SR and PPI Jitter Budget Review Comment 162

SR and PPI Jitter Budget Review Comment 162John Petrilla, Avago TechnologiesJune 2009Presentation Overview• Amended Comment 162 & Proposed Remedy• Issue: Efficacy of J2 & J9 for limiting TJ(BER = 1E-12)• Conclusions• Analysis:– Jitter distribution review• Gaussian (G)• Truncated Gaussian (TG)• Sinusoidal (SJ)• Dual-Dirac (dDJ)– J2, J9 and TJ dependence on RJ - DJ combinationsSan Francisco 2009 SR & PPI Jiter Budget Review - Comment 162 2Amended Comment 162 and Proposed RemedyComment (Type T): In Table 86A-3 (also 86A-4) the limits for J2 (0.46) and J9 (0.63) for some reasonable combinations of jitter will permit TJ (at BER = 1E-12) to exceed 0.70 UI which was not intended when these J2 and J9 limits were established. Unfortunately, a similar situation occurred at TP1 and, consequently without some relief at TP1, relief at TP4 is limited. However, it appears that J9 can be tightened from 0.63 UI to 0.62 UI. See petrilla_01_0709 for discussion. Further review of the receiver (sub-clause 86.7.3, page 280, Table 86-8) reveals the conditions for the stressed receiver sensitivity test generate an unneeded and undesirable over-stress condition. The choice of values for J2 (0.35 UI) and J9 (0.47) permit TJ (BER+1E-12) to reach 0.496 UI, higher than the expected 0.485 UI. Also, the vertical eye closure penalty (VECP) value (2 dB) is larger than that calculated (1.9 dB) for updated SR and PPI conditions. These are partly due to misunderstanding ...