Wideband (500 MHz) 16 bit dynamic range current mode PreAmplifier for the CTA cameras (PACTA)

Abstract

A wideband current mode preamplifier with 16 bits dynamic range (DR) is presented. It has been designed for the cameras of the Cherenkov Telescope Array (CTA). A novel current division scheme at the very front end part of the circuit splits the input current into two scaled currents which are connected to independent current mirrors. The mirror of the high gain path comprises a saturation control circuit for accurate current division. Measurement results of an ASIC designed in Austriamicrosystems 0.35 μm SiGe technology are presented: 500 MHz BW, 16 bits DR, 10 pA/sqrt(Hz) input referred noise current and relative linearity error below 3%.