ABSTRACT
Various kinds of imagers with alternative levels of resolutions are used in many space applications. The analog electronics used for these imagers are very similar to the ones seen in terrestrial imaging devices and include low noise charge detection and conversion amplifiers and low capacitance analog-to-digital converters. The conversion of the amplified signal to digital equivalent does require a low power high resolution and radiation-tolerant instrumentation quality ADC. The ubiquitous building block circuit for analog electronics and the avionic systems mentioned earlier are operational amplifiers. The input, or pre-amp, stage was designed to be a high gain amplifier with a rail-to-rail input common-mode range (ICMR), low offset, and the necessary voltage protection circuitry. Minch bias circuitry and associated bias mechanisms are used to generate the necessary voltages, allowing them to track with temperature, maintaining the ICMR of the amplifier, while providing cascode protection to the input pairs. Voltage management for this stage involves both static and dynamic voltage protection.
