This article is part of the Ideas for Design Series: Vol. 3, No. 7. This simple, robust, and low-cost signal generator, based on the LM386 power amplifier IC, provides a trio of audio-band signals ...

Here is a simple frequency doubler circuit that produces a square wave output with a precise 50 percent duty cycle. There are similar circuits in the literature [References 1, 2, 3] which require ...