Low Quiescent Current SiGe HBT Driver Amplifier Having P-MOSFET Current Mirror Type Self Bias Control Circuit

Abstract

An L-band low quiescent current and low distortion SiGe HBT driver amplifier having a self base bias control circuit is described. Since the size of this circuit is small and it does not need external control circuit, it is easy to integrate with the driver amplifier on single chip. According to the output power level, the self base bias control circuit, which is the combination of a P-MOSFET current mirror and a conventional constant base voltage circuit, automatically controls the base voltage and allows low quiescent current at low output power level and low distortion at high output power level. The simulated result shows that the proposed driver amplifier realized P1dB improvement of3.0dB compared with the conventional constant base voltage driver amplifier under the same quiescent current condition. The fabricated amplifier achieved P1dB of 14.9dBm with quiescent current of 15.3mA.

SiGe W-CDMA transmitter for mobile terminal application

“…The Class-AB design was chosen to achieve high linearity and low noise for minimum bias current of 16 mA. High-breakdown ( ) high-linearity SiGe HBTs [8], [9] are used to achieve very high linearity for low quiescent current consumption. The driver provides 14-dB gain, 4-dB NF, and 15-dBm output P1dB while consuming only 16 mA of quiescent current at 7-dBm output power.…”

Pre-distortion linearizer using self base bias control circuit

“…In order to realize PA's having both characteristics for mobile terminals, intelligent bias control circuit configurations have been proposed. As one of the intelligent bias control circuits, the self base bias control circuit was proposed [1], and it automatically controls the bias condition according to the output average power level, and allows the low quiescent current at low output power and high dB P 1 characteristic at high output power. In other words, this circuit configuration also controls the gain and phase characteristics according to the output power level.…”