A 3.6 GHz BW, 8 GSamples/s, high IIP3 track-and-hold amplifier with Schottky diode and high linearity buffer in GaAs HBT technology

摘要

This paper presents a high-speed, low distortion track and hold amplifier (THA) in GaAs HBT. A series sample Schottky diode is added to switch emitter follower in order to improve the stability and speed of THA. Perturbation technique is used to analyze and discuss the nonlinearity distortion of input buffer, CAD results verifies the hand analysis. Experimental results show that the prototype THA achieves IIP3 more than +20dBm up to entire small-signal bandwidth of 3.6GHz with a sample rates of 8 Gs/s, and a SFDR of better than 38dB at 3GHz. In addition to HBT technology, DHBT and other technology can be used in this proposed THA.