Monitoring and switching circuit for solar powered supply - controls charging and discharging of internal battery via power MOSFET

摘要

The solar panel output can be connected to the load directly as well as the battery or can be used to charge the battery during off-load periods. The panel output can also be totally disconnected when battery discharge is required. The present application concerns the load voltage monitoring and switching circuit. The battery terminals (W1,W2) are connected to the circuit load (RL) via a power MOSFET (T1). The load voltage (VD) is fed to one input of a differential amplifier (A1), the other input being fed by a reference voltage (K). The difference voltage (VA) is fed to the external control circuit and the resultant control signal (Z) is fed to the MOSFET gate via a blocking diode (D1).