HYBRID DC ACCURATE CHARGE AMPLIFIER FOR LINEAR PIEZOELECTRIC POSITIONING

摘要

Piezoelectric transducers are known to exhibit less hysterisis when driven with current or charge rather than voltage. Despite this advantage, such methods have found little practical application due to the poor low frequency response of present current and charge driver designs. This paper introduces a new circuit topology free from low-frequency drift and DC load offsets. The hybrid load feedback charge amplifer contains a secondary low-frequency voltage feedback loop to stabilize the low-frequency and DC operation of the amplifier.