Patent ID: 6452454
Filing Date: 2002-09-17
Classification: H03F

Abstract:
A bias system including a current mirror and a radio frequency transistor, the current mirror having a temperature compensation module to compensate for changes in current mirror reference current that occur over a temperature range comprising:a reference voltage node; a current mirror comprising: a first transistor having a base, a collector and an emitter; a second transistor having a base, a collector and an emitter, wherein the base of the first transistor connects to the base of the second transistor at a base node; a resistor having a first terminal connected to the reference voltage node and a second terminal connected to the base node; a third transistor having a base, a collector, and an emitter, wherein the collector of the third transistor connects to the base node, and wherein the base of the third transistor connects to the emitter of the first transistor; and a compensation module connected to the base node, the compensation module configured to selectively draw current from the base node in response to temperature changes.