摘要(英) |
In this thesis, a novel timing and data recovery algorithm for high-speed serial link is proposed. Instead of using the traditional PLL, we use the phase picking architecture. In our design, a 5X oversampling using multi-phase clocks are used to obtain the data information. And our purpose is to find the data transition position and pick the optimum phase for data sampling according to such information.
The transition point may move due to static phase error or jitters (dynamic phase error due to noise). These non-ideal effects cause the reduction of SNR and timing margin. So, the system should detect the phase errors and output a recovery clock to track it.
First, a majority voter chain is applied to enhance the data reliability. Then the transition position of each bit can be detected by XOR. The transition information are accumulated in the confidence counter and the machine will decide that whether the sampling phase should change. By such recovery mechanism, the sampling phase is fixed at the central point of data. Finally, according to the phase selected, three sample values are processed by a majority voter to obtain the recovered data.
Besides, we also develop an analysis method for bit error rate prediction according to the different system parameters. By the analysis results, one can decide the system parameters depend on the design specifications instead of iterations.
Finally, we use Xilinx FPGA for function simulation of the recovery system. Moreover, a bit error measurement modules are built in to test the system performance. |
參考文獻 |
[1] John Poulton and William J. Dally,” A tracking clock recovery receiver for 4Gb/s signaling,” IEEE Micro, p.25-p.27, Jan-Feb, 1998.
[2] Alen Fiedler etal, “ A 1.0625Gbps transceiver with 2X presampling and transmit pre-emphasis, “ ISSCC Conference, Session 15, p.238-p.239, Feb 1997.
[3] Ramin Farjad-Rad, Chih-Kong Ken Yang, Mark Horowitz and Thomas Lee, “ A 0.3um CMOS 8-Gb/s 4-PAM Serial Link Transceiver,”1999 Symposia on Technology and Circuits, Session 5, High Speed Link II.
[4] C.-K. Yang and M. Horowitz, “ A 0.8um CMOS 2.5Gbps oversampling receiver and transmitter for serial links,” IEEE J. Solid-State Circuits, VOL. 31, NO.12, p.2015-p.2023,December, 1996.
[5] Yongsarn Moon and Deog-Kyoon Jeong , “A 1 Gbps Transceiver witg Receiver- End Deskewing Capability using Non-Uniform Tracked Oversampling and a 250- 750MHz Four-Phase DLL,’ 1999 Symposia on Technology and Circuits, Session 5, High Speed Link II.
[6] Kyeongho Lee, Yeshik Shin, Sungjoon Kim, Deog-Kyoon Jeong, Gyudong Kim,
and Victor Da Costa, “1.04GBd Low EMI Digital Video Interface System Using
Small Swing Serial Link Technique,” IEEE J. Solid-State Circuits, VOL. 33, NO.
5, p.816 —p.823, May 1998.
[7] Kyeongho Lee, Sungjoon Kim, Gijung Ahn, and Deog-Kyoon Jeong,” A CMOS
Serial Link for Fully Duplexed Data Communication,” IEEE J. Solid-State
Circuits, VOL 30, NO.4, p.353-p.364, April, 1995.
[8] Sungjoon Kim, Kyeongho Lee, Deog-Kyoon Jeong, David D. Lee, and Andreas G. Nowatzyk,”An 800Mbps Multi-Channel Serial Link with 3X Oversampling,” IEEE Custom Integrated Circuits Conference, p.451-p.454, 1995
[9] Chih-Kong Ken Yang, Ramin Farjad-Rad, and Mark A. Horowitz, “ A 0.5-um
CMOS 4.0-Gbit/s Serial Link Transceiver with Data Recovery Using
Oversampling,” IEEE J. Solid-State Circuits, VOL.33, NO.5, p.713-p.722, May
1998.
[10] Roland E.Best, Phase-Locked Loops, McGraw-Hill, Inc. 2nd edition.
[11] Bernard Sklar, Digital Communications, P T R Prentice Hall, Inc.
[12] Ah-Lyan Yee, Richard Gu, Heng-Chih Lin, Andy Tsong, Richard Prentice, James Tran, “An Intergratable 1-2.5Gbps Low Jitter CMOS Transceiver with Built in Self Test Capability,” 1999 Symposia on Technology and Circuits, Session 5, High Speed Link II. |