A fast, low power amplifier, shaper and discriminator for high rate straw tracking systems

The ASD-8 is a bipolar integrated circuit that provides eight channels of amplifier, shaper, and discriminator on a 2.8*4.7 mm silicon substrate. It was designed for use in the straw-based central tracking system of the SDC detector. Competing requirements for short measurement time ( approximately= 15 mW/ch), and low operational threshold ( approximately=1 fC) led to the choice of a largely differential circuit which includes detector tail compensation. Threshold control with lockout is provided for each discriminator. Tests with parts from a recently fabricated prototype run indicate excellent yield and stable operation with little or no internal crosstalk.<>