Using modulated rectangular waves of different time periods, the circuit presented here produces ringing tones similar to those produced by a telephone. The circuit requires four astable ...

We must admit that we’ve been guilty of using a microcontroller to make two LEDs blink alternately in the past. It’s not the worst transgression, but it stems from our discomfort with analog circuits.

Some time ago, I reverse-engineered a low-cost inverter made by Vector Mfg. (now Black & Decker). It uses a classic 2-BJT astable multivibrator (AMV) but with a circuit design twist, as shown below.

Pondering how the three-way multivibrator worked in the way home, I decided that the base waveforms must be overlapping triangle waves – which would give a good reason for the nice 120° output ...

Fig 1. The voltage downconverter for high-power-density lithium-polymer batteries enables them to replace older battery technologies in applications that otherwise could not employ their higher ...