PicoTDC: a flexible 64 channel TDC with picosecond resolution

Abstract

The PicoTDC is a 64 channel TDC (Time to Digital Converter) ASIC, with 3ps or 12ps time binning, developed at CERN for use in a large variety of high channel count scientific instrumentation. Acquired time measurements are processed on-chip with a programmable buffering and triggered data flow architecture before being read out on 1 to 4 byte-wise readout ports with a total readout bandwidth of up to 10 Gbps. Leading edge, falling edge or leading edge together with pulse width can be captured at burst rates as high as 1.2 GHz and sustained rate of 320 MHz per channel. Effective single-shot time resolution has been measured to be 3.7 ps RMS across all 64 channels over its full dynamic range and as good as 1.35 ps RMS when using an on-chip adjustment feature optimized for a specific channel (0.43 ps if averaged over multiple measurements). The PicoTDC is implemented in a 65 nm CMOS process and 20 k chips have been produced and packaged in a 400 pin plastic BGA package.