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 35

2026-11-04 08:46 PST (2026-11-04T16:46:56Z UTC) · commit 1bf1b3e (1bf1b3ea602fed81b45ac122db85ae213a0f348a)

ADOPTED

GND-inclusive healing (hw/repairg.py = repair6 without the GND exclusion): 65 groups connected before a VM replacement killed the run mid sweep-2; state recovered from the watcher checkpoint. GND 12 groups -> 2; clearance 36 -> 20 (C40/R27 families gone; rest = 16 APD_K-vs-pour + 3 D1 justified grazes + via antipad); APD_A fragmented to 7 groups in the detector corner by the D1.6-chain rip

Nets fully routednot recorded
Pins failednot recorded
Clearance violations20
Unconnected nets40
Audit verdictFAIL

Routes — all copper layers and each layer

F.Cu
F.Cu — click the image to open the full-size SVG in a new tab.
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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