The GSI event-driven TDC with 4 channels GET4

The GSI Event-Driven TDC GET4 is the first prototype of a high resolution low power event-driven TDC for the CBM-time of flight detector readout. The design specifications according to the CBM-ToF requirements are a very high time resolution of better than 25 ps and a double hit resolution of less than 5 ns. The TDC has to cope with an event rate up to 100 kHz per channel. The time core architecture is based on a delay lock loop followed by a clock driven hit register. For the event handling derandomisation units adapted from FiFo´s are implemented and the readout is controlled by a token ring structure. The serialized data transmission could cover different event types like data, error or synchronisation events. The ASIC submitted in October 2008 is shown in Fig. 5.