CITIROC 1A

Important Notice – CITIROC 1A Lifecycle Update
The CITIROC 1A ASIC is gradually approaching the end of its lifecycle as its underlying manufacturing technology becomes obsolete. We would like to reassure our customers that a substantial—though finite—quantity of CITIROC 1A devices remains available, subject to stock availability. Based on current forecasts, this inventory is expected to support new demand for approximately the next five years, ensuring continuity for your projects.

For CAEN products based on CITIROC 1A (A5202 / DT5202), we expect to continue supplying new units throughout this timeframe. In addition, maintenance and service support will remain available for roughly ten years, in line with our long-term commitment to product reliability and customer service.

In parallel, Weeroc has developed RADIOROC, the next-generation ASIC designed as the natural evolution of CITIROC 1A. RADIOROC is recommended for all new designs, and a new FERS-family product based on this ASIC (A5204 / DT5204) is currently in development and will be introduced soon.

If you are planning new systems or considering future migration options, our team is ready to provide guidance and support for both CITIROC-based solutions and the upcoming RADIOROC platform. We are committed to ensuring a smooth and well-supported transition for all our customers.

CITIROC 1A is a 32-channel front-end ASIC designed to readout silicon photo-multipliers (SiPM) for scientific instrumentation application.
CITIROC 1A allows triggering down to 1/3 pe and provides the charge measurement with a good noise rejection. Moreover, CITIROC 1A outputs the 32-channel triggers with a high resolution timing (better than 100 ps).
An adjustment of the SiPM high-voltage is possible using a channel-by-channel DAC connected to the ASIC inputs. That allows a fine SiPM gain and dark noise adjustment at the system level to correct for the non-uniformity of SiPMs. CITIROC 1A can be calibrated using a unique calibration signal.
Timing measurement better than 100 ps RMS jitter is measured on single photo-electron along with 1% linearity energy measurement up to 2500 p.e. The power consumption is 225mW/ASIC when all stages are ON.