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 16

2026-11-04 05:44 PST (2026-11-04T13:44:21Z UTC) · commit 060416b (060416bc280766a98ea6518b3f67351ab07d1931)

ADOPTED

repair6 checkpoint 4 on the Freerouting board: 40 groups connected; first still-isolated groups appear (U4.12/U4.18 +3V3D_CDR, J1.A4 VBUS_RAW) - later sweeps retry them

Nets fully routednot recorded
Pins failednot recorded
Clearance violations13
Unconnected nets44
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

Top

Pass 16 — top

Bottom

Pass 16 — bottom

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