09-13-2016, 05:52 PM
(09-13-2016, 10:08 AM)DonFL Wrote:(09-13-2016, 09:42 AM)tllim Wrote: Our currently lead on this investigation is toward the power quality that RTL8211 received, namely small voltage ripping wave on the VDD and AVDD line. It seems that certain RTL8211 chip sensitive to this voltage noise. We have testing this theory on the other vendor board and initial results seems works well.
We are collecting more GbE affected Pine A64+ boards and our hardware engineering team are focusing into this path. The focus point is on one inductor (ferrite bead) at one of the VDD power line to RTL8211 chip.
P/S: Appreciate Marcus and Tom kaiser effort on this finding.
Regards,
TL Lim
Is the VDD and AVD issue that TL mentions the same as the VDD33 concern that tkaiser had discussed as a possible factor?
We are looking onto three areas, VDD33, AVDD33, and VDD10. This finding close to tkaiser discussion at Sunxi IRC but pin point to ferrite bead is from the other board that suffer on sma e issue. I have recently released the Pine A64+ 2GB schematic at Pine64 wiki page so taht interest parties can explore further.