SCA21X0 VTI [VTI technologies], SCA21X0 Datasheet
SCA21X0
Related parts for SCA21X0
SCA21X0 Summary of contents
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Product Family Specification VTI Automotive Digital Accelerometer Platform SCA8X0 / 21X0 / 31X0 Accelerometers SCA8X0/21X0/3100 Series ...
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... Operation Modes .................................................................................................................8 2.1 Measurement mode ...................................................................................................................8 2.2 Temperature output ...................................................................................................................8 2.3 Self-diagnostic functions ..........................................................................................................8 2.3.1 Memory self-diagnostic .........................................................................................................................8 2.3.2 Signal path self-diagnostic ....................................................................................................................8 2.3.2.1 SCA8X0 – single axis accelerometers ..........................................................................................8 2.3.2.2 SCA21X0 and SCA31X0 – multi axis accelerometers ..................................................................8 2.4 Power Down mode.....................................................................................................................9 2.5 Recommended start-up sequence ...........................................................................................9 2.6 Recommended operation sequence ......................................................................................10 2.7 Recommended procedures or optional features ..................................................................11 2.7.1 SCA8x0/SCA21x0/SCA31x0 ..............................................................................................................11 2.7.1.1 Read back procedure ..................................................................................................................11 2.7.1.2 Checksum during operation ...
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... SPI Interface ......................................................................................................................20 4.1 Output of Acceleration Data ...................................................................................................21 4.1.1 Register read operation ......................................................................................................................22 4.1.2 Decremented register read operation .................................................................................................22 4.1.3 MOSI data of SPI commands .............................................................................................................23 4.2 Error Conditioning ...................................................................................................................23 4.2.1 FRME-bit .............................................................................................................................................23 4.2.2 PORST-bit...........................................................................................................................................23 4.2.3 ST-bit (SCA21X0 / 3100) ....................................................................................................................24 4.2.4 SAT-bit (SCA21X0 / 3100)..................................................................................................................24 4.2.5 aPAR-bit (SCA21X0 / 3100) ...............................................................................................................24 4.2.6 dPAR-bit..............................................................................................................................................25 4.2.7 Fixed bits.............................................................................................................................................25 4.2.8 Output data .........................................................................................................................................25 5 Electrical Characteristics .................................................................................................26 5.1 Absolute maximum ratings.....................................................................................................26 5.2 Power Supply ...........................................................................................................................26 5 ...
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Tape and reel specifications...................................................................................................34 7 Contact Information ..........................................................................................................35 8 Document Change Control...............................................................................................36 VTI Technologies Oy www.vti.fi Doc. Nr. 82 694 00 C SCA8X0/21X0/3100 Series 4/35 ...
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General Description 1.1 Introduction VTI Automotive Digital Accelerometer Platform is an accelerometer product concept based on VTI capacitive 3D-MEMS technology. The VTI ADP platform integrates high accuracy micromechanical acceleration sensing together with a flexible SPI digital interface. The products within ...
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... SPI interface. In single axis products there is also Pulse Width Modulation output available. In addition to the supply voltage filtering the component does not require any other components to be connected to the device. Block diagram of SCA8X0/SCA21X0/31X0 1.4.1 Sensing element The sensing element of the product is manufactured by using VTI Technologies proprietary bulk 3D-mems process enabling a robust, stable and low noise capacitive sensor ...
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Analog to digital conversion Analog voltage information is amplified and filtered and converted into digital information for signal processing inside the ASIC. 1.4.5 Signal conditioning and filtering The block filters and conditions the measurement information needed for the application ...
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... By following the output of the device on SPI interface it is possible to detect failures through the signal path. 2.3.2.2 SCA21X0 and SCA31X0 – multi axis accelerometers 2.3.2.2.1 Start-up Self Test (STS) During the application start up or when the accelerometer is affected by the gravity force only it is possible to detect possible sensing element anomalies by applying a start up self test ...
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Power Down mode For low power applications it is possible to set the accelerometer into power down mode. During the power down mode the power consumption is minimized inside the device. This is achieved by stopping the internal clocks ...
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... Table 3: SCA21X0 and SCA31X0 start up sequence Item Procedure 1 Set Vdd=3.0...3.6V 2 Wait 35ms 3 Read INT_STATUS 4 Write CTRL=00001010 (a) or CTRL=00001000 (b) or CTRL=00000000 (c) 5 Wait 10ms 6 Read CTRL 7 Read Z_MSB, Z_LSB, Y_MSB, Y_LSB, X_MSB, X_LSB 2.6 Recommended operation sequence Table 4: Reading of the acceleration data Item ...
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... Product family components have different features, which are not required during normal operation. However, they are recommended in some cases if they are seen important from system perspective. 2.7.1 SCA8x0/SCA21x0/SCA31x0 2.7.1.1 Read back procedure It is recommended to read back every write command to compare read data to the write command. ...
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... Monitoring this data it is possible to determine product frequency response and check product timing properties. 3 Addressing Space Table 5 presents the registers of SCA8X0, SCA21X0 and SCA31X0 products. Table 5: Register address space Addr Name ...
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X_MSB Address: 5h Bits Mode 7:0 R 3.1.2 Y axis acceleration output 3.1.2.1 Y_LSB Address: 6h Bits Mode 7:0 R 3.1.2.2 Y_MSB Address: 7h Bits Mode 7:0 R 3.1.3 Z axis acceleration output 3.1.3.1 Z_LSB Address: 8h Bits Mode ...
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... If self-test (checksum, STC, STS) alarms it sets ST bit in SPI frame and forces output data to value 7FFF'hex (checksum fail value FFFF'hex (STC/STS alarm). In SCA21X0/SCA31X0 there is also possible to use 1-extra lsb bit (b1) for calculation to improve resolution. In that case acceleration bits can be converted to mg acceleration (Acc) using following equation ⎡ ...
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... In SCA8X0 acceleration bits can be converted to mg acceleration (Acc) using following equation [ [ ] 1000 = − ⋅ + ⋅ Acc 325 and in SCA21X0/SCA31X0 ⎡ − ⋅ + ⋅ 1000 = ⎢ Acc mg + ⋅ ...
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... TEMP_LSB registers in decimal format, bits(t9:0 temperature slope factor specified SCA21X0 and SCA31X0 offset of temperature data is factory calibrated but sensitivity of the temperature data varies from part to part. Temperature data is in unsigned format and 13 bits (13:1) of TEMP_MSB/TEMP_LSB are used for temperature. Here is presented temperature calculation using 10bit but 3-extra LSB bit can be used to improve resolution in noise sense if needed ...
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... Analog test mode status 1 – Test mode is active 0 – Test mode is not active 0 CSMERR EEPROM Checksum Error. In SCA21X0/SCA31X0 ST bit of SPI frame is also set if CSMERR is set. 0 FRME SPI frame error. Bit is reset, when next correct SPI frame is received. Bit is also visible in SPI frame ...
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... SPI command. Test is done automatically during start-up. Set other bits to zero in CTRL register by previous SPI command before starting memory self-test by CTRL.MST command. Use STATUS.CSMERR for test result monitoring and in SCA21X0/SCA31X0 ST bit in SPI frame. 0 ST_CFG Self-test configuration. SCA8X0: Select direction of mass deflection. ...
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... Identification registers 3.3.1 Revision ID (REVID) Address: 0h Bits Mode 7 SCA8X0 2) SCA21X0/SCA31X0 3.3.2 Component ID (ID) Address: 27h Bits Mode 7:0 RW The ID register contains information about the product version and value is loaded from non- volatile memory. Each VTI Automotive Digital Accelerometer Platform product will have a unique identification number ...
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... The SPI interface of VTI automotive series is designed to support almost any micro controller that uses software implemented SPI. However it is not designed to support any particular hardware implemented SPI found in many commercial micro controllers. SCA8X0/SCA21X0/SCA31X0 accelerometer operates always as a slave device in the master-slave operation mode. The data transfer between the master (µ ...
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SPI frame format and transfer protocol is presented in Figure 3. Figure 3: SPI frame format • MOSI • A5:A0 • RB/W • aPAR • DI7:DI0 • MISO • Bit 1 • FRME • Bit 3-5 status bits • PORST ...
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... DOUT register's content is shifted out without parity bits. Parity bit is calculated and transferred only for the first data frame. From X_LSB register address the SCA21X0/SCA31X0 jumps to Z_MSB. Decremented reading is possible only for registers X_LSB ... Z_MSB in SCA21X0 and SCA31X0 series. ...
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... FRME-bit While sending a frame, if CSB is raised to 1 before sending 16 SCKs, the frame is considered invalid. In SCA8X0 the frame error is raised if number of SCK pulses is not 16. In SCA21X0/3100 the frame error is raised only if number of SCK pulses is not divisible support decremented mode reading. When an invalid frame is received, the last command is simply ignored and the register contents are left unchanged ...
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... SAT bit is not defined in SCA8X0 series, but output saturates to the calibrated level. For example acceleration output data of SCA8x0 2 g products saturates to 2.27 g. 4.2.5 aPAR-bit (SCA21X0 / 3100) aPAR is odd parity bit of input address+RB/W-bit. Master write it and slave check that bit. • If there is parity error and RB/W='1', write command is ignored and frame error bit is set to STATUS-register and to SPI frame. Next correct SPI frame will zero this bit. • ...
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... Saturation: When acceleration exceeds measurement range, the output data is saturated to specified positive or negative full-scale. 3. Self-diagnostic failure: In SCA21X0 and 31X0 the ST bit in SPI frame is set when memory diagnostic or signal path diagnostic functions fail. Furthermore acceleration output data is forced to 7FFF'hex if memory diagnostic fails or to FFFF'hex if signal path diagnostic functions (STC/STS) fail ...
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Electrical Characteristics All voltages are referenced to ground. Currents flowing into the circuit have positive values. 5.1 Absolute maximum ratings The absolute maximum ratings of Digital Family are presented in Table 11 below. Table 11: Absolute maximum ratings Parameter ...
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SCK Frequency Terminal MOSI, SCK 6 Time from changing MOSI (10%, 90%) to SCK (90%) . Data setup 1 time 7 Time from SCK (90%) to changing MOSI (10%, 90%) . Data hold time 1 Terminal MISO, CSB 8 ...
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Application information 6.1 Package dimensions The package dimensions are presented in the Figure 7 below (measures in mm with ±0.1 mm tolerance). The part weights < 0.35 g. Figure 7: Package dimensions VTI Technologies Oy www.vti.fi Doc. Nr. 82 ...
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Output to Angle Conversion Product output is function of sin and it can be transferred to angle using the following equation for conversion: ⎛ Output α ⎜ ⎜ = arcsin ⎝ Sensitivit Where Output is output in g, Offset ...
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Measuring Directions 1 X [mg ARCSIN( [mg ARCSIN( [mg] 1000 o ARCSIN( [mg ARCSIN( [mg] 0 ...
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Pin Description Figure 8: Component pinout Table 12: Component pinout No. Name Type 1 Reserved 2 Reserved 3 AVSS AI 4 AVDD AI 5 CSB DI 6 MISO ZO 7 SCK DI 8 ...
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... Avoid crossing of AVDD path with digital signal especially between serial resistance R1 and AVDD pin 10 Do not route digital signals under the component on 2nd layer VTI Technologies Oy www.vti.fi Specified operation voltage (VDD) range 3.05...3 Ω SCA8x0 SCA21x0 C6 10 µF SCA3100 ...
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Figure 10: Recommended PWB layout for product family components with SPI interface (Top layer, Not actual size, for reference only) Figure 11: Recommended PWB layout for product family components with SPI interface (2nd layer, Not actual size, for reference only) ...
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Recommended PWB pad layout is presented in the Figure 12 below (dimensions in mm). Figure 12: Component pad layout 6.7 Assembly instructions The Moisture Sensitivity Level (MSL) of the component is 3 according to the IPC/JEDEC J-STD- 020C. Please refer ...
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Contact Information Finland (head office) VTI Technologies Oy P.O. Box 27 Myllynkivenkuja 6 FI-01621 Vantaa Finland Tel. +358 9 879 181 Fax +358 9 8791 8791 E-mail: sales@vti.fi Japan VTI Technologies Oy Tokyo Office Tokyo-to, Minato-ku 2-7-16 Bureau Toranomon ...