Linear LNAs boast miniscule noise figures at 2 GHz

SILICON (Si) bipolar complementary metal-oxide semiconductor (BiCMOS) still has room for improvement, as demonstrated by a pair of low-noise amplifier s (LNAs) designed and develop by Philips Semiconductors (Sunnyvale, CA). Fa bricated with the firm's QUBiC4 0.25-mum Si BiCMOS process, these amplifier s do not require the additional germanium (Ge) doping las in SiGe) to achie ve noise figures of 1.1 dB or less at 2 GHz. With performance that rivals t hat of gallium arsenide (GaAs) and SiGe LNAs, one of the designs exhibits a noise figure of 0.99 dB and third-order intercept of +5 dBm at 2 GHz while using only 4-mA current, while the other amplifier features a noise figure of 1.1 dB and third-order intercept of +9 dBm with 6-mA current.