Automated, adaptive, fast reset circuit for wide-energy range detector front-end

Abstract

In this article, we present a front-end amplifier that is equipped with a precise, fast, and automated reset circuit responsible for two actions: restoring the charge-sensitive amplifier output voltage from a pulse level to baseline, and the analog-to-digital conversion of the pulse amplitude. Importantly, the circuit is self-clocking, which allows to take advantage of the modern submicrometer CMOS process, and thus speed-up the reset and conversion phases. Thanks to the proposed approach, the fast clock signal distribution and an independent analog-to-digital converter per channel are not required, saving both the power consumption and the silicon area. The presented circuitry was adopted into 100-pixel-shaped recording channels and sent for fabrication in the CMOS 28 nm process.

A prototype Radiation Energy Measuring Integrated Circuit with an asynchronous current-pulse reset block providing analog-to-digital conversion in 28 nm CMOS

“…As a result, the CTRL starts the conversion procedure with a time delay that is required for the CSA output pulse to reach its peak value V OUT,Peak . The energy conversion is based on short current pulses I DIS injected at the CSA input to compensate the charge stored at the feedback capacitance C F (for further details see [11]). The whole conversion process is terminated when the CSA output voltage reaches the reference voltage level V R generated by the replica amplifier CSA R .…”