Method and apparatus for processing an analog signal

Claim 1

A circuit for processing analog signals comprising generating means for generating a variable D.C. voltage and having an input connected to receive the said analog signals and an output for said variable D.C. voltage, said generating means comprising: (a) a peak voltage following arrangement including a first differential amplifier having an inverting input connected to receive the said analog signals through a first capacitor connected to said generating means input, a noninverting input connected to receive a D.C. reference voltage, and an output, a second capacitor having one of its electrodes connected to a ground potential, a diode connected between the output of said first differential amplifier and the other electrode of said second capacitor to charge the latter, and a discharge circuit for the said second capacitor which, in conjunction with said second capacitor, defines a selected time constant, and (b) an amplifier having an input connected to said other electrode of said second capacitor and an output connected to said output of said generating means, and voltage summing means having two inputs, one of which is connected to receive the said analog signals through said first capacitor and the other of which is connected to the output of said generating means, and an output for delivering a succession of steep-sided pulses responsive to analog signals applied to said circuit.