USB Battery Charger | Electronic Project Circuits

Posts Tagged ‘USB Battery Charger’

USB iPOD Charger by REG1117A

The circuit’s pretty simple, basicly it’s just a voltage regulator. Both the LM317 and the REG1117A (LDO) fit the PCB, maybe there are even more types that I’m aware of that can be used on it. I did add one extra thing: a LED that shows if the connected device is consuming power. To do this I used a shunt resistor and a current converter. I choose 0.2 ohm for the shunt, since it’s not hard to come by and should only drop 0.1V @ 500mA. Either an INA168 (current output) or an INA193-198 (INA194 is best in this case) (voltage output) will fit as current converter. The trip point at which the LED should start to burn can easily be adjusted by one resistor (in case of the INA168) or by two (in case of the INA193-198). In the schematic it is set at 100mA using an INA168 using a 950k resistor. The Schmit buffer is a Texas Instruments Little Logic chip (1G17).
Source:http://members.lycos.nl/anthonyvh/index.php?page=usb-charge

Be the first to comment - What do you think? Posted by admin - March 11, 2008 at 9:29 am

Categories: Battery charger Tags: ipod battery charger, LM317, USB Battery Charger

iPOD – MP3 Player Charger by MC34063

Portable iPod charger that you can use while away from your computer. The circuit is based around an MC34063 switchmode regulator. This has high efficiency so that there is very little heat produced inside the box, even when delivering its maximum output current. The circuit is more complicated than if we used a 7805 3-terminal regulator but since the input voltage could be 15V DC or more, the voltage dissipation in such a regulator could be 5W or more at 500mA. and 5W is far too much for a 7805, even with quite a large heatsink.

Read More Source:http://electronics-diy.com/electronic_schematic.php?id=139
Thank you.

Be the first to comment - What do you think? Posted by admin - January 2, 2008 at 11:18 am

Categories: Battery charger Tags: ipods, MC34063, NiMh battery charger, USB Battery Charger

USB Li-ion battery charger

This is a charger for lithium ion batteries which takes its power from the USB port of a computer. It uses the MCP73861 or MCP73863 Li-ion battery charger chip manufactured by Microchip. The circuit board is a piece of single sided copper clad board. A hole is cut inside it so that it will accommodate the integrated circuit.

The MCP73861 or MCP73863 (they are similiar, with only slight differences which do not affect the circuit connections) is available in a small leadless package.

The difficulty? There are no leads to solder to. The advantage? There are no leads to break!

Source:http://www.instructables.com/id/USB-Li-ion-battery-charger/