We present an ASIC dedicated to the CCD controller. The SPA (Signal Processing ASIC, SPA) process one CCD output channel: amplified the CCD output analog signal, correlated double sampling, converted into differential signal. This chip is highly configurable, with both readout speed and gain adjustable, in order to fulfill the various read-out requirements of astronomical CCD, such as fast readout for wide-field imaging, high-gain and low-speed readout for spectroscopy imaging, etc. At present, the chip has obtained three performance standard models available for mass production: SPA-1ch, SPA-2ch, SPA-4ch, respectively to provide 1,2,4 CCD output signal processing. The SPA chips are encapsulated by the SIP process. The size and operating temperature allow to integrate the SPA chips in-cryostat, very close to the CCD sensor. The SPA can help to form a more compact CCD control circuit. Design process and the results of performance tests of the SPA-4ch chip are reported in detail.
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