As it turns out, the ever-useful 555 timer chip does the job admirably. It’s a simple enough circuit, the threshold pin is pulled high so the output goes high, and the PWM drive from an Arduino ...

The SX8122 comes in a SOIC eight-pin package and is available in production quantities at $0.36 each in 2,500-piece lots. An evaluation kit is available as well.

For Butterfield, you would start with 28. So, with this in mind, let's take another look at 555. Hochheiser: Now, some combinations for the first two letters of a word worked better than others.