175 Silicon-Based Hybrid Charge Amplifier for 175 and 100-mV/G Miniature Piezoelectric Accelerometer

High-temperature hybrid miniature silicon-based charge amplifier has been designed, fabricated, and tested. The charge gain G_qap30 mV/pCplusmn1 dB at the reference frequency of 100 Hz. Frequency response deviation is plusmn1 dB at frequency range from about 0.5 Hz to about 10 kHz over the temperature range from -55degC to 175degC. The maximum change in gain is plusmn5% over that temperature range. The maximum output signal is 5 V peak at voltage supply of +24 V. The charge amplifier compromises standard components, and it is built on the ceramic disk substrate with a diameter of about 8 mm. This circuit made possible the development of the industry´s first 100-mV/G miniature (cube with side of 14 mm), lightweight (12.5 g), low-cost, and low-noise piezoelectric triaxial accelerometer with integral silicon-based electronics having operating temperature from -55degC to 175degC. In the long-term active (with power supply) test, the circuit and the accelerometer operated at temperature of 175 degC for 1000 h without any signs of degradation