Battery-Powered Fan Controller Design
Worked for 1 min 25 sec
I found low-cost battery options: TP4056 charger, JST-PH LiPo connector, a buck-boost 3.3 V rail for the ESP32, and an optional 5 V boost stage for the fan if the fan must run from the battery.
Worked for 7 mins 41 sec
Implemented the first-pass schematic for a low-cost rechargeable LiPo thermocouple fan controller with ESP32-C6 BLE/Wi‑Fi, MAX31855 K-type thermocouple input, TP4056 USB-C charging, 3.3 V buck-boost regulation, and PWM fan drive with optional 5 V boost. I also added project docs: spec, bring-up plan, firmware notes, and regulatory/safety notes. Initial ERC-style checks came back with no open warnings/errors in the checked categories.
Open items:
- Confirm fan voltage/current and whether it must run fully from the internal battery.
- Confirm desired runtime and battery capacity.
- Decide whether phone-only UI is enough or if you want a small display.
- Confirm thermocouple connector style: screw terminal vs proper miniature thermocouple jack.
Suggested next steps:
- Pick the actual fan/blower and battery capacity.
- Add battery voltage measurement so the phone UI can show charge level.
- Move to PCB layout with antenna clearