A configurable voltage regulator (28; 128) operable in either of two selectable modes or topologies is disclosed. In one disclosed embodiment, the voltage regulator (28) can operate as a linear regulator or a switching regulator. A gate driver (35) and an error amplifier (36) is used in each mode. Configuration switches (34) are controlled by a configuration amplifier (40) to connect the error amplifier (36) to the gate driver (35) in the linear regulator mode, or to connect the error amplifier (36) to circuitry (42, 44, 46) for controlling the gate driver (35) in switching regulator mode. In another disclosed embodiment, the voltage regulator (128) generates a negative polarity regulated voltage according to a switching regulator or charge pump topology.