Bridge square-wave generator

A new circuit is proposed which uses a bridge network for the timing element. The square-wave generator consists of an RC bridge network, a voltage comparator and a pair of electronic switches. The circuit analysis in the paper shows that the generator is self compensating with respect to power-supply variations and to variations in the active circuit components. The frequency stability therefore depends almost entirely on the stability of the passive components in the RC bridge network, and a stability of 10¿3 is readily obtained over a wide range of frequencies. The circuit proposed is very suitable for practical application, particularly at low and very low frequencies. Measurements taken on an actual bridge square-wave generator are in good agreement with the results of the circuit analysis.