High-Temperature, Up to 175 °C, Miniature IEPE Accelerometers

Abstract

This chapter describes the recently designed high temperature, up to 175 °C, IEPE miniature, light-weight accelerometers: three families of triaxial accelerometers and one family of the single axis accelerometers. This temperature is near the industry’s highest operating temperature among IEPE miniature accelerometers. In addition to the high temperature operation and miniature design, the sensors feature wide frequency range, low noise, and some of them include the 2-pole active low-pass filter (LPF).The triaxial accelerometers of one family have a cube shape with a side of 14.8 mm and a weight of 14 g and feature sensitivities of 100 and 10 mV/g. The other group of triaxial accelerometers has the same cube shape, but with a side of 10 mm, weight of 5 g, and sensitivities 10, 1, and 0.5 mV/g. The triaxial sensors of the third group have the same shape, dimensions, and weight of the previous sensor family, sensitivity of 10 mV/g, and, additionally, they incorporate the 2-pole active LPF. The single axis accelerometer has size 8.1 × 6.6 × 6.4 mm³, weight of 1 g, sensitivity of 10 and 100 mV/g, and also comprise the 2-pole active LPF. This LPF is used for suppression of the PE transducer’s resonance and for attenuation of the high frequency vibration signals that can cause saturation of electronics. The sensors contain miniature high-temperature hybrid silicon-based charge and voltage amplifiers. In the long-term active (with power supply on) test, the sensors operated at a temperature of 175 °C for more than 1,000 h without any signs of degradation.