Title :
A 2.7-V SiGe HBT variable gain amplifier for CDMA applications
Author :
Kim, Chang-Woo ; Kim, Young-Gi
Author_Institution :
Coll. of Electron. & Inf., Kyung Hee Univ., Kyunggi-Do, South Korea
Abstract :
A monolithic SiGe HBT variable gain amplifier with high dB-linear gain control and high linearity has been developed for CDMA applications. The VGA achieves a 30-dB dynamic gain control with a control range of 0-2.7 Vdc in 824-849 MHz band. The maximum gain and attenuation are 23 dB and 7 dB, respectively. Input/output VSWRs keep low and constant despite change in the gain-control voltage. At a low operation voltage of 2.7 V, the VGA produces a 1-dB compression output power of 13 dBm and /spl plusmn/885-kHz ACPR of -57 dBc at a 5-dBm output power.
Keywords :
Ge-Si alloys; MMIC amplifiers; bipolar MMIC; cellular radio; code division multiple access; gain control; 2.7 V; 30 dB; CDMA applications; MMIC design; SiGe; cascade connection; dynamic gain control; gain-control voltage; linear gain control; low operation voltage; monolithic HBT variable gain amplifier; Circuits; Cutoff frequency; Gain control; Germanium silicon alloys; Heterojunction bipolar transistors; Linearity; Multiaccess communication; Power amplifiers; Power generation; Silicon germanium;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2003.819959
