A Wideband SiGe Power Amplifier Using Modified Triple Stacked-HBT Cell

This letter presents a linear wideband differential optical driver amplifier in a 90-nm silicon germanium (SiGe) bipolar-complementary-metal-oxide-semiconductor (BiCMOS) process. The amplifier utilizes a modified triple-stacked heterojunction bipolar transistor (HBT) topology with emitter degeneration to achieve high output voltage swing and high linearity. The amplifier achieves 13.2-dB voltage gain with a bandwidth from dc to 53 GHz. The amplifier can deliver a 4-V peak-to-peak differential (Vppd) with a total harmonic distortion (THD) of 1.6% at 1 GHz. The amplifier consumes 630-mW dc power at the small-signal operation.