Power a battery operated device from a USB 6V charger

Thread Starter

JackPollack

Joined Feb 29, 2016
28
I would like to power a battery operated device from a USB 6V charger.
The device uses 2 AA batteries (3V). I think I can use diodes (maybe in parallel?) to drop the voltage.
Is parallel correct? and how many diodes would I need to make the 3V drop?

Thanks
 

MrChips

Joined Oct 2, 2009
30,720
I would like to power a battery operated device from a USB 6V charger.
The device uses 2 AA batteries (3V). I think I can use diodes (maybe in parallel?) to drop the voltage.
Is parallel correct? and how many diodes would I need to make the 3V drop?

Thanks
Depends on how much current your device takes.
Start with five 1N4001 diodes and measure the voltage at the device. Go to four diodes if you need a higher voltage.
 
One comment... USB chargers aren't 6V. They are 5V. 5.5V is the absolute max you should ever see on the output of a USB charger.

The diodes in series could work but be aware that they aren't going to give a very tightly regulated voltage. The voltage will change depending on the current being drawn and this will be multiplied by the fact that they are in series.

Assuming you don't need to draw much current a 3.0V LDO might be an option worth looking at.
 
Top