The circuits presented here use ananalog switch—such as a DG419or one-third of a CD4053—to combinean analog signal with a standard PWMsignal. Most microcontrollers can easilygenerate the PWM signal.

This article was originally published by computer historian Ken Shirriff on his blog. Thanks to his kind permission, the article is reproduced here. Eine Übertragung ins Deutsche ist ebenfalls ...