Red Dog Physics

CD48 Coincidence Counter/Detector

CD48 Coincidence Counter/Detector

Based on the Cypress PSoC5 chip, this device was originally designed for use with Quantum Optics single-photon experiments. It uses edge detection to bring the time sensitivity down to roughly 25 nanoseconds, sufficient for excellent results when used with quantum optics experiments. It is also useful for nuclear coincidence detection, muon telescopes, half-life measurement, and anything else needing a configurable counter.

  • Platform-independent USB interface.
  • Text-based commands: can be controlled by any serial-capable computer language, or even just a terminal window.
  • 4 BNC inputs.
  • 8 independent counters. Counters 0-6 are 24-bit (16,777,215 max count) and counter 7 is 16-bit (65,535 max count).
  • Any counter can be assigned to count events on any input or combination of inputs. If a counter is assigned to watch multiple inputs, it counts coincidences between those inputs.
  • User-selectable input impedance (50-Ohm or high-Z).
  • User-selectable trigger level, 0-4.02V.
  • 8-bit analog output (0-4.02V) for experiment control
  • Reports counts either on demand, or at time intervals controlled by an internal clock.
  • LEDs display activity at each input as well as at each counter.
  • Additional LED indicators for counter overflow, communications, and data.
  • The CD48 stores all settings; any time you turn it on it remembers its last configuration.
  • Built-in help functionality, just send it an 'H' command.

Price: $300

In stock: 3 (25 more expected 8/1/19)

Send an email to to make an order.



  • LabVIEW 2017 programs
  • Python and MatLAB programs coming soon!


Please note: The information provided here is sufficient to make your own CD48. You can create gerber files from the KiCAD files, send those gerbers to a manufacturer to have them build the board for you, and program that board using PSoC Creator. This is a lot of work, and is expensive in small batches of boards; so we hope that you consider your own time to be valuable enough that it's actually more economical to buy one from us.

These design files are released under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) license.

Quality lab equipment at a fetching price,

no bones about it!