A Voltage-Controlled Free-Running Multivibrator Using a Pair of Regenerative Switches

A voltage-controlled free-running multivibrator is described. In the new circuit use is made of two bistable regenerative switches connected by a single timing capacitor to realize an astable multivibrator. The circuit provides rectangular output waveforms of very short rise and fall times over a wide range. Low output impedance of the regenerative switches permits driving large resistive and capacitive loads. Among other features of the circuit are the facility of logarithmic or linear variations of frequency by a modulating control voltage, its sure-starting nature, and its integrability.