GBT20, a 20.48 Gbps PAM4 optical transmitter module for particle physics experiments

Abstract We present a pluggable radiation-tolerant 4-level Pulse-Amplitude-Modulation (PAM4) optical transmitter module called GBT20 (Giga-Bit Transmitter at 20 Gbps) for particle-physics experiments. has an OSFP or firefly connector to input 16 bit data each 1.28 Gbps. The drives VCSEL die with LC lens TOSA and interfaces fiber standard connector. minimum module, including the host connector, occupies 41 mm × 13 6 mm. At 20.48 Gbps, Dispersion Eye Closure Quaternary (TDECQ) is around 0.7 dB. power consumption 164 mW in low-power mode. SEE cross-section below 7.5 10 −14 cm 2 . No significant performance degrades after TID of 5.4 kGy.