RADIATION MEASUREMENT SYSTEM WITH MOSFET ELECTROMETER CIRCUIT WHICH IS PROTECTED AGAINST VOLTAGE TRANSIENTS

摘要

A radiation measurement system includes an electrometer circuit employing a metal-oxide-semiconductor device as an active element for amplifying a minute d.c. input signal from a radiation detector to provide an appreciable signal output voltage. The electrometer comprises means for preventing undesired voltage transients which may be applied with the input signal from puncturing the metal-oxide-semiconductor device, without impairing its ability to amplify the minute d.c. input signal.