A 2.5-GS/s 62dB THD SiGe Track-and-Hold Amplifier with feedthrough cancellation technique
In this paper a Track-and-Hold Amplifier (THA), designed in a low cost 0.35μm SiGe 60GHz technology is presented. Thanks to the joint action of a novel input buffer and a suppression feedthrough architecture, it is able to guarantee 62dB Total Harmonic Distortion(THD) up to a frequency of 2.2GHz with 0.9Vp-p differential input at a sampling rate (Fs) of 2.5GS/s. The THA core draws about 145mA from 3.5V supply.
A 11-bit Track and Hold Amplifier in 0.25 µm SiGe BiCMOS for RF sampling receivers
The paper describes a Track and Hold Amplifier (THA) suitable for RF sampling and Software Defined Radio receivers where high speed and high resolution are required. The reported THA is based on two main techniques: one for minimizing the differential droop rate and one for improving the HD3 in track mode. Measurements results show that the adopted solutions are both effective. In the desired input band around 1GHz, at the desired sub-sampling frequency (0.5GS/s) the THA provides a linearity compatible with 12-bit (Spurious Free Dynamic Range, SFDR). Moreover at the maximum achievable sampling frequency (1.5GS/s) the performances are quite constant and the resolution is compatible with 11-bit (SFDR) up to an input frequency of 1GHz.
A 20-Gs/s Track-and-Hold Amplifier in InP HBT Technology
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 -40 dB at low input frequencies, and -18 dB at frequency of 9.9 GHz.