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A high frequency multi-phase clock generator circuit with a 6b phase rotator is presented for multi-phase wireline receivers. Multi-phase injection is used to efficiently generate and rotate 8 clock phases. Unlike prior rotator-based work, this work does not use time modulation, reducing the resulting deterministic jitter. A model is presented to study the nonlinearity introduced by the technique. The proposed 17 GHz circuit was implemented in the Intel 16 process and consumes 33 mW. The measured RMS jitter is $$\mathbf{9 8} \mathrm{fs}$$, and the measured DNLpp and INLpp are 1.26 and 4.05 LSB respectively.
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This content will become publicly available on January 1, 2026
Design Techniques for a Multi-Phase Injection-Based Eight-Phase 17-GHz Clock Generator for Multi-Phase Wireline Receivers
Clock generation for high-speed wireline receivers must provide multiple clock phases with high-resolution rotation. To address this, an 8-phase 17 GHz clock generation circuit with built-in 6b rotation is presented. Multi-phase injection is used to perform reference-side phase rotation to efficiently generate and rotate eight clock phases. The injection method is analyzed with a model to study the introduced nonlinearity, and the effect of the injection strength is discussed. Designed by using BAG3++ for layout-aware design optimization, the proposed circuit achieves 98 fs RMS jitter and a measured DNLpp and INLpp of 1.26 and 4.05 LSB respectively, while consuming 33 mW.
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- Award ID(s):
- 2148021
- PAR ID:
- 10630710
- Editor(s):
- NA
- Publisher / Repository:
- IEEE Transactions on Circuits and Systems I: Regular Papers ( Early Access )
- Date Published:
- Journal Name:
- IEEE Transactions on Circuits and Systems I: Regular Papers
- ISSN:
- 1549-8328
- Page Range / eLocation ID:
- 1 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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