A 10GS/s 2V/sub pp/ emitter follower only track and hold amplifier in SiGe BiCMOS technology

This paper presents an emitter follower only track and hold amplifier (THA) in 0.25/spl mu/m SiGe BiCMOS complementary HBT technology. By using a sequence of pnp and npn emitter followers (pnp-npn EF), we enhance the linearity of the THA input buffer for an input signal of 2Vpp. The THA achieves 8bits of accuracy at 10GHz of sampling rate with a 3GHz 2Vpp input signal. This is about three bits more than currently reported 10GS/s THAs in npn-only technology at this wide signal swing.