Design and initial test results of a CCD fan-out board with integrated preamplifier and ESD protection for the scientific instrument ELMER at the GTC 10-m telescope

摘要

The scientific instrument ELMER for the GTC 10-m telescope integrates an E2V Technologies CCD44-82 detector and can optionally use the MIT/LL CCID-20 device. Fan-out electronics have been developed that support both detectors reusing the same PCB design and cabling. The main system component, the fan-out board, provides dual-channel input clamp and preamplification of the CCD output signal as well as filtering and active ESD protection of all the CCD lines within a 60x80mm envelope. The preamplifier stage is based on complementary bipolar operational amplifiers with dielectric isolation technology for optimum noise performance and minimum settling time. Matched, discrete JFET buffers are used for improved DC precision. Preliminary tests performed on the system yield 2.0μV_(rms) preamplifier noise after CDS at 50kHz readout frequency. Slew rate in excess of 230V/μs and settling time well below 75ns have been obtained for a gain 4 preamplifier configuration driving non terminated coaxial cable.