 MOSI Input Master out slave in; data input

5 Out_2 Output Y axis Output (Ch 2)

6 VSS Power Negative supply voltage (V SS )

7 CSB Input Chip select (active low)

8 NC NC NC

9 ST_2 Input Self test input for Y axis (Ch 2)

10 ST_1 / Test_in Input Self test input for X axis (Ch 1 ) / Analog t est input

11 Out_1 Output X axis output (Ch 1)

12 VDD Power Positive supply voltage (V DD )

Figure 2. Pin layout and description of the SCA1000

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2.1.1 Recommended connection when SPI interface is used

2.1.2 Recommended connection when analog output is used

When SCA1020 is used in Analog mode and the PCB is designed correctly the SCA610 / 620 and SCA1020 are interchangeable. If the PCB layout is designed for SCA1020, then SCA610 / 620 can be used for single axis applications. Pins 1, 2, 3, 4 and 8 can be connected to GND (pins 2 and 8 can be connected also to Vdd) but for the best EMC performance these pins should be left floating. CSB pin can be pulled up but it is recommended to left floating. The output of SCA610 / 620 corresponds to the output of channel 1 in the SCA1020 6 7 OUT_2 VSS CSB NC ST_2 ST_1 OUT_1 VDD Vdd (+5V) Min 100n FX Y Recommended SPI-Output connection on PCB Chip select Serial Clock Data Out Data In 6 7 OUT_2 VSS CSB NC ST_2 ST_1/Test_i n OUT_1 VDD Vdd (+5V) Out 1 (Z) Out 2 (Y) Self-Test 1 Self-Test 2 Min 100nF Z Y Recommended Analog output connection on PCB SCA610 or SCA620 connected to the SCA1020 lay-out

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2.1.3 Recommended EMC protection circuitry

The purpose of the following recommendation is to give generic EMC protection guidelines for the SCA1020. EMC susceptibility is highly dependent on the PCB layout and therefore the component values given here can be different depending on the actual PCB layout. With the following circuitry and properly designed PCB the part will pass 200V/m EMC susceptibility tests. Please note that only channel 1 output protection circuitry is presented. Similar kind of circuit must be also at the channel 2 output.

2.2 Absolute maximum ratings

Supply voltage (V DD ) -0.3 V to +5.5V (continuous) -0.3V to 7V (5 seconds during 1 minutes cycle ) Voltage at input / output pins -0.3V to (V DD + 0.3V) ESD HBM (Human Body Model) ±2kV CDM (Charged Device Model) ±500V Storage temperature -55 °C to +125 °C Operating temperature -40 °C to +125 °C Mechanical shock Drop from 1 meter on a concrete su rface. Out 1 (Z) 6 7 OUT_2 VSS CSB NC ST_2 ST_1/Test_i n OUT_1 VDD Vdd (+5V) Out 2 (Y) Self-Test 1 Self-Test 2 Min 100nF Z Y Recommended EMC protection circuitry Vdd (+5V) GND 68pF 68pF 10 ohm

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2.3 Electrical Specification of the SCA1000 – D01

