a mechanism to produce trains of periodic pulses having a fixed relationship break pulse

摘要

A circuit is disclosed for generating a periodic pulse train having any fixed desired duty cycle from a periodic input signal which may be either analog or digital. The input signal is fed to a transistor amplifier whose bias can be varied. The output of the transistor amplifier is coupled to an amplifying element whose possible voltage swing is limited to provide the desired pulse train. The desired pulse train from the amplifying element is coupled through a low-pass filter prior to comparison with a reference voltage in a differential amplifier. The voltage difference at the output of the differential amplifier adjusts the bias of the transistor amplifier such that the voltage of the low pass filtered desired pulse train is very close to the reference voltage.