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Full Wave Bridge Rectifier

A Simple 4A Full Wave Bridge Rectifier

January, 2012

This PCB design is of a fused, full-wave bridge rectifier. It is useful for projects which will run off of typical household line voltages (e.g. 230V/115V-AC). It is a very simple PCB design that requires only 4 components; a diode bridge, 2 capacitors and a fuse.
Keeping a few of these built-up in the lab keeps me from having to breadboard or wire-wrap them up when needed. They are super cheap and easy to build. Whip one up and slap it in.

The specs are largely dicated by the rectifier you choose. In this case I am using a Vishay GBL005 Glass Passivated Single-Phase Bridge Rectifier.

Absolute Maximum Ratings (TA = 25 ºC)

VRRM = 50V

VRMS = 35V

VDC = 50V

IF = 3A (PCB only), 4A with heatsink.

Typically I use them with a Radio Shack 12.6V CT 3.0A Chassis-Mount Transformer Part #273-1511. This transformer is able to convert 115VAC on it's primary to 12.6VRMS. With this transformer the two yellow leads are the secondary windings providing 12.6VRMS. I just cap off the black center tap wire. This gives me about 17.3 VDC on the rectifier's output.

Remember that the secondary voltage on the transformer is a nominal 12.6VRMS. I haveactually measured this to be about 14.8 VRMS which gives 20.9 VPP (VRMS x 1.414). A voltage drop of 2 diodes (VF = 1 V) yields 18.9 VPP, with some capcitor smoothing of the remaining 1.5V, pretty close to the 17.3 VDC measured.

Keep in mind that this is NOT a regulated DC output. It is only full-wave rectified, meaning it is not smooth. I use these where I might later replace it with a battery or other DC power source where the intent is to feed it into some sort of linear or switch-mode regulator.

You can put any size fuse you like (up to a max of 4A) in the holder, but I typically use a 3A fuse such as the Radio Shack 270-1009 3-amp 250V ACG Glass Fuse. If you plan on drawing more than 3A continuous you'll need to consider a suitable heatsink.

Here is an example power supply I built using the PCB bridge.

The BOM (Bill of Materials) for the PCB can be found here at Mouser

Eagle Schematics and Board Files (v6.1.0) can be found here.

You can also order your own PCB direct from BatchPCB by using this link here.

Kevin Fodor,
Mar 2, 2012, 4:53 AM