Model 3022 • Vibration/Shock Monitoring PC Board Mountable Accelerometer • Modal Analysis Millivolt Output • Motion Control Low Cost • Crash Testing • Aerospace DESCRIPTION Accelerometers FEATURES • Designed for Adhesive Mounting • ±0.5% Non-linearity (typical) • ±1.0% Temperature Performance (with comp resistors-typical) • DC Response • Built-in Damping • Built-in Over-range Stops • Low Power • Pins or No Pins The Model 3022 is a piezoresistive silicon accelerometer. The package is a ceramic substrate with a sealed ceramic cover. The ceramic provides an excellent bonding surface for the customers application specific adhesive. Each accelerometer includes a detailed calibration sheet, which provides test data and resistor compensation values for each sensor. The accelerometer consists of a micro machined silicon mass suspended by multiple beams from a silicon frame. Piezoresistors located in the beams change their resistance as the motion of the suspended mass changes the strain in the beams. Silicon caps on the top and bottom of the device are added to provide over-range stops. This design provides for a very low profile, high shock resistance, durability and built-in damping over a wide usable bandwidth. Each sensor is individually serialized. For an accelerometer with a mounting bracket designed to bolt the sensor to a mounting location, see the Model 3028. Please refer to the Models 3052 and 3058 for accelerometers with integral temperature compensation. STANDARD RANGES Range g ±2 • • • • ±5 ±10 ±20 2-10 Range g ±50 • • • • ±100 ±200 ±500 I n t e r n e t : w w w. m s i u s a . c o m Te l : 1 - 7 5 7 - 7 6 6 - 1 5 0 0 N o r t h A m e r i c a To l l F r e e : 1 - 8 0 0 - 7 4 5 - 8 0 0 8 Fax: 1-757-766-4297 Accelerometer Selection Guide–Unamplified PC Board Mountable Accelerometer Model 3022 CALIBRATION DATA Figure 1. Calibration Data Sheet A calibration data sheet similar to the sample shown above is included with each unit. The calibration sheet provides the measured test and calibration data for the sensor. In addition to the test data, the values of calibration and temperature compensation resistors are also included. Accelerometers SIGNAL CONDITIONING Figure 2. Typical Temperature Compensation and Amplification Circuit (component values specified for each sensor) Q1: 2N3904 CR1: 1N914 or equivalent Op Amps: LT1014, LM324 or equivalent • Rstc sets the excitation voltage ramp to compensate the sensitivity error due to temperature. • Rset sets the excitation voltage to 5V at 25°C. • Rzb1, Rzb2 and Rztc1 and Rztc2 calibrate the zero offset and compensate the offset error due to temperature. • Rs calibrates the output span. • Vcc must be >8 VDC. Dec 2002 Accelerometer Selection Guide–Unamplified 2-11 PC Board Mountable Accelerometer Model 3022 PERFORMANCE SPECIFICATIONS Supply Voltage: 5.0 VDC Ambient Temperature: 25°C (Unless otherwise specified) RANGE ______________________________________________________________ PARAMETERS ±2G ±5G ±10G ±20G UNITS NOTES __________________________________________________________________________________________________________________________________________________ Frequency Response [MIN] 0-250 0-300 0-400 0-600 Hz 1, 9 __________________________________________________________________________________________________________________________________________________ Mounted Resonant Frequency [MIN] 700 800 1000 1500 Hz 8, 9 __________________________________________________________________________________________________________________________________________________ Sensitivity (MIN/MAX) 8.0/20.0 6.0/15.0 3.0/6.0 1.5/3.0 mV/g 2 RANGE ______________________________________________________________ PARAMETERS ±50G ±100G ±200G ±500G UNITS NOTES __________________________________________________________________________________________________________________________________________________ Frequency Response [MIN] 0-1000 0-1500 0-2000 0-2400 Hz 1, 9 __________________________________________________________________________________________________________________________________________________ Mounted Resonant Frequency [MIN] 2000 3000 4000 5000 Hz 8, 9 __________________________________________________________________________________________________________________________________________________ Sensitivity (MIN/MAX) 0.6/1.5 0.3/0.6 0.15/0.3 0.06/0.15 mV/g 2 PARAMETERS MIN TYP MAX UNITS NOTES __________________________________________________________________________________________________________________________________________________ Zero Acceleration Output 5.0 25.0 ±mV 9 __________________________________________________________________________________________________________________________________________________ Damping Ratio 0.4 0.7 0.9 8, 9 __________________________________________________________________________________________________________________________________________________ Non-linearity 0.5 1.0 ±% Span 4 __________________________________________________________________________________________________________________________________________________ Transverse Sensitivity 1.0 3.0 ±% Span __________________________________________________________________________________________________________________________________________________ Input & Output Resistance 2.5 3.5 6.5 kΩ 9 __________________________________________________________________________________________________________________________________________________ Temperature Error - Span 1.0 2.0 ±% Span 3, 5 __________________________________________________________________________________________________________________________________________________ Temperature Error - Zero 1.0 2.0 ±% Span 3, 5 __________________________________________________________________________________________________________________________________________________ Supply Voltage 5.0 10.0 VDC __________________________________________________________________________________________________________________________________________________ Output Noise 1.0 µV p-p 6 __________________________________________________________________________________________________________________________________________________ Output Load Resistance 5 MΩ __________________________________________________________________________________________________________________________________________________ Acceleration Limits (Any Direction) 20X Rated 7 __________________________________________________________________________________________________________________________________________________ Operating Temperature -40°C to +125°C __________________________________________________________________________________________________________________________________________________ Accelerometers Storage Temperature -55°C to +150°C __________________________________________________________________________________________________________________________________________________ Weight 6.5 Grams __________________________________________________________________________________________________________________________________________________ Materials Alumina ceramic substrate with alumina ceramic cap Notes 1. The frequency response is defined as the range of frequencies over which the device sensitivity is within ±5% of the DC value. 2. Output voltage increases for positive acceleration; output voltage decreases for negative acceleration. 3. Percentage values are with external compensation. The uncompensated temperature coefficients are measured and specified with each unit. In addition, the values of the resistors that provide a temperature compensated output are provided with each unit. These resistors are for use in the circuit shown in Figure 2. 4. Best Fit Straight Line. For full scale ranges of 10g or less, the maximum non-linearity is ±2%. 5. Compensated temperature range: 0-50°C in reference to 25°C. 6. 10 Hz to 1 kHz. 7. 400g for ±2g, ±5g, and ±10g versions. 20X or 2000g for other versions, whichever is less. 8. For sensors having a resonant frequency greater than 5 kHz, the calibration data sheet will indicate ">5 kHz." In addition, the damping ratio will indicate N/A. 9. Actual test data for this parameter is included on the calibration sheet provided with each sensor. A sample of this calibration sheet is shown as Figure 1. I n t e r n e t : w w w. m s i u s a . c o m Te l : 1 - 7 5 7 - 7 6 6 - 1 5 0 0 N o r t h A m e r i c a To l l F r e e : 1 - 8 0 0 - 7 4 5 - 8 0 0 8 Fax: 1-757-766-4297 2-12 Accelerometer Selection Guide–Unamplified PC Board Mountable Accelerometer Model 3022 LTR 2 - 10 g 20 - 500 g “A” DIM 0.300 ± 0.005 0.265 ± 0.005 [7.62 ± 0.13] [6.73 ± 0.13] “B” DIM 0.250 ± 0.005 0.240 ± 0.005 [6.35 ± 0.13] [6.10 ± 0.13] 0.032 ± 0.004 0.032 ± 0.004 [0.81 ± 0.10] [0.81 ± 0.10] “C” DIM Accelerometers DIMENSIONS CONNECTIONS ORDERING INFORMATION Dec 2002 Accelerometer Selection Guide–Unamplified 2-13