The guiding camera board architecture is similar to that of the main camera, but simpler, using analog switches alone to generate all the CCD clock phases. The clamp and hold circuitry, power supplies and temperature sensing circuits are identical to those used on the KAF401/1602 CCD board. The CCD is directly mounted on the board, which has a slot milled to accept the CCD cold finger. The clock board is designed around the inexpensive (but obsolete!) Texas Instruments TC-211 sensor.

Clock drivers

The clocks are generated using fast analog switches (ADG453). The board implements sample hold for the TC-211 by generating a three level clock on the serial register gate (SRG) of the CCD. The reset level is sampled during the intermediate voltage level of SRG. Antiblooming has been disabled and the CCD is not capable of horizontal binning. Although vertical binning is possible, it has not been implemented in the Pyxis controller firmware.

Schematics for the clock driver board.