Home

5V power buck power supply for bicycle use

February 14, 2012

It has to digest a wide range of input voltages, and it has to be efficient enough to deliver 2.5 watts of power.
This version has several flaws (spec’d wrong buck diode, holes were not large enough; needed to bias D+ and D- to make iDevices happy about charging), but with some tinkering, it works (tested with iPod Classic and Nano). Further research needed to figure out why it won’t charge my Motorola phone. Further research: mini-USB is a 5-pin connector, and pin #X (they call it that) is shorted to pin 2 and connector to pin 4 (GND) with a 200k resistor. For now, I will just buy a cable that claims to work for this purpose.

IMG_0288

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: