IDE3381 APOCAT

Product Description

Summary

IDE3381 APOCAT – the Array of Photon Counters Above Threshold is an integrated circuit (ASIC) for reading out up to 16 photomultiplier tubes (PMTs) and silicon photomultipliers (SiPMs). With scintillators, it is ideal for high-resolution x-ray and gamma-ray pulse-height spectroscopy, or photon timing and 4-bin energy resolved photon counting at high data rates up to 1Mcps per channel, synchronously or asynchronously per channel. The ASIC was originally designed for space missions, but thanks to on-chip ADC and versatile registers, it can be programmed for other use cases including low-power terrestrial applications with PMTs and SiPMs.”

General Description

The IDE3381 is an integrated circuit (IC) for the readout of photon detectors, e.g., photomultiplier tubes (PMTs), silicon photomultipliers (SiPMs). The IC has 16 channels and 1 summing channel. Each channel can be used for high-resolution pulse-height spectroscopy, timing and 4-bin energy resolved 18-bit counting. The readout was designed for relatively high rates of about 1Mcps per channel. The channels can operate synchronously or asynchronously. The channel is programmable for peaking time of 50 ns, 150 ns, 300 ns, or 2000 ns to allow for pulse-height spectroscopy using various scintillators. Each channel has a current-mode input stage (CMIS) followed by a charge sensitive amplifier (CSA). The CMIS is designed for large negative charges and its attenuation can be programmed to be 1, 2.5, 5, 10, or 20. The CMIS input potential is programmable individually for each channel for operation with DC-coupled SiPM/MPPC array readout. The CMIS is ideal for relatively large detector capacitance (several nF) and large detector leakage currents (-10 μA from dark counts). The CMIS can be bypassed to allow for either positive or negative charge directly into the CSA. The CSAs have individually programmable conversion gain of 46, 48, 51, 53, 55 or 265mV/pC. The IC contains one 12-bit analog-to-digital converter (ADC) that allows for digitization of the pulse heights from all channels, including the summing channel at a sampling rate of 2 Msps (FN-about-ADC). Every channel has 2 outputs: one analog output for the pulse height and one digital output for the trigger/timing pulse with fixed width or time-over-threshold. The outputs facilitate many applications, such as external digitization, pulse height and time spectroscopy, pulse counting, triggering, and time-over-threshold. The IC operates at 3.3-V supply voltage and dissipates about 360 mW with both CMIS and on-chip ADC active. To save power, any channel or function can be powered down. The ASIC has a serial peripheral interface (SPI) for programming its register settings and for the readout of ADC and counter data. Fast readout with up to 16 Mbit/s is possible via a serial data transmission line. The IC has been designed to be latch-up immune and resilient to single event upsets.

FN-about-ADC: The ADC data output at TXD_O is not working correctly. We recommend using the chip without the on-chip ADC until the bug is fixed.

Applications

The IDE3381 has been designed for high-rate and high-resolution x-ray and γ-ray spectroscopy with scintillators and PMTs or SiPMs.

Publications

• Q. Wan, Y. Zhang, J.H. Guo, Y.Q. Zhang and X. Xu, 2022, “Design of front-end electronics for HXI spectrometer flight model on-board ASO-S satellite”, Journal of Instrumentation, Volume 17, February 2022, https://doi.org/10.1088/1748-0221/17/02/P02020