Patent ID: 7304541

Claim:
A voltage regulator for a monolithic microwave integrated power amplifier circuit comprising: a first HBT transistor having a first collector current; a second HBT transistor arranged as a current mirror with the first transistor, where the collector current of the second HBT transistor mirrors the first collector current; first and second resistors disposed in series between the collector of the first HBT transistor and a voltage source, the first and second resistors providing a path for the first collector current, the point electrically between the first and second resistors defining a first voltage; and a third HBT transistor with its collector functionally connected to the first voltage point and a third resistor functionally connected from the collector to the base of the third HBT transistor, wherein the third HBT transistor conducts more or less current away from the first voltage point when the voltage source rises or falls, respectively, wherein the voltage at the first voltage point remains substantially constant.