GaAs readout electronics for particle detectors

A monolithically integrated GaAs frontend will be presented consisting of a Charge Sensititve Preamplifier (CSP) and a shaper with a time constant of tau(ind M) = 12 ns and an amplification of 43.7 mV/fC into 50 Ohm. The circuit is based on 0.3 micron double pulse doped pseudomorphic HEMT transistors with a maximum f(ind t)(max) = 50 GHz. To demonstate the funcionality of this electronics the diced chip was connected to a 200 micron thick, 1x1 qmm large GaAs pad detector and spectra of Minimum Ionizing Particles (MIP) were recorded. On another chip a binary readout design was investigated based on the concept of a transimpedance amplifier followed by a univibrator. The performance of that chip will also be presented.