PDLVDS-RX — photodiode LVDS receiver

Clean-room receiver for the Miniscope Zero optical uplink: Excelitas C30737LH Si APD → OPA657 TIA → LMH7220 comparator (LVDS out, DAC-set threshold) → ADN2813 CDR → STM32H723 + USB3300 USB-HS. Design target: 50 Mbps line rate, 8b/10b (40 Mbps payload); the paper's mode: 8 Mbps Manchester (16 Mbaud), as transmitted. LT3757 flyback APD bias 150–420 V. USB-C powered; verify on any laptop over USB, no FPGA attached.

Pass 147

2026-11-06 01:30 PST (2026-11-06T09:30:47Z UTC) · commit c12c810 (c12c810d0598c41c254e8324e14742d76b1d499d)

ADOPTED

Heal-stub prune on exp176. 75 stub segments removed over 33 referee-clean rounds (unconnected items 44 in every round); round 33’s single removal split a group (44 -> 45 at the next DRC) and the tool restored the last good board itself – that segment, the last link of a long stub chain, is live copper the contact graph under-models, same family as the excluded GND track; it stays. KiCad DRC referee against the committed exp176 (229/44): violations 229 -> 217, dangling items 30 -> 25, copper_edge_clearance 40 -> 33 (several pruned stubs were also edge violators), clearance 35, shorting 0, unconnected 44 UNCHANGED. Residue unchanged in kind: 4 graph-vetoed bridges + 19 matcher-ambiguous fanout joints (skipped, never guessed) + the excluded GND track + the rolled-back chain link.

Nets fully routednot recorded
Pins failednot recorded
Clearance violations68
Unconnected nets31
Audit verdictFAIL

Routes — all copper layers and each layer

All layers
All layers — click the image to open the full-size SVG in a new tab.
All layersAll layers F.Cu layerF.CuIn1.Cu layerIn1.CuIn2.Cu layerIn2.CuB.Cu layerB.Cu

F.Cu In1.Cu In2.Cu B.Cu

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