128 Channel with CDS and Sample-and-Hold

The VASCM3.2 is a 128 channel low-noise/low power current sensitive preamplifier-filter circuit, with two-channel alternating sample and hold. The ASIC has switched current mode, correlated double sampling and dead time free readout. The integrated signals are read out by a serial multiplexer after S/H. The VA_SCM3.2 design is based on the existing VA_SCM2. Four gain settings with dynamic range: 1pC, 2.5pC, 6pC, and 20pC at 1.5V output voltage. Also, includes means for Correlated Double Sampling (CDS) and can be used in a separate operational mode.

Keywords: Current mode x-ray readout, portal imaging, Current mode x-ray readout, portal imaging, radiation dosimetry, CDS, variable gain, pre-amplifier

Product Features

DetectorsSilicon, thin-film transistor (TFT) arrays
ApplicationImaging, Spectroscopy, Calorimetry
Number of inputs128
Input charge range4 gain settings: ±1 pC, ±2.5 pC, ±6 pC and ±20 pC
OutputsMultiplexed pulse height with CDS
Test and calibrationInternal calibration circuit


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  • Fedorovich, O., et al. "Metal micro-detectors: Development of «transparent» position sensitive detector for beam diagnostics." Problems of Atomic Science and Technology, Series «Plasma Physics 6.82 (2012): 196-198, VANT