A Frontend Asic For A Silicon Avalanche Photodiode Linear Array Detector For Synchrotron X-Ray Experiments

We designed a frontend ASIC of a silicon avalanche-photodiode (Si-APD) array detector for time-resolved measurements using pulsed synchrotron X-rays. The Si-APD detector had 64 pixels of a linear array. A pixel size of 100 mu m by 200 mu m with a 50-mu m gap between pixels, a thickness of 10 mu m and a sensitive region of 9.6 mm long were designed in the linear array. In order to apply the APD detector to time-resolved diffraction measurements with 2-ns pulse-pair resolving time and a count rate of up to > 10(7) s(-1), a four-channel ASIC of 4x4 mm(2) in size was newly developed for processing a nanosecond-width pulse from each pixel of the Si-APD. The ASIC consisted of a current amplifier with a baseline restorer, a comparator, T-flip flops and PECL drivers.