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How to lower wall outlet power? Answered

I need a circuit to change the AC 240v (UK) into 5v 1A,
What is the SMALLEST possible way to do this.
I know I could use an adaptor but it there a smaller circuit that could be done?


buy a usb phone charger and open that up for the output wires


The SMALLEST methods aren't open to an amateur. They involve very detailed circuit design.

There are literally hundreds of schematics on the net to show you how to build your own 'adapter', even ones without the big step-down transformers (use great caution with these). All things considered, your best option is the store bought adaptor. 1: It is probably in its most compact form. 2: It can be taken out of the case and placed inside a wall receptacle box for more permanent use, using a small DC receptacle to plug into the wall. It is advised to place the adapter circuit on a switch.


The commercial options will be as small as possible to keep material costs as low as possible.

Browse the cheap ones, some are almost as small as an ordinary plug.