Analog CMOS peak detect and hold circuits. Part 2. The two-phase offset-free and derandomizing configuration

An analog CMOS peak detect and hold (PDH) circuit. which combines high speed and accuracy, rail-to-rail sensing and driving, low power, and buffering is presented. It is based on a configuration that cancels the major error sources of the classical CMOS PDH, including offset and common mode gain. by re-using the same amplifier for tracking, peak sensing. and output buffering. By virtue of its high absolute accuracy. two or more PDHs can be used in parallel to serve as a data-driven analog memory for derandomization. The first experimental results on the new peak detector and derandomizer (PDD) circuit, fabricated in 0.35 mum CMOS technology, include a 0.2% absolute accuracy for pulses with 500 ns peaking time, 2.7 V linear input range, 3.3 mW power dissipation, 250 mV/s droop rate, and negligible dead time. The use of such a high performance analog PDD can greatly relax the requirements on the digitization in multi-channel systems. (C) 2002 Elsevier Science B.V. All rights reserved.