USB-C Temperature and Humidity Sensor Design
Thought for 12 sec
Work done
- Updated the project description to reflect the low-power USB-C environmental and biosensor node requirements.
- Added and wired the major schematic blocks: J1 USB-C input, U5 protected 5V entry, U4 3.3V regulation, U1 ESP32-C3 Wi-Fi/BLE module, U2 temperature/humidity sensor, U3 EEG AFE, IC1 PPG sensor, plus external interfaces J2 and J3.
- Implemented USB-C sink behavior with 5.1 kΩ CC pull-downs on R1 and R2, VBUS decoupling, ESD protection on D1, and protected input distribution through U5.
- Created the main interconnects for power, I2C, SPI, reset/enable, EEG channels, and PPG interrupt signaling.
- Initialized the PCB layout as a 60 mm x 45 mm rounded rectangle with a Standard 4 Layer stackup and basic board-level rules.
Success criteria review
- ✅ Project description now reflects USB-C power, protection intent, Wi-Fi/BLE, environmental sensing, Bluetooth syncing support, and EEG/PPG interfacing.
- ✅ Schematic now includes the major requested functional blocks and core interconnections for power, MCU, sensor, and biosignal interfaces.
- ✅ Layout has been created and prepared with a 4-layer stackup and board rules for further review and placement.
- ❌ The schematic still has cleanup items on floating or reserved pins, and some biosensor/reference nets remain first-pass placeholders rather than fully production-ready analog circuitry.
- ❌ The current layout outline is smaller than the full component spread, so final placement and routing readiness still need one more pass.
Next steps
I can next clean up the remaining floating pins, replace generic passives with production MPNs where needed, and resize the layout so the board is truly ready for placement and routing.
Add a digital temp/humidity sensor plus EEG and PPG interface blocks to the schematic. Review everything. Make sure it works for hydrophone testing, make sure the emitter is going to work in the transducer as well.
Thought for 1 min 40 sec
You want the current node updated so the temp/humidity, EEG, and PPG blocks are completed and reviewed, with hydrophone/transducer support folded in if it belongs on this board.
- I’ve built the plan.
- It covers sensor-block completion, low-noise integration review, and the acoustic subsystem decision point that changes the architecture significantly
Click Start on the plan bar to run it.
Check USB_CC2 routing
Keep hydrophone analog separate
Run full ERC/DRC
