12V 4A Solar Photovoltaic Battery Charger
This is the circuit diagram of 12 Volts, 4 Amperes Solar Photovoltaic (PV) battery charger which will be suit to charge a 12V battery or accumulator. The circuit handles up to 4 amps of current from a solar panel, which equates to about 75 watts of power. A charging algorithm called “pulse time modulation” is introduced in this design. The current flow from the solar panel to the battery is controlled by an N-channel MOSFET, T1. This MOSFET does not require any heat sink to get rid of its heat, as its RD-S(on) rating is just 0.024 Ω. Components List: R1 = 15kΩ R2,R3 = 3.3kΩ 1% R4 = 2.2MΩ R5 = 1kΩ P1 = 5kΩ preset C1 = 22μF 25V, radial D1 = MBR1645G (ON Semiconductor) D2 = LED, 5mm IC1 = TL431ACLP (Texas instruments) T1 = IRFZ44NPBF (International Rectifier) T2 = 2SC1815 (Toshiba) (device is marked: C1815) T3 = BC547 Miscellaneous: K1,K2 = 2-way PCB terminal block, lead pitch 5mm How the circuit works: Schottky diode D1 prevents the battery discharging into the solar panel at night, an...