TID characterization of a serial transmitter core for high-energy physics experiments

Purpose Serial transmitters are essential and commonly used for data transmission in pixelated detector-readout electronics and in common data links. The transmitters developed in application-specific integrated circuits (ASIC) are required for radiation tolerance in applications for particle physics experiments. This paper presents radiation tests of total ionizing dose (TID) on a serial transmitter core manufactured by a deep submicron technology.
Methods The serial transmitter core comprises a ring-oscillator-based phase-locked loop for the high-frequency clock generation, a divider for clock synchronization, and a serializer for data serialization. The transmitter accepts a reference clock from 7 to 52 MHz and parallel data of 40 bits. It produces a serial data stream ranging from 0.7 to 5.2 Gbps. Large-size transistors are chosen to mitigate radiation induced effects.
Results and Conclusion The functional tests of the serial transmitter agree with the ASIC design simulation. At 4 Gbps, the total jitter in the serial data stream is around 64 ps, the random jitter is approximately 1.4 ps, and the total power consumption of the ASIC is about 151.2 mW. X-ray tests indicate that the circuit is capable of withstanding a TID up to 43.1 Mrad (Si) at a dose rate of 1.4 Mrad(Si)/h. High dose rates can significantly affect sensitive circuits, such as the bias generator of the low-voltage differential signaling driver, potentially leading to damage.