A 20-Gs/s Track-and-Hold Amplifier in InP HBT Technology

Abstract

This paper presents a 20-Gs/s track-and-hold amplifier (THA) fabricated InP HBT technology. This THA is capable of operating under relatively high input voltages. The THA uses a fully differential architecture with a switched emitter–follower. To mitigate the pedestal error due to the feedthrough attenuation network, we added degeneration resistors in the feedthrough attenuation block. Measured total harmonic distortion is below <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$-{\hbox{40 dB}}$</tex></formula> at low input frequencies, and <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$-{\hbox{18 dB}}$</tex> </formula> at frequency of 9.9 GHz.