A high speed, low noise ASIC preamplifier for silicon strip detectors

A first-version Tektronix Quickchip semicustom ASIC (application-specific integrated circuit) preamplifier for silicon strip detectors was reported previously (see D. Christian et. al. 1988). An improved version, QPA02, has been designed. It incorporates laser trimming of nichrome resistors as a means of compensating for chip resistance process variations, which affected the response of the first version. This allows chips with randomly varying resistance values to be trimmed to a standard output pulse shape. The QPA02 also has improved performance specifications. The design philosophy and specifications of the QPA02 are described. The QPA02 has been tested and demonstrated to be an effective silicon strip amplifier for high-rate applications, performing as modeled.<
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