SCA103T-D04-1

SCA103T Series Data Sheet THE SCA103T DIFFERENTIAL INCLINOMETER SERIES The SCA103T Series is a 3D-MEMS-based single axis inclinometer family that uses the differential measurement principle. The high calibration accuracy combines extremely low temperature dependency, high resolution and low noise together with a robust sensing element design, to make the SCA103T an ideal choice for high accuracy leveling instruments. The Murata inclinometers are insensitive to vibration due to having over damped sensing elements plus they can withstand mechanical shocks of 20000 g. Features           Measuring ranges ±15° SCA103T-D04 and ± 30° SCA103T-D05 0.001° resolution (10 Hz BW, analog output) Sensing element controlled over damped frequency response (-3dB 18Hz) Robust design, high shock durability (20000g) Excellent stability over temperature and time Common mode error and noise reduction using the differential measurement principle Single +5 V supply Ratiometric analog voltage outputs Digital SPI inclination and temperature output Comprehensive failure detection features o True self test by deflecting the sensing elements’ proof mass by electrostatic force. o Continuous sensing element interconnection failure check. o Continuous memory parity check.  RoHS compliant  Compatible with Pb-free reflow solder process Applications     Platform leveling and stabilization Rotating laser levels Leveling instruments Construction levels 12 VDD Sensing element 1 Signal conditioning and filtering 11 OUT_1 A/D conversion 10 ST_1 9 ST_2 Self test 1 Self test 2 EEPROM calibration memory Temperature Sensor 1 SCK SPI interface 3 MISO 4 MOSI 7 CSB Sensing element 2 Signal conditioning and filtering 5 OUT_2 6 GND Figure 1. Murata Electronics Oy www.muratamems.fi Functional block diagram Subject to changes Doc.Nr. 8261700 1/17 Rev.A3 SCA103T Series TABLE OF CONTENTS The SCA103T Differential Inclinometer Series .......................................................................1 Features............................................................................................................................................. 1 Applications ...................................................................................................................................... 1 Table of Contents......................................................................................................................2 1 Electrical Specifications .....................................................................................................3 1.1 Absolute Maximum Ratings ................................................................................................... 3 1.2 Performance Characteristics.................................................................................................. 3 1.3 Electrical Characteristics ....................................................................................................... 4 1.4 SPI Interface DC Characteristics............................................................................................ 4 1.5 SPI Interface AC Characteristics............................................................................................ 4 1.6 SPI Interface Timing Specifications ....................................................................................... 5 1.7 Electrical Connection.............................................................................................................. 6 1.8 Typical Performance Characteristics .................................................................................... 6 1.8.1 Additional External Compensation ...................................................................................... 7 2 Functional Description .......................................................................................................8 2.1 Differential Measurement ....................................................................................................... 