PDM Pulse Generator

This pulse generator, which offers a mark-space ratio that is adjustable in exponentially increasing steps, is a novel use for a familiar IC. It can come in handy in a range of situations: for example, when testing the dynamic regulation characteristics of a power supply. In this test a load is applied to a power supply that draws a square-wave, rather than constant, current. An oscilloscope can then be used to check how quickly the regulator in the power supply responds and to observe any undesirable artefacts in the output such as overshoots or oscillation.