KiCad PCB revision + ESP32 firmware update for wireless battery monitor (2 boards)

We have a working 2-board wireless battery monitoring system and need an experienced hardware engineer to complete a design revision (rev-B) and production files.

EXISTING SYSTEM (all files provided, KiCad + Arduino/ESP-IDF source):
- Transmitter PCB: ESP32, 2x ADS1115 (16-bit ADC) reading 4S/5S/6S lithium cell voltages via divider network, 3 relay outputs, XL1509 buck + LM1117 3.3V LDO. Powered directly from the battery pack (max 16.8V).
- Receiver PCB: ESP32 + 3.5" ILI9481/ILI9488 TFT, receives data via ESP-NOW.
- Firmware for both boards is working (cell readings, two-point calibration, ESP-NOW, display UI).

SCOPE OF WORK:
1. Review the existing KiCad project and firmware.
2. Transmitter rev-B design changes:
- Add proper input protection: TVS, input fuse / overcurrent protection, inrush/filtering ahead of the buck converter (battery is hot-plugged in the field)
- Add TMP102 temperature sensor on the existing I2C bus (address must not clash with ADS1115s at 0x48/0x49)
- Keep JST battery connector; move USB connector 5mm outward
3. Generate production files: Gerbers, BOM (LCSC/JLC-available parts), pick-and-place with correct rotations, schematic PDF.
4. Firmware update: TMP102 reading, fan relay ON above 40C with hysteresis, temperature shown on receiver display.
5. Test firmware on rev-B sample boards (boards will be shipped to you) and provide a test video.

REQUIREMENTS:
- Strong KiCad experience with power input protection design
- ESP32 + I2C firmware experience
- Must be able to do SMD soldering/rework yourself, and own a current-limited bench power supply and multimeter

IN YOUR PROPOSAL, PLEASE ANSWER:
1. For a 16.8V max battery input feeding a buck converter rated 40V input, which TVS would you choose and why?
2. Share a KiCad board you designed with input protection.
3. Your timeline for steps 1-4.

Milestone-based payment. Proposals without answers to the questions will not be considered.

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來源：Freelancer.com | 出價次數：3 | 剩餘時間：6 日 | 專案類型：固定預算