Texas Instruments Incorporated
Low dropout regulator (LDO) circuit with smooth pass transistor partitioning

Abstract:

A system includes a battery. The system also includes a low dropout regulator (LDO) circuit with an input coupled to the battery and the LDO circuit. The system also includes a load coupled to an output of the LDO circuit. The LDO circuit includes an error amplifier and a control circuit coupled to the error amplifier. The LDO circuit also includes a first pass transistor coupled to the control circuit and configured to provide a first pass current as a function of load current according to a first continuous conduction curve. The LDO circuit also includes a second pass transistor coupled to the control circuit and configured to provide a second pass current as a function of load current according to a second continuous conduction curve.