2.3.1 Analog Output

Vdd = 5.00V and ambient temperature (23° C ±5° C) unless otherwise specified . . KPC (16 Parameter Condition Min. Typ Max. Units X axis (Out_1) Measuring range (1 Nominal -1.7 +1.7 g (2 Y axis (Out_2) Measuring range (1 Nominal -1.7 +1.7 g (2 Supply voltage Vdd 4.75 5.0 5.25 V <CC> Current consumption Vdd = 5 V; No load 5.0 mA Operating temperature -40 +125 °C Resistive output load (Analog Output) Vout to Vdd or Vss 10 kOhm Capacitive load (Analog Output) Vout to Vdd or Vss 20 nF Min. output voltage; Vdd = 5V 10k from Vout to Vdd 0 0.25 V Max. output voltage; Vdd = 5V 10k from Vout to Vss 4 .75 5.00 V <CC> X axis (Out_1) Offset (output at 0g) (3, 13 @ room temperature Vdd/2 V <CC> X axis (Out_1) Sensitivity (4, 13 @ room temperature 0.24 x Vdd V/g <SC> X axis (Out_1) Offset Error (output at 0g) (5, -40...+105 °C -40…+125 °C -80 -100 +80 +100 mg <SC> X axis (Out_1) Sensitivity error (6, 13 -40...+105 °C -40...+125 °C <CC> Y axis (Out_2) Offset (output at 0g) (3, 13 @ room temperature Vdd/2 V <CC> Y axis (Out_2) Sensitivity (4, 13 @ room temperature 0.24 x Vdd V/g <SC> Y axis (Out_2) Offset Error (output at 0g) (5, -40...+105 °C -40…+125 °C -80 -100 +80 +100 mg <SC> Y axis (Out_2) Sensitivity error (6, 13 -40...+105 °C -40...+125 °C Typical non-linearity (7 Range = -1g...+1g -20 - +20 mg X axis (Out_1) Frequency response -3dB (8 20 50 80 Hz Y axis (Out_2) Frequency response -3dB (8 20 50 80 Hz <SC> Cross-axis sensitivity (10 @ room temperature 3.5 % Output noise (11 From DC...4kHz 5 mVrms Start-up delay Reset and parity check 10 ms Self test input pull down current Vdd = 5V 10 21 30 µ A T1: T st-on (14 Self test ON period. Controlled externally by user 10 100 ms T2: Tsat.del. (14 Saturation delay. Time when element beam remains still out from linear operating range. 20 ms T3: T recov. (14 Recovery time when element is back in linear operating range 50 ms T4: T stab. (14 = T2+T3 Stabilisation time, when self test is released. 70 ms T5: T r (14 Rise time during self test, when Vout reach V2 10 ms V2 (14 Vout during self test 4.75 V V3 (14, 15 Stabilised output voltage after self test is released. 0.95* V1 1.05 *

Murata Electronics Oy 8/18 Note 1. The measuring range is limited only by the sensitivity, offset and supply voltage rails of the device Note 2. 1g = 9.82m/S Note 3. Offset specified as Voffset = Vout(0g) [ V ]. See note 13. Note 4. Sensitivity specified as Vsens = {Vout(+1g) - Vout(-1g)}/2 [ V/g ]. See note 13 Note 5. Offset error specified as Offset Error = {V out(0g) - Vdd/2} / Vsens [ g ] Vsens = Nominal sensitivity Vdd/2 = Nominal offset See note 13. Note 6. Sensitivity error specified as Sensitivity Error = { [Vout(+1g) - Vout(-1g)] / 2 - Vsens} / Vsens x 100% [% ] Vsens = Nominal sensitivity See note 13. Note 7. From straight line through -1g and +1g. Note 8. The frequency response is determined by the sensing element’s internal gas damping. The output has true DC (0Hz) response. Note 9. The ratiometric error is specified as. RE Vout Vx V Vx Vout V= × − 100% 1 5 00 (@ ) . (@ ) Note 10. The cross-axis sensitivity determines how much acceleration, perpendicular to the measuring axis, couples to the output. The total cross-axis sensitivity is the geometric sum of the sensitivities of the two axes that are perpendicular to the measuring axis. Note 11. In addition, supply voltage noise couples to the output due to the ratiometric nature of the accelerometer. Note 12. The self-test will increase the output voltage. The output will go to Vdd rail. The purpose of the self-test is to check out the total functionality of the sensor. It is not meant for calibration or auto zeroing. Note 13. Measuring positions

Murata Electronics Oy 9/18 Note 14. Self-test waveforms: Note 15. V1= Initial output Voltage before self-t est activation V3= Output voltage after self-test has been remove d and after stabilization time. Please note that the error band specified for V3 is to guarantee that the output is within 5% of the initial value after the specified stabilization time. After longer time V1=V3. Note 16 CC= Critical Characteristics. Must be 100% monitored during production SC= Significant Characteristic. The process capabil ity (Cpk) must be better than 1.33, which allows sample based testing. If process is not capable the part will be 100% tested

2.3.2 Digital Output

Vdd = 5.00V and ambient temperature unless otherwise specified . Parameter Condition Min. Typ Max. Units Output load @500kHz 1 nF SPI clock frequency 500 kHz Internal A/D conversion time 150 µ s Data transfer time @500kHz 38 µ s Vout 0 V Time [ ms ] T1 T2 T3 V1 V2 V3 ST pin voltage 0 V 5 V

3 SPI Interface

integrated circuit that receives the SPI clock from the master. Figure 4. Typical SPI connection performed serially with four wire system.

