A low-voltage, micro-power 1 A switching regulator

A switching regulator circuit that is capable of operation at supply voltages down to 1.0 V and consumes less than 100 mu A with no load, making it attractive in battery operated systems where long battery life is important, is discussed. The circuit can deliver 5 V at 50 mA with a 1.5-V input. Unlike previous low-voltage circuits, which are limited in output power, this circuit incorporates micropower control circuitry and a 1-A power switch. A low-saturation-voltage bipolar technology with implant resistors and a deep p/sup +/ diffusion for high-current lateral PNPs is used to implement the circuit. A 1-A NPN switch with a saturation resistance of 0.6 Omega and a 30-mA low-saturation lateral PNP, along with all control circuitry, are integrated on a single die.<
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