János Nagy

A previous Design Idea describes a programmable current source that used a three-terminal LM317 adjustable regulator (Reference 1). Although that circuit lets you program the output current, the load current flowed through the BCD (binary-coded-decimal) switches. However,...

In 1971, Signetics – later Philips – introduced the NE555 timer, and manufacturers are still producing more than 1 billion of them a year. By adding a few components to the NE555, you can build a simple voltage-to-frequency converter for less than 50 cents. The...