An 8/spl times/8 pixel IC for X-ray spectroscopy

An integrated circuit (IC) providing 64 channels of low-noise signal processing electronics in an 8/spl times/8 pixel arrangement has been developed as part of an integrated silicon detector array for high count-rate X-ray spectroscopy applications. Each pixel features low-noise charge integration, programmable peaking time and gain, and an output driver. The 8/spl times/8 pixel IC builds upon our previous development of the XPS chip, a 1-dimensional (1-D) preamplifier-shaper IC for linear silicon detector arrays. The new pixel design features significant improvements to the shaper and output driver stages, including digital peaking time and gain selection, and a low-power charge driver/receiver design. When operated with a cooled, low-capacitance silicon detector, an energy resolution of /spl sim/210 eV FWHM was obtained for 5.89 keV X-rays. The power dissipation is /spl sim/6 mW per pixel at a supply voltage of 3.3 V.