Introduction: USB Lipo Charger
This the first test !
It's not the final version .
It's the first time i soldering smd parts.
dont worry it's very easy;
put little past soldering on the pad to the board
put the smd
solder with a little hot air gaz soldering iron or hot air station .
the past make all the job !!
This version is with load sharing
The mosfet disconnect the battery from load when the usb is connected
The load is directly powered by usp when the battery charge
http://ww1.microchip.com/downloads/en/AppNotes/01149c.pdf
Step 1: Shematic
change are :
- remap the mosfet
- remap the exit connectors
- remap the shunt
Step 2: Board
the first version : dont order it it's fail !!!
http://oshpark.com/shared_projects/QC0IcBFP
the second version
https://oshpark.com/shared_projects/JrB1LeKG
the price is 3.30 $ for 3 board
The last version i ordered
http://oshpark.com/shared_projects/15unOOQL
New version V2.0( not tested) of my lipo charger. Change the mosfet implement error. Change the shunt implement on the bottom. Add DIP switch from TE Connectivity
Step 3: BOM
C1 4.7 uF CAP0805 0805
C2 4.7 uF CAP0805 0805
C3 1 uF CAP0805 0805
D1 DIODE-SCHOTTKY_ DIODE-SCHOTTKY_ SMA-DIODE
JP1 USBPCB USBPCB USB-A-PCB USB Connectors
JP2 M02POLAR_LOCK
JP3 M02POLAR_LOCK
LED1 Charge LEDCHIPLED_0805 red
LED2 Full LEDCHIPLED_0805 green
Q1 MOSFET-PCHANNELSMD MOSFET-PCHANNELSMD SOT23-3
R1 150 RESISTOR0805-RES 0805 Resistor
R2 150 RESISTOR0805-RES 0805 Resistor
R3 15 K RESISTOR0805-RES 0805 Resistor
R4 33 K RESISTOR0805-RES 0805 Resistor
R5 12 K RESISTOR0805-RES 0805 Resistor
R6 8,2 K RESISTOR0805-RES 0805 Resistor
R7 5,6 K RESISTOR0805-RES 0805 Resistor
R8 100 K RESISTOR0805-RES 0805 Resistor
U1 MCP73831 MCP73831 SOT23-5 Miniature single cell, fully integrated Li-Ion, Li-polymer charge management controller IC-09995
Step 4: Fail
I make an error with the implement of the mosfet.
but when i receive my board i want to test it .
i put the mosfet on an adapter and wire it on the board
and it works!!