A New High-Efficiency Voltage Regulator

Conventional dc voltage regulators suffer from poor efficiency due to the large voltage drop across the series pass transistor. Generally, a minimum of 2 to 3 volts is necessary across the pass transistor for proper operation of the regulator. A new regulator circuit is presented in this paper where the voltage drop across the pass transistor can be as little as one VBE drop even under full load. Due to the small voltage drop, the dissipation in the pass transistor is considerably reduced and low-power transistors can be used. This yields an efficient and cheaper regulator design. An efficiency of 95 percent has been achieved with this regulator.