Misc power circuit diagrams

Soft Start PSU

Two soft start power supplies. The output voltage slowly increases to the desired output.

Adjustable Constant Current Load

An adjustable power load is a piece of test equipment that often comes handy in the development of certain electronics projects. For example, when you are building a power supply, it will come a time when you need to "simulate" a load to see how well your design performs as the load varies. Adding power resistors to the output can sometimes do in a pinch, but often you will not have the right resistor value handy with the right power rating for the test. This is where an adjustable electronic load comes handy. In this article, I'll show how you can build one using common components available to the electronics hobbyist.

Power Fail Alert

In this circuit an electricity supply (domestic or industrial) is continually monitored. Should the supply be interrupted then an alarm will sound for the duration of the interruption. It has battery backup and overcharge protection.

230Vac Lamp Toggle Switch

Compact, transformerless circuitry. No relays employed