Rugged, Miniature High Sensitivity Piezoresistive Transducers

Sept. 28, 2009
Endevco Corporation (Endevco®) (www.endevco.com), a Meggitt Group Company and global leader in the design and manufacture of sensing solutions for demanding vibration, shock and pressure applications, has announced the availability of the 8540 series , a family of highly rugged, miniature high sensitivity piezoresistive absolute pressure transducers.  Their excellent linearity and very high resonance, makes them ideal for measuring static or dynamic pressure within a variety of high temperature applications.Endevco 8540 series transducers employ piezoresistive MEMS technology housed in a rugged stainless steel case, for maximum sensitivity and wide frequency response, and with an industry exclusive full scale output to 300 mV. Internal sensitivity compensation and zero trim provide accuracy to +500 °F (+260 °C) with diminished lifetime operations in temperatures up to +600 °F (+316 °C). In addition, this transducer series exhibits low photo-flash sensitivity and high stability during temperature transients. Available in ranges from 15 to 500 psia, the 8540 series features a small (0.15 inch; 3.8 mm) face diameter, which facilitates flush mounting for skin pressure measurements on aircraft; inlet distortion pressures in turbine engines; or transmission pressures in automobiles. The transducer’s high frequency response enables it to be used on small wind tunnels scale models, as well as within rocket, jet engine and auxiliary power unit (APU) monitoring applications.  Transducers are supplied with integral cable. Recommended accessories for use with the Endevco 8540 series include the new model 4990a (Oasis), as well as model 136 three-channel system or model 4430A signal conditioner.  • SIGNAL INPUT - True differential input; programmable AC or DC coupling • MAXIMUM INPUT VOLTAGE ± 50V differential and ± 300 V common mode (DC or AC pk) • Input Impedance DC Coupled, 50 M?, minimum • AC Coupled, 1 M?, typical • Common Mode Rejection Ratio 120 dB minimum, DC to 60 Hz for Gain ? 100 • Common Mode Voltage 300 Vdc or AC peak maximum operating • Maximum Conductors 9 conductors for full, half or quarter bridge devices • EXTERNAL CALIBRATION The differential input can be switched to the Calibration Voltage Input • Voltage Range 0.100 to 15.000 Vdc minimum in 5 mV steps ± 5 mV accuracy • Compliance Current 100 mA minimum • Short Circuit Current Limit 130 mA typical • Voltage Noise ? 300 µV pk-pk (0.1 Hz to 20 kHz) • Remote Sense Sense current is < 0.1 mA • AMPLIFIER ZERO Performed whenever there is a change in gain, filter, or coupling change • Accuracy ? ± [1 µV RTI +1 mV RTO] • Manual Zero Resolution ±20 µV resolution RTO typical