Pulse generator having variable pulse occurrence rate

摘要

A pulse generator circuit provides output pulses that vary in frequency in accordance with a digital input word. An external source frequency produces a predetermined number of pulses over a fixed time interval with the pulse generator circuit selecting the desired number of pulses from those in this interval to provide at its output. Any number of the pulses between zero and the total number in the interval may be selected. To assure their distribution over the interval, the pulses are arranged to occur in sets with the pulses of a given set occurring in the middle of the pulses of another set in order to prevent the bunching of selected pulses into any part of the interval. The sum of the pulses in the combined sets then provides in accordance with the digital input word the desired frequency which ranges up to and includes the source frequency.