A 16 CHANNEL PEAK SENSING ADC FOR SINGLES SPECTRA IN THE FERA FORMAT

To read out multi-element small X-ray detectors for X-ray fluorescence applications with synchrotron radiation one needs the capability to r ecord multiple singles spectra for each detector element at high rates . We have developed a sixteen channel 11 bit peak sensing ADC in a CAM AC module. We use the FERA readout bus to place the data into a commer cially available histogramming module developed to generate multiple h istograms from FERA ADCs. The sixteen channels digitize shaped pulses from the detectors without external gating. The digitizing time is 8 m u sec, the peak acquisition time is greater than or equal to 2 mu sec. The module contains a LIFO to permit block transfers in order to mini mize dead times associated with the readout. There is a common CAMAC c ontrolled analog threshold for noise suppression and a 16 bit mask to enable or disable individual ADCs. Differential non linearity is less than +8% / -4%. A gamma-ray spectrum collected using this ADC is prese nted.