Voltage regulator structure that is operationally stable for both low and high capacitive loads

摘要

A regulator structure includes a first differential amplifier having a first input coupled to a reference voltage node. A second differential amplifier has a first input coupled to the output of the first differential amplifier. A third differential amplifier has a first input coupled to the output of the first differential amplifier. A first pmos transistor has its gate coupled to the second differential amplifier output, and its drain coupled to a second input of each of the first and second differential amplifiers. A second pmos transistor has its gate coupled to the third differential amplifier output, and its drain configured to output a regulated voltage which is also a second input of the third differential amplifier. A circuit is configured to replicate the regulated voltage and couple the replicated regulated voltage to the drain of the first pmos transistor.