SCA121T Series Data Sheet THE SCA121T DUAL AXIS INCLINOMETER MODULES The SCA121T Series contain 3D-MEMS-based dual axis inclinometer modules that provide instrumentation grade performance for leveling applications in harsh environment. The measuring axes of the sensing elements are parallel to the mounting plane and orthogonal to each other. Low temperature dependency, high resolution and low noise, together a with robust sensing element design, make the SCA121T the ideal choice for leveling instruments. The Murata inclinometers are insensitive to vibration, due to their over damped sensing elements, and can withstand mechanical shocks of up to 20000 g. Features Dual axis inclination measurement (X and Y) Measuring ranges 30 and 90 0.0025 resolution (10 Hz BW, analog output) Sensing element controlled over damped frequency response (-3dB 18Hz) Robust design, high shock durability (20000g) High stability over temperature and time Single +5 V supply and unregulated 7...35V supply RoHS compliant Leveling instruments Construction levels Applications Platform leveling and stabilization 360 vertical orientation measurement Murata Electronics Oy www.muratamems.fi Subject to changes Doc.Nr. 82 1274 00 1/5 Rev.A SCA121T Series TABLE OF CONTENTS The SCA121T Dual Axis Inclinometer modules .....................................................................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 Electrical Connection.............................................................................................................. 4 2 Functional Description .......................................................................................................4 2.1 Measuring Directions .............................................................................................................. 4 2.2 Voltage to Angle Conversion ................................................................................................. 4 2.3 Ratiometric Output.................................................................................................................. 5 3 Mechanical Specifications ..................................................................................................5 3.1 Sensor dimensions ................................................................................................................. 5 Murata Electronics Oy www.muratamems.fi Subject to changes Doc. nr. 82 1274 00 2/5 Rev.A SCA121T Series 1 Electrical Specifications The SCA121T product family comprises three versions, the SCA121T-D03, the SCA121T-D05 and the SCA121T-D07 that differs in measurement range and supply voltage. The product version specific performance specifications are listed in the table SCA121T performance characteristics below. 1.1 Absolute Maximum Ratings Supply voltage SCA121T-D05(VDD) Supply voltage SCA121T-D03 and D07 Voltage at input / output pins Storage temperature Operating temperature Mechanical shock 1.2 Regulated -0.3 V to +5.5V Unregulated -0.3 V to +35V -0.3V to 5.3 -55C to +125C -40C to +125C Drop from 1 meter onto a concrete surface (20000g). Powered or non-powered Performance Characteristics Parameter Condition Measuring range Nominal Supply Voltage Offset (Output at 0g) Offset calibration error Sensitivity Max deviation between 0...1 (1 Sensitivity calibration error Offset temperature dependency Typical non-linearity Frequency response -25...85C 0...70C -25...85C 0...70C Measuring range (2 -3dB LP Ratiometric error Cross-axis sensitivity Vdd = 4.75...5.25V Max. Sensitivity temperature dependency Note 1. Note 2. Murata Electronics Oy www.muratamems.fi SCA121TD03 90 1 7...35 2.5 1.5 2 35 1.5 SCA121T -D05 90 1 50.25 Vdd/2 1.5 2 35 1.5 SCA121T -D07 30 0.5 7...35 2.5 1.5 4 70 1.5 Units 1 0.5 -1.5...+0.5 -0.8...+0.3 N/A 8-28 1 0.5 -1.5...+0.5 -0.8...+0.3 N/A 8-28 1 0.5 -1.5...+0.5 -0.8...+0.3 0.57 8-28 % % Hz 4 % % 1 4 g V V V/g mV/ % The angle output has SIN curve relationship to voltage output The frequency response is determined by the sensing element's internal gas damping. Subject to changes Doc. nr. 82 1274 00 3/5 Rev.A SCA121T Series 1.3 1.4 2 2.1 Electrical Characteristics Parameter Condition Min. Current consumption Operating temperature Analog resistive output load Analog capacitive output load Start-up delay Vdd = 5 V; No load Vout to Vdd or GND Vout to Vdd or GND Reset and parity check -25 10 Typ Max. Units 5 8 +85 mA C kOhm nF ms 20 10 Electrical Connection Wire Color Name Function Blue Red Yellow Green White GND Vdd Out X Out Y NC Ground Power supply X-axis output Y-axis output Not Connected Functional Description Measuring Directions Figure 1. The measuring directions of the SCA121T 2.2 Voltage to Angle Conversion Analog output can be transferred to angle using the following equation for conversion: Vout Offset Sensitivit y arcsin Where: Offset = output of the device at 0 inclination position, Sensitivity is the sensitivity of the device and VDout is the output of the SCA121T. The nominal offset is 2.5 V and the sensitivity is 4 V/g for the SCA121T-D07 and 2 V/g for the SCA121T-D03 and SCA121T-D05. Angles close to 0 inclination can be estimated quite accurately with straight line conversion but for the best possible accuracy, arcsine conversion is recommended to be used. The following table shows the angle measurement error if straight line conversion is used. Murata Electronics Oy www.muratamems.fi Subject to changes Doc. nr. 82 1274 00 4/5 Rev.A SCA121T Series Straight line conversion equation: Vout Offset Sensitivit y Where: Sensitivity = 70mV/ with SCA121T-D07 or Sensitivity= 35mV/ with SCA121T-D03 and SCA121T-D05 Tilt angle [] 0 1 2 3 4 5 10 15 30 2.3 Straight line conversion error [] 0 0.0027 0.0058 0.0094 0.0140 0.0198 0.0787 0.2185 1.668 Ratiometric Output Ratiometric output means that the zero offset point and sensitivity of the sensor are proportional to the supply voltage. If the SCA121T-D05 supply voltage is fluctuating the SCA121T-D05 output will also vary. When the same reference voltage for both the SCA121T-D05 sensor module and the measuring part (A/D-converter) is used, the error caused by reference voltage variation is automatically compensated for. 3 Mechanical Specifications Cable length: Cable type: Cable diam.: Leads: Total weight: Protection class: Housing: Mounting: 3.1 -D03,-D07 30cm -D05 110cm UL/CSA listed, PUR black 60.2mm 2 5 x 0.14mm Approx. 60 grams IP66 Zinc casting with passivation The sensor module is to be mounted on a flat and smooth surface with 2 screws, dimension M4. Mounting torque 5 1Nm Sensor dimensions Figure 2. Murata Electronics Oy www.muratamems.fi Mechanical dimensions of the SCA121T (Dimensions in mm) Subject to changes Doc. nr. 82 1274 00 5/5 Rev.A