This is the simple version of a white LED lamp that can be directly powered from mains. It can give ample light even for reading purpose. Capacitor Cx along with diodes D1 through D4 forms the AC step ...

This circuit, designed on request, has proven to be useful to indicate when the voltage in a power supply line is changing from 120V to 240Vac. It can be used in different circumstances and circuits, ...

Lighting a string of LEDs at a constant brightness requires driving it with a regulated current. A boost converter is commonly used to step up the voltage to a level high enough to bias the LEDs on ...

This file type includes high-resolution graphics and schematics when applicable. For applications such as motor control or power supplies, it’s often necessary to know whether the ac line is at 120 V ...