• commands and data are shifted MSB first LSB last
• each output data/status-bits are shifted out on th e falling edge of SCK (MISO line)
• each bit is sampled on the rising edge of SCK (MOS I line)

• after the device is selected with CSB going low, a n 8-bit command is received. The command defines the operations to be performed
• the rising edge of CSB ends all data transfer and resets internal counter and command register
• if an invalid command is received, no data will be shifted into chip and the MISO will remain in high impedance state until the falling edge of CSB. This will reinitialize the serial communication.
• to be able to perform any other command than those listed in Table 1. SPI commands, the lock register content has to be set correctly. If other command is feed without correct lock register content, no data will be shifted into chip and the MISO will remain in high impedance state until the falling edge of CSB.
• data transfer to MOSI continues right after the co mmand is received in all cases where data is to be written to ASIC’s internal registers
• data transfer out from MISO starts with a falling edge of SCK right after the last bit of SPI command is sampled in on the rising edge of SCK
• maximum data transfer speed exceeds 500 kHz clock rate SPI command can be an individual command or a combination of command and data. In the case of combined command and data, the input data follows uninterruptedly the SPI command and the output data is shifted out parallel with the input data. 7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0 CSB SCK M ISO M OSI 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 H IGH IM PED ANCE COM M AND DATA IN D ATA OU T

Figure 5. One command and data transmission over t he SPI used in the final application.

3.1 DC characteristics of SPI interface

Supply voltage is 5 V unless otherwise noted. Current flowing into the circuit have positive values. Table 1. DC characteristics of SPI interface

3.2 AC characteristics of SPI interface

Table 2. AC characteristics of SPI interface Figure 6. SPI bus timing diagram

3.3 SPI Commands

available to end-user is presented in Table 3. Table 3. SPI commands operation, MEAS command is exit command from Self-Test. temperature data register during RWTR command and hence all zeros is recommended. are the expected values during normal operation. Table 4. Status register bit definitions

direction. X-channel self-test is de-activated by giving MEAS command. direction. Y-channel self-test is de-activated by giving MEAS command. bit digital word, which is feed out MSB first and LSB last. (See Figure 7). Figure 7. RDAX command and data transmission over the SPI converted Y-channel acceleration signal which is stored in acceleration data register Y. Acceleration Sensor ASIC, Digital Specification.

4 Mechanical specification (Reference only)

Co-planarity error 0.1mm max.

4.1 Dimensions (Reference only)

Figure 8. Mechanical dimensions of the SCA1000

5 Mounting

normal SMD pick-and-place equipment. 3° C/second max. 3° C/second max. Figure 9. Recommended SCA1000 body temperature prof ile during reflow soldering. Note. Preheating time and temperatures according t o solder paste manufacturer.

The Moisture Sensitivity Level of the part is 3 according to the IPC/JEDEC J-STD-020B. customer’s end is 168 hours. Maximum soldering temperature is 250 °C/40sec. Figure 10. Recommended PCB lay-out

• It is important that the part is parallel to the P CB plane and that there is no angular alignment error from intended measuring direction during assembly process.
• 1° mounting alignment error will increase the cross-axis sensitivity by 1.7%
• 1° mounting alignment error will change the output by 17mg
• To achieve the highest accuracy and to minimize re sonance, it is recommended to glue the accelerometer to the PCB before soldering
• Wave soldering is not recommended.
• A supply voltage by-pass capacitor (>100nF) must b e used and located as close as possible to the Vdd and GND pins.
• Note: When the accelerometer is oriented in such a way that the arrow points toward the earth, the output will decrease. Please also note that you can rotate the part around the measuring axis for optimum mounting location.