I have a Raspberry Pi web server(pi.melihkarakelle.com)(temporary unavailable) and I want to drive it with solar energy. The main problem is high current consumption of Raspberry Model B (330mA)
The solution is very simple. Just remove the Network/USB hub IC and solder two jumper wire(between R36 and R37) to enable one USB port without this IC.
Please read this blog first
After this hack, My Pi is working with 190mA at 5V including WiFi USB dongle . But this is not enough. The system working with 3.3v and on board linear voltage regulator dropping the 5v to 3.3v. This is compleately waste of energy. My second target is using better LDO regulator.
I replaced the original regulator with MIC2502-3.3
MIC2502 is very low drop out regulator IC and output is 3.3v when you supply it with 3.4v – 16v . If your supply drops to 3.1v, It will give already 3v output and still enough to working your Pi.
Here is the macro photo of the new regulator (you need fine soldering skill to doing that)
Now my Pi working with single cell Li-Po, Li-Ion Â or USB without any extra modification.
You can save 20mA Â by switching off the PAL/HDMI outputs. Add this command on your startup:
then my web server working with only 170mA 🙂
I will share the other stages of the project on my new posts.