Patent ID: 7193452

Claim:
A temperature-compensated bias circuit for a power amplifier comprising: a first resistor (Rref) connected to a reference voltage is connected to a base terminal of a third transistor (Q 3 ) and an emitter terminal of the third transistor is connected to a first diode (D 1 ); a second resistor (R 1 ) connected to the reference voltage; a third resistor (R 2 ) connected to the second resistor in series; a fourth resistor (Rc) having one terminal connected to the reference voltage; a fifth resistor (Re) having one terminal connected to ground; a bias transistor (Q 4 ) having a base terminal connected to a contact point (VS) between the second resistor and the third resistor, a collector terminal connected to the other terminal of the fourth resistor, and an emitter terminal connected to the other terminal of the fifth resistor; and a sixth resistor (Rf) connected between a collector terminal of the third transistor and a collector terminal of the bias transistor.