A HIGH-RESOLUTION AUTOGAIN RANGING LINEAR ELECTROMETER AMPLIFIER

A current electrometer, capable of operating over a wide range of temp eratures is presented. It measures bipolar currents from 3.16 pA to 50 mu A in ten sensitivity ranges on a linear scale with a current resol ution of 0.2%. The electrometer range depends upon the magnitude of th e input current. The measurement accuracy is better than +/-1% at 25 d egrees C for currents between 100 pA and 50 mu A and remains within +/ -3% in the temperature range of -15 to 55 degrees C. (C) 1996 American Institute of Physics.