Regulator for charging a rechargeable storage device from a photovoltaic cell

摘要

A circuit regulates charging of a rechargeable storage device having a pair of device terminals by a photovoltaic cell having a pair of cell terminals. The circuit has a pair of input terminals for coupling to the cell terminals and a pair of output terminals for coupling to the device terminals. The circuit includes a switch for selectively establishing and breaking an electrical connection between the input terminals and the output terminals and a variable resistor coupled to the device terminals for providing a signal proportional to a terminal voltage across the output terminals. The circuit also includes first and second operational amplifiers responsive to the signal and respective first and second voltage limits, each operational amplifier causing the switch to establish an electrical connection between the input terminals and the output terminals when the signal is equal to a predetermined proportion of the respective voltage limit. The circuit may be coupled in a solar-powered charging system between a photovoltaic cell and a rechargeable storage device.