We present two cryogenic Application Specific Integrated circuits (ASIC's) realized with a GaAs MESFET process. A single-channel differential or double-channel singleended voltage sensitive preamplifier for 4.2 K operation, to be used with bolometric detectors, was realized and tested. A very simple structure working as a unity gain buffer or as a transconductance amplifier, or even as a shapin...

A fully integrated GaAs MESFET active inductor is presented in this paper with independent voltage tunable inductance and series-loss resistance. The measured inductance is tunable from 65 to 110 nH in the frequency range from 100 MHz to 1.0 GHz. The measured loss resistance is independently tunable over a 5.6to+20.8range corresponding to a 0.26 and 0.65 V change in dc tuning voltages, respecti...

A simple method for transistor DC parameter extraction is presented, where the self-heating of the transistor is taken into account. The thermal behaviour of the transistor is modelled using a single thermal resistance, whose value is extracted simultaneously with the electrical parameters. When pulsed measurements are performed the usage of the thermal resistance, as an effective thermal resis...

In this paper, large-signal intermodulation distortion (IMD) sweet spots in microwave power amplifiers are studied and predicted using a new mathematical basis. The variations in the IMD versus drive pattern with active bias point and the terminating matching networks are investigated. This nonlinear distortion model enabled the design of power amplifiers specially tailored to present a desired...