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arXiv · 2302.08069

GBT20, a 20.48 Gbps PAM4 Optical Transmitter Module for Particle Physics Experiments

B. Deng·L. Zhang·C. -P. Chao·S. -W. Chen·E. Cruda·D. Gong·S. Hou·G. Huang·X. Huang·C. -Y. Li·C. Liu·T. Liu·E. R. Liu·Q. Sun·X. Sun·G. Wong·J. Ye
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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. GBT20 has an OSFP or firefly connector to input 16-bit data each at 1.28 Gbps. The GBT20 drives a VCSEL die with an LC lens or a VCSEL TOSA and interfaces an optical fiber with a standard LC connector. The minimum module, including the host connector, occupies 41 mm x 13 mm x 6 mm. At 20.48 Gbps, the minimum Transmitter Dispersion Eye Closure Quaternary (TDECQ) is around 0.7 dB. The power consumption is around 164 mW in the low-power mode. The SEE cross-section is below 7.5x10^(-14) cm^2. No significant performance degrades after a TID of 5.4 kGy.

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B. Deng, L. Zhang, C. -P. Chao, S. -W. Chen, E. Cruda, D. Gong, S. Hou, G. Huang, X. Huang, C. -Y. Li, C. Liu, T. Liu, E. R. Liu, Q. Sun, X. Sun, G. Wong, J. Ye. 2023-02-16. GBT20, a 20.48 Gbps PAM4 Optical Transmitter Module for Particle Physics Experiments. https://doi.org/10.1088/1748-0221/18/02/c02065

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