INA219 Current Measurement Audit
- Q2:D -> VIN_FUSED
- Q2:S -> VIN_PROTECTED
- Q2:G -> VIN_GATE
- D6:K -> VIN_PROTECTED
- D6:A -> VIN_GATE
- R5 from VIN_GATE to GND
- R6 between VIN_PROTECTED and VIN_GATE
- Review the PCB layout only around Q2, F2, D3, D6, R5, R6, C7, FB2, and the nets VIN_RAW, VIN_FUSED, VIN_PROTECTED, VIN_GATE, GND.
- Remove any stale traces caused by the Q2 source/drain swap.
- Reroute Q2 input-protection traces so the physical PCB matches the corrected schematic.
- Keep the current protection sequence: J1 P1 -> F2 -> VIN_FUSED -> Q2 -> VIN_PROTECTED -> D3/C7/FB2 -> VIN_FILTERED.
- Keep Q2, D3, C7, and FB2 routing reasonably short and direct.
- Do not modify ESP32, relay, INA219, buck output, RELAY_OUT, or dry-contact nets.
- Do not perform a full board redesign yet.
- Run DRC.
- Confirm there are no airwires in the Q2/F2/D3/D6/R5/R6/C7/FB2 input-protection area.
- Confirm there are no dangling traces in the Q2 input-protection area.
- Report the exact physical routing path from J1 P1 to U1 VIN after the fix.
- Confirm again that reverse-polarity input cannot energize VIN_PROTECTED or 5V.
Started implementing a plan
#Goal
- Audit and fix the PCB routing around the Q2 input reverse-polarity protection stage based on the schematic correction, concentrating only on Q2, F2, D3, D6, R5, R6, C7, FB2 and nets VIN_RAW, VIN_FUSED, VIN_PROTECTED, VIN_GATE, and GND. The goal is to remove stale traces from the Q2 source/drain reversal and reroute the protected input path so that it physically follows the path: J1 P1 -> F2 -> VIN_FUSED -> Q2 -> VIN_PROTECTED -> D3/C7/FB2 -> VIN_FILTERED, while ensuring the routing remains short and direct without impacting other nets (ESP32, relay, INA219, buck output, RELAY_OUT, dry-contact).
#Implementation plan
1. **Audit and Cleanup**
1. Inspect the existing PCB layout in the Q2 input reverse-polarity area to identify stale traces and artifacts from the old Q2 source/drain swap.
2. Remove or sever stale traces that connect the Q2 source/drain paths from previous routing.
2. **Reroute Input-Protected Path**
1. Reroute the protected input path to ensure the physical trace follows: J1 P1 -> F2 -> VIN_FUSED -> Q2 -> VIN_PROTECTED -> D3/C7/FB2 -> VIN_FILTERED.
2. Maintain a short and direct routing while connecting the nets correctly.
3. Preserve the integrity of other nets and components including ESP32, relay, INA219, buck output, RELAY_OUT, and dry-contact.
3. **DRC Verification and Reporting**
1. Run a targeted Design Rule Check (DRC) focusing on the audited area to ensure clearance and connectivity rules are met.
2. Document and report the exact physical routing path and confirm that the reverse-polarity protection works as intended (i.e. reverse-polarity does not pass through VIN_PROTECTED into the remainder of the circuit).
#Success criteria
- All stale traces from the Q2 source/drain swap are removed without affecting other board areas.
- The physical routing path exactly follows J1 P1 -> F2 -> VIN_FUSED -> Q2 -> VIN_PROTECTED -> D3/C7/FB2 -> VIN_FILTERED, ensuring short and direct routing.
- DRC reports no violations in the scoped area and confirm reverse-polarity behavior as expected.
- The protected input path prevents undesired conduction during reverse polarity events.
Task unable to complete.
2:13
- Audited the scoped Q2 input-protection area and verified the corrected schematic connectivity.
- DRC still reports scoped layout problems: VIN_FUSED airwire between
F2:P2andQ2:D, VIN_PROTECTED airwires involvingQ2:S,D6:K, andR6:P2, plus stale/dangling trace remnants and an overlap atQ2:D. - Created the detailed status file: Q2 Input Protection Routing Remediation Status.
- ❌ Stale traces were identified but not removed in this run.
- ❌ The physical path is not yet fully routed as
J1 P1 -> F2 -> VIN_FUSED -> Q2 -> VIN_PROTECTED -> D3/C7/FB2 -> VIN_FILTERED. - ❌ DRC is not clean in the scoped area; airwires/dangling/overlap issues remain.
- ✅ The corrected schematic topology still supports reverse-polarity blocking, but the PCB must be cleaned/rerouted before fabrication.
