DIY - Single Cell Lithium-ion Battery Charger

 

• The current circuit charging current capacity is 500mA 
• Select the MOSFET based on the current requirements
• 100 milliohms resistor is a current sense resistor and based on the current to load the sense resistor has to be changed
• A rechargeable single lithium ion battery (3.7V) is connected at the output of the MCP73826 for charging
• The shutdown pin is always pulled up with 100K resistor to keep the MCP73826 in Active mode
• The MCP73826 turns the GATE of NDS8434 to OFF condition if the sense voltage exceeds the threshold voltage. The sense voltage is fixed inside the MCP73826