Abstract: For matching the electrical impedance of a photovoltaic power source and a load, a switching regulator circuit has properties especially suited to the conversion of photovoltaic power to electric power. The circuit regulates the source voltage for maximum power output and supplies a load voltage equal to the regulated source voltage. The circuit comprises two branches: one in which a switching transistor (38), a diode (40), and filter components (30) and (42) provide a positive voltage; and the other in which similar components (22, 32, 24, and 44) in a different configuration, provide a negative voltage. The load voltage is the sum of these and is equal to the input voltage. Since the source voltage is substantially constant, the switching regulator in effect converts the photovoltaic power source to a constant-voltage source. The circuit provides improved performance and thus enhances the utility of photovoltaic power sources.