8 2.2 Voltage to Angle Conversion ................................................................................................. 9 2.3 Ratiometric Output ................................................................................................................ 10 2.4 SPI Serial Interface................................................................................................................ 10 2.5 Digital Output to Angle Conversion ..................................................................................... 12 2.6 Self Test and Failure Detection Modes ................................................................................ 13 2.7 Temperature Measurement .................................................................................................. 14 3 Application Information ....................................................................................................15 3.1 Recommended Circuit Diagrams and Printed Circuit Board Layouts ............................... 15 3.2 Recommended Printed Circuit Board Footprint ................................................................. 16 4 Mechanical Specifications and Reflow Soldering ..........................................................16 4.1 Mechanical Specifications (Reference only) ....................................................................... 16 4.2 Reflow Soldering ................................................................................................................... 17 Murata Electronics Oy www.muratamems.fi Subject to changes Doc.Nr. 8261700 2/17 Rev.A3 SCA103T Series 1 Electrical Specifications The SCA103T product family consists of two versions, the SCA103T-D04 and the SCA103T-D05, that differ in measurement range. The specific performance specifications related to each version are listed in the table “SCA103T performance characteristics” below. All other specifications are common to both versions. The supply voltage is Vdd=5.00V and ambient temperature unless otherwise specified. Parameters marked as D are valid when measured in differential mode using an external differential amplifier. Parameters marked with S are for a single measurement channel. The performance of the selected amplifier may have an effect on some parameters. The differential signal is determined as Out_diff = Out1 – Out2. 1.1 Absolute Maximum Ratings Supply voltage (VDD) Voltage at input / output pins Storage temperature Operating temperature Mechanical shock 1.2 -0.3 V to +5.5V -0.3V to (VDD + 0.3V) -55°C to +125°C -40°C to +125°C Drop from 1 meter onto a concrete surface (20000g). Powered or non-powered Performance Characteristics Parameter D/S Condition Measuring range D Nominal Frequency response Offset (Output at 0g) Offset calibration error Offset Digital Output Sensitivity S S S S D –3dB LP Ratiometric output (1 between 0…1° Sensitivity calibration error Sensitivity Digital Output Offset temperature dependency S D D Sensitivity temperature dependency D Typical non-linearity Digital output resolution D D (2 -25…85°C (typical) -40…125°C (max) -25...85°C (typical) -40…125°C (max) Measuring range (2 Output noise density D between 0…1° From DC...100Hz Analog output resolution Cross-axis sensitivity Ratiometric error D S S Bandwidth 10 Hz Max. Vdd = 4.75...5.25V Note 1. Note 2. Note 3. Murata Electronics Oy www.muratamems.fi (3 SCA103T -D04 ±15 ±0.26 8-28 Vdd/2 ±0.057 1024 16 280 ±0.5 6554 ±0.002 ±0.29 ±0.013 -2.5...+1 ±0.057 12 0.009 0.0004 SCA103T -D05 ±30 ±0.5 8-28 Vdd/2 ±0.11 1024 8 140 ±0.5 3277 ±0.002 ±0.29 ±0.013 -2.5...+1 ±0.11 12 0.017 0.0004 Units  / Hz 0.0013 4 ±1 0.0013 4 ±1 ° % % ° g Hz V ° LSB V/g mV/° % LSB / g °/°C ° %/°C % ° Bits ° / LSB The frequency response is determined by the sensing element’s internal gas damping. The angle output has SIN curve relationship to voltage output - refer to chapter 2.2 Resolution = Noise density * √(bandwidth) Subject to changes Doc.Nr. 8261700 3/17 Rev.A3 SCA103T Series 1.3 Electrical Characteristics Parameter Supply voltage Vdd Current consumption Operating temperature Analog resistive output load Analog capacitive output load Start-up delay 1.4 Min. Typ Max. Units 4.75 5.0 4 5.25 5 V mA +125 °C Vdd = 5 V; No load -40 Vout to Vdd or GND 10 kOhm Vout to Vdd or GND 20 nF Reset and parity check 10 ms SPI Interface DC Characteristics Parameter Conditions Symbol Min Typ Max VIN = 0 V IPU VIH VIL VHYST CIN 13 4 -0.3 22 35 Vdd+0.3 1 A V V V pF Input terminal MOSI, SCK Pull down current VIN = 5 V Input high voltage Input low voltage Hysteresis IPD VIH VIL VHYST 9 4 -0.3 29 Vdd+0.3 1 0.23*Vdd A V V V Input capacitance CIN 2 pF Output terminal MISO Output high voltage I > -1mA VOH Output low voltage Tristate leakage VOL ILEAK Input terminal CSB Pull up current Input high voltage Input low voltage Hysteresis Input capacitance 1.5 Condition I < 1 mA 0 < VMISO < Vdd 0.23*Vdd 2 17 Vdd0.5 Unit V 5 0.5 100 V pA SPI Interface AC Characteristics Parameter Condition Output load SPI clock frequency Internal A/D conversion time Data transfer time @500kHz Murata Electronics Oy www.muratamems.fi @500kHz Subject to changes Doc.Nr. 8261700 Min. Typ. 150 38 Max. Units 1 500 nF kHz s s 4/17 Rev.A3 SCA103T Series 1.6 SPI Interface Timing Specifications Parameter Terminal CSB, SCK Time from CSB (10%) to SCK (90%) Time from SCK (10%) to CSB (90%) Terminal SCK SCK low time Conditions Symbol Min. TLS1 120 ns TLS2 120 ns TCL 1 s TCH 1 s TSET 30 ns THOL 30 ns Load capacitance at MISO < 15 pF Load capacitance at MISO < 15 pF TVAL1 10 100 ns TLZ 10 100 ns Load capacitance at MISO < 15 pF TVAL2 100 ns Load capacitance at MISO < 2 nF Load capacitance at MISO < 2 nF SCK high time Terminal MOSI, SCK Time from changing MOSI (10%, 90%) to SCK (90%). Data setup time Time from SCK (90%) to changing MOSI (10%,90%). Data hold time Terminal MISO, CSB Time from CSB (10%) to stable MISO (10%, 90%). Time from CSB (90%) to high impedance state of MISO. Terminal MISO, SCK Time from SCK (10%) to stable MISO (10%, 90%). Typ. Max. Unit Terminal CSB Time between SPI cycles, CSB at high level (90%) When using SPI commands RDAX, RDAY, RWTR: Time between SPI cycles, CSB at high level (90%) TLS1 TCH TLH 15 s TLH 150 s TCL TLS2 TLH CSB SCK THOL MOSI TVAL1 MISO Figure 2. Murata Electronics Oy www.muratamems.fi TSET MSB in DATA in LSB in TVAL2 MSB out TLZ DATA out LSB out Timing diagram for SPI communication Subject to changes Doc.Nr. 8261700 5/17 Rev.A3 SCA103T Series 1.7 Electrical Connection If the SPI interface is not used SCK (pin1), MISO (pin3), MOSI (pin4) and CSB (pin7) must be left floating. Self-test can be activated applying logic “1” (positive supply voltage level) to ST_1 or ST_2 pins (pins 10 or 9). Self-test must not be activated for both channels at the same time. If the ST feature is not used, pins 9 and 10 must be left floating or connected to GND. Inclination signals are provided from pins OUT_1 and OUT_2. SCK SCK 1 VDD 12 VDD OUT_1 11 OUT_1 Ext_C_1 2 Figure 3. No. 1 2 3 4 5 6 7 8 9 10 11 12 1.8 MISO 3 MISO 10 ST_1/Test_in ST_1 MOSI 4 MOSI 9 ST_2 ST_2 OUT_2 5 OUT_2 8 Ext_C_2 VSS 6 GND 7 CSB CSB SCA103T electrical connection Node SCK NC MISO MOSI Out_2 GND CSB NC ST_2 ST_1 Out_1 VDD I/O Input Input Output Input Output Supply Input Input Input Input Output Supply Description Serial clock No connect, left floating Master in slave out; data output Master out slave in; data input Output 2 (Ch 2) Ground Chip select (active low) No connect, left floating Self test input for Ch 2 Self test input for Ch 1 Output 1(Ch 1) Positive supply voltage (+5V DC) Typical Performance Characteristics Typical offset and sensitivity temperature dependencies of SCA103T are presented in following diagrams. These results represent the typical performance of SCA103T components. The mean value and 3 sigma limits (mean ± 3 standard deviation) and specification limits are presented in following diagrams. The 3 sigma limits represents 99.73% of the SCA103T population. Murata Electronics Oy www.muratamems.fi Subject to changes Doc.Nr. 8261700 6/17 Rev.A3 SCA103T Series temperature dependency of SCA103T offset (differential output) 0.3 specification limit Differential offset error [degrees] 0.2 0.1 average 0 +3 Sigma -3 Sigma -0.1 -0.2 -0.3 -40 specification limit -20 0 20 40 60 80 100 120 Tem p [°C] Figure 4. Typical temperature dependency of SCA103T offset Tem perature dependency of SCA103T sensitivity [%] (differential output) 1.5 Differential sensitivity error [%] 1 0.5 specification limit 0 average -0.5 +3 Sigma -1 -3 Sigma -1.5 -2 -2.5 -3 -40 specification limit -20 0 20 40 60 80 100 120 Tem p [°C] Figure 5. 1.8.1 Typical temperature dependency of SCA103T sensitivity Additional External Compensation To achieve the best possible accuracy, the temperature measurement information and typical temperature dependency curve can be used for SCA103T sensitivity temperature dependency compensation. The offset temperature dependency curves do not have any significant tendency so there is no need for any additional external compensation for offset. By using an additional 3rd order polynome compensation curve based on average sensitivity temperature dependency curve and temperature measurement information, it is possible to reduce sensitivity temperature dependency from 0.013%/°C down to 0.005%/°C. rd The equation for the fitted 3 order polynome curve is: Scorr  0.0000005 *T 3  0.00005 *T 2  0.0032 *T  0.031 Where: Scorr: T Murata Electronics Oy www.muratamems.fi rd 3 order polynome fitted to average sensitivity temperature dependency curve temperature in °C (Refer to paragraph 2.7- Temperature Measurement) Subject to changes Doc.Nr. 8261700 7/17 Rev.A3 SCA103T Series The calculated compensation curve can be used to compensate for the temperature dependency of the SCA103T sensitivity by using following equation: SENScomp  SENS * (1  Scorr / 100) Where: SENScomp SENS temperature compensated sensitivity Nominal sensitivity (16V/g SCA103T-D04, 8V/g SCA103T-D05) The typical sensitivity temperature dependency after 3rd order compensation is shown in the figure below. The temperature dependency of 3rd order compensated SCA103T sensitivity [%] (differential output) 1 0.8 Differential sensitivity error [%] 0.6 0.4 compensated average +3 Sigma limit 0.2 0 -3 Sigma limit -0.2 -0.4 -0.6 -0.8 -1 -40 -20 0 20 40 60 80 Tem p [°C] Figure 6. 2 2.1 rd The temperature dependency of 3 order compensated SCA103T sensitivity Functional Description Differential Measurement The measuring axis of SCA103T sensing elements are mutually opposite in direction, thus providing two inclination signals which can be differentiated externally, either by using a differential amplifier or a microcontroller. The differential measurement principle removes all common mode measurement errors. Most of the error sources have similar effects on both sensing elements. These errors are removed from measurement result during signal differentiation. The differential measurement principle gives very efficient noise reduction, improved long term stability and extremely low temperature dependency. Murata Electronics Oy www.muratamems.fi Subject to changes Doc.Nr. 8261700 8/17 Rev.A3 SCA103T Series Typical output characteristics (Channels 1, 2 and differential output: OUT1-OUT2) are presented in the figure below. For differential amplifier connection refer to the recommended circuit diagram. SCA103T-D04 outputs and differential amplifier output 6.0 5.0 4.0 3.0 Output [V] 2.0 SCA103T OUT_1 1.0 SCA103T OUT_2 0.0 Differential output -1.0 -2.0 -3.0 -4.0 -5.0 -6.0 -20 -15 -10 -5 Figure 7. 2.2 0 5 10 15 20 Tilt angle [ ° ] 2 Differential output characteristics Voltage to Angle Conversion 1 The analog output behavior of the SCA103T is described in the figure below. The arrow represents the measuring axis direction marking on the top of SCA103T package. D Earth's gravity OUT1 < OUT2 > DIFF < OUT1 =2.5V OUT2 =2.5V DIFF =0 V Figure 8. < OUT1 > OUT2