AUX Power - How and Why

A project log for Muffsy Hifi Dual Power Supply

...without handling mains power

skrodahlskrodahl 05/08/2015 at 07:510 Comments

This power supply will give you about 100 mA of regulated power, add heat sinks and you will double that.

Given that the regulated power is a limited resource, wouldn't it be nice to cram some extra juice out of this power supply?

Notice at the bottom right corner, there are three pads called AUX, GND and LED.

This is the auxiliary DC power.

You can use this for any additional devices that needs DC power. There is also space for a resistor, called LED.

AUX Power

For anything that needs DC power, connect AUX and GND (positive and negative connections).

Connect an LED

There is space for an on-board current limiting resistor for LEDs. Add a suitable resistor and connect your LED to the connections LED and GND.

(It is usually safe to assume that the forward voltage drop of your LED is 2 volts, and that the maximum forward current is 20 mA.)