Low-noise voltage-sensitive preamplifier with output stabilization by pole-zero cancellation in the feedback circuit

Abstract

Low-noise, voltage-sensitive preamplifiers were designed with pole-zero cancellation in the feedback circuit to stabilize the output baseline against variations in the mean rate and amplitude of random signals. Compared to conventional feedback and subsequent pole-zero cancellation, this method of baseline stabilization increased the fraction of signals transmitted without distortion by preamplifier saturation from 50 to > 99% for steplike input signals of 240 m V amplitude occurring randomly at a mean rate of 10 4 signals/sec.

Recent improvements toRC-line encoded position-sensitive proportional counters

“…Pole-zero cancellation in the feedback circuit (Kopp & Williams, 1977) stabilizes the output voltage of low-noise, voltage-sensitive preamplifiers against fluctuations in ambient temperature and reduces preamplifier saturation at high count rates. Pole-zero cancellation does not affect the input noise of the preamplifier, and, in most cases, requires only an adjustment of a capacitor in the feedback circuit.…”