Migration Reconstruction and Safety Review

mansingh33

mansingh33

flux

I can’t run auto-layout right now because AI execution is unavailable: the account has no available ACUs. I’m not able to call the placement/routing tools until ACUs are available again.
What has been completed so far:
  • Recreated and verified the main schematic documentation set.
  • Reconstructed/verified these phase 3 schematic blocks:
    • Protected 5S battery input/protection block.
    • Raspberry Pi 5.1 V branch.
    • LCD 5.0 V branch.
    • 12 V KVM branch.
  • Preserved intentional no-connects and warnings, including MOD1 VCC as the known TPSM63606 ERC false positive.
  • No PCB layout work has been started or validated.
What remains before auto-layout is appropriate:
  • Finish schematic reconstruction for the USB-C PD charge/interlock subsystem and any remaining blocks.
  • Reconcile the expected 44 nets vs current 43 nets.
  • Run full ERC and resolve/document all remaining issues.
  • Then proceed to PCB placement first, followed by routing. Current state likely needs both placement and routing, but final layout should wait until schematic/ERC reconciliation is complete.
Find net mismatch
Finish USB-C subsystem
List remaining blocks
Review BOM issues

Refine this doc
Ask about this doc
PCB Assembly Notes
Date restored: 2026-07-24
Status: Assembly guidance only / not fabrication-ready
Assembly Status
The original project evidence reports substantial schematic/document work, but the current migrated target has not yet reconstructed the schematic or PCB layout. This file preserves assembly constraints and warnings from source evidence.
The following were not finished in the source evidence and are not complete in the current target:
  • Final 190 mm × 125 mm board outline.
  • Final mounting and strain-relief holes.
  • Final component placement.
  • High-current routing.
  • Copper planes.
  • Thermal validation.
  • Final charger selection and footprint.
  • Final balance-harness or integrated-BMS implementation.
  • Final ERC/DRC closure.
  • Manufacturing Gerbers.
  • Pick-and-place data.
  • Fabrication approval.
Do not misrepresent layout exports, layer drawings, or 3D models as proof that these tasks passed review.
Board and Stackup Intent
  • Target outline: 190 mm × 125 mm, rounded corners, Echo Show 8-class footprint.
  • Four main mounting holes.
  • Additional module-retention holes.
  • XT60 and cable strain-relief holes.
  • Keepouts for connectors, wiring, fuse replacement, and switch access.
  • Edge-mounted user connectors where practical.
  • Pololu modules retained by required mounting hardware.
  • Intended four-layer stack:
    • L1: components and high-current routing.
    • L2: continuous ground plane.
    • L3: power distribution and low-current signals.
    • L4: secondary routing and ground copper.
    • Outer copper: 2 oz.
    • Inner copper: 1 oz.
High-Current and Thermal Assembly Notes
  • Use wide copper pours/planes for battery, ground, 5.1 V, 5 V, and 12 V current paths.
  • Use thermal vias and copper areas according to component datasheets.
  • Keep the charger thermally separated from output regulators.
  • Preserve uninterrupted ground plane wherever practical.
  • Inspect every high-current connector, fuse holder, and module pin for solder quality.
  • Perform current-density, voltage-drop, and thermal review before release.
Resolved / Evidence-Based Component Notes
  • MOD1: TI TPSM63606RDLR for 5.1 V rail; follow TI land pattern, thermal pad, via array, capacitor placement, and SW-node requirements.
  • MOD2: Pololu D36V28F5, item 3782; official mechanics 17.8 × 20.3 mm and two 2.2 mm M2 retention holes documented.
  • MOD3: Pololu D36V28F12, item 3786; official Pololu dimension/drill guide must be followed.
  • J4: Tensility 54-00127, 5.5 × 2.1 mm right-angle THT barrel connector, 48 V / 6 A, center-positive mapping.
  • SW1: TE Connectivity 282837-2 terminal interface for an off-board maintained SPST switch; actual switch must be rated ≥5 A at ≥30 VDC.
