2264-005

SILICON DESIGNS, INC P-CapTM Model 2264 ANALOG ACCELEROMETER MODULE ! Accurate, Easy-to-Use Alternative to Piezoresistive Accelerometers ! Sensitivity Insensitive to Variations in Excitation Voltage, Temperature and Cable Resistance ! Frequency Response Insensitive to Temperature ! 6 to 22V Excitation (dual or single supply) ! Differential Output Signal / EMI Resistant ! Capacitive Micromachined ! Nitrogen Damped to 0.7 (nominal) ! Sensitivity Accurate to 2% (typical) ! -40 to +85EC Operation ! Traditional Four Wire Connection ! Responds to DC and AC Accelerations ! Rugged Anodized Aluminum Module & PTFE Cable ! Serialized for Traceability ! Non-Standard g Ranges Available ! Other Output Sensitivities Available ORDERING INFORMATION Full Scale Acceleration ± 5g ± 10 g ± 25 g ± 50 g ±100 g ±200 g Model Number 2264-005 2264-010 2264-025 2264-050 2264-100 2264-200 DESCRIPTION The P-CapTM model 2264 accelerometer is a high performance and wide temperature range accelerometer intended to directly replace piezoresistive units for existing and new applications. It uses a capacitive sensing element and an advanced ASIC to simulate the operation of a piezoresistive bridge. It is tailored for zero to medium frequency instrumentation applications. The anodized aluminum case is epoxy sealed and is easily mounted via two #4 (or M3) screws. Internal regulation is provided to eliminate the effects of excitation voltage variation. Unlike piezoresistive elements, its sensitivity, bias and frequency response are insensitive to temperature changes or thermal gradients. The cable’s shield is electrically connected to the case while the ground (GND) wire is isolated from the case. An optional initial calibration sheet (2264-CAL) and periodic calibration checking are also available. OPERATION The P-CapTM model 2264 can be operated from supply voltages ranging from ±3 to ±11 VDC. It produces two analog voltage outputs which vary with acceleration as shown in the graph on the next page. The sensitive axis is perpendicular to the bottom of the package, with positive acceleration resulting from a force pushing on the bottom of the package. The signal outputs are fully differential about a common mode voltage that is midway between the two supply voltages which is 0 volts when equal plus and minus supplies are used. The output sensitivity or scale factor is independent of changes in the excitation voltage. At zero acceleration, the output differential voltage is nominally 0 volts DC; at ±full scale acceleration the output differential voltage is ±0.5 volts DC respectively. Single supply operation is also possible by connecting -Exc to ground and +Exc to +6 to +22 VDC but the average value of the +OUT and -OUT signals will be at ½ the supply voltage and each output will swing from ±0.25 volts around the ½ supply voltage level. Standard cable length is 1 meter. APPLICATIONS ! CRASH TESTING ! VIBRATION MONITORING ! VIBRATION ANALYSIS ! MACHINE CONTROL P-Cap is a trademark of Silicon Designs, Inc. ! MODAL ANALYSIS ! ROBOTICS ! FLIGHT TESTING ! MACHINERY INSTRUMENTATION Silicon Designs, Inc. ! 1445-NW Mall Street, Issaquah, WA 98027-5344 ! Phone: 425-391-8329 ! Fax: 425-391-0446 web site: www.silicondesigns.com [page 1] Apr 07 P-CapTM Model 2264 Analog Accelerometer Module SIGNAL DESCRIPTIONS (28 gauge wires + shield) Power: +Exc (Red) and -Exc (Black): +Exc (+3 to +11 VDC) and -Exc (-3 to -11 VDC). +Out (Green) and -Out (White): +Out minus -Out voltage is proportional to acceleration; +Out voltage increases and -Out decreases with positive acceleration. At zero acceleration both outputs are nominally equal to mid-way between the +Exc and the -Exc values. The device experiences positive (+1g) acceleration with its lid (part number) facing up in the Earth’s gravitational field. Either output can be used individually or the two outputs can be used differentially. (See output response plot below) PERFORMANCE - By Model: +Exc=+5, -Exc=-5VDC, TC=25EC MODEL NUMBER Input Range Frequency Response (Nominal, -3 dB) Sensitivity, Differential Output Noise, Differential (RMS, typical) Max. Mechanical Shock (0.1 ms) 2264-005 ±5 0 - 600 100 9 2264-010 ±10 0 - 1000 50 10 2264-025 ±25 0 - 1500 20 25 2264-050 ±50 0 - 2000 10 50 2264-100 ±100 0 - 2500 5 100 2264-200 +/-200 0 - 3000 2.5 200 UNITS g Hz mV/g µg/(root Hz) g 2000 PERFORMANCE - All Models: Unless otherwise specified, +Exc=+5, -Exc=-5VDC, TC=25EC, Differential Mode. PARAMETER Cross Axis Sensitivity Bias Calibration Error Bias Temperature Shift (TC= -40 to +80EC) Sensitivity Calibration Error 2 MIN TYP 2 50 MAX 3 5 200 5 +250 0.5 1.0 1.5 0.3 +0.25 ±11 13 624 UNITS % % of span (ppm of span)/EC % ppm/EC % of span % VDC VDC mA DC mA/volt µV/µA grams grams/meter Sensitivity Temperature Shift (TC= -40 to +80EC) -005 thru -050 -100 -200 Sensitivity Change with Excitation Voltage (6-22 volts) Small Signal Differential Output Impedance Output Common Mode Voltage 3 Operating Voltage (+Exc/-Exc) Non-Linearity 1, 2 (-90 to +90% of Full Scale) Operating Current (+Out and -Out open) Change in Operating Current to Excitation Voltage Shunt Calibration Sensitivity Mass (not including cable) Cable Mass Note 1: 100g versions and above are tested from -65g to +65g. Note 2: Tighter tolerances available upon request. SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE -250 2 0 0.15 0.25 0.40 0.1 1225 0 ±5 10 0.25 612 6 14 -0.25 ±3 600 Note 3: Voltage between +Exc and -Exc must not exceed 24V. P-cap IS A REGISTERED TRADEMARK OF SILICON DESIGNS, INC. Silicon Designs, Inc. ! 1445-NW Mall Street, Issaquah, WA 98027-5344 ! Phone: 425-391-8329 ! Fax: 425-391-0446 web site: www.silicondesigns.com [page 2] Apr 07