  • Fuse holders: Littelfuse 64900001039 5×20 mm PCB holders; fuse elements remain application-specific.
  • USB-C receptacles: USB4235-03-C_REVA evidence; J2/J3 source-only, J5 charge-only/sink-only.
  • Test points: Keystone 5002 evidence.
DNI / TBD / Blocked Assembly Items
  • R15: DNI/TBD until PD_20V_OK polarity/level is verified.
  • C16/C18/C20: DNI/TBD charger bulk capacitors pending selected module datasheets.
  • MOD4/MOD5/MOD6: exact modules, connectors, pinouts, footprints, mount points, and keepouts remain release blockers.
  • Optional 2 A charge mode: disabled/DNI until pack, BMS, charger, fuse, and thermal approval.
  • Balance harness: not assembled or connected to carrier PCB.
Fuse Assembly Notes
  • F1: main input, initially targeted near 5 A; final DC interrupt rating and time-current curve required.
  • F2: Pi branch, 3.15 A time-lag provisional.
  • F3: LCD branch, 2 A provisional.
  • F4: KVM branch, 1 A provisional.
  • F5: charge path, 2.5 A provisional.
Fuse values are not automatically approved. Recalculate after final loads, wire gauge, connectors, module ratings, fault current, and measured inrush are known.
USB-C Assembly Notes
  • J2/J3: source-only outputs with passive Rp; no USB-PD and no data.
  • J5: charge-only/sink-only; no source/OTG and no Rp.
  • J5 D+/D−/SBU intentionally no-connect.
  • Label J5 clearly as charge-only.
  • A 5 V-only source or failed PD negotiation must not enable charging.
Battery Harness and Connection Sequence Warning
  • Taps must be mapped by DMM, never by wire color.
  • Seller photos and diagrams do not prove balance-pin order.
  • Separate XT60 and sense plugs are prototype-only unless connection sequence is engineered.
  • A production removable pack should keep its BMS attached or use an interlocked combined connector.
  • If a future TI BMS implementation is added, follow TI-required connection sequence such as BATT− first, then other cell connections, per the relevant datasheet/EVM documentation.
Inspection Notes Before Power
  1. Confirm all fuses and fuse holders are installed/omitted as intended.
  2. Confirm DNI/TBD parts are not accidentally populated.
  3. Confirm USB-C source and sink ports are not swapped.
  4. Confirm barrel connector center-positive mapping.
  5. Confirm switch-loop wiring.
  6. Confirm no copper/connector feature connects to an unverified balance harness.
  7. Confirm NTC connector is physically separate from balance connector.
  8. Confirm all high-current solder joints and mechanical retention points.
Source Gaps Preserved
The source evidence did not provide complete original full-text content for this file. This reconstructed version preserves the assembly constraints, resolved part decisions, and warnings present in the migration bundle and parsed .flx evidence, but it must be reviewed against any future recovered native project file content.

  • Assembly Status

  • Board and Stackup Intent

  • High-Current and Thermal Assembly Notes

  • Resolved / Evidence-Based Component Notes

  • DNI / TBD / Blocked Assembly Items

  • Fuse Assembly Notes

  • USB-C Assembly Notes

  • Battery Harness and Connection Sequence Warning

  • Inspection Notes Before Power

  • Source Gaps Preserved

Protected Module-Based 5S Power Distribution Board thumbnail
Carrier PCB for a removable 5S 18.5 V 4000 mAh LiPo-powered Raspberry Pi 400 workstation. Provides protected input, independent low-voltage cutoff, dedicated fused 5.1 V USB-C Pi output, 5 V USB-C LCD output, 12 V center-positive KVM output, cooling-fan power, and a safety-interlocked USB-C PD 5S charging path. This project remains under engineering review and is not fabrication-ready.

Properties

Properties describe core aspects of the project.

Pricing & Availability

Distributor

Qty 1

Arrow

$22.31–$6,571.44

Digi-Key

$6.14

HQonline

$7.17

LCSC

$35.34–$257.84

Mouser

$24.15–$103.35

TME

$0.28

Verical

$8.67–$166.92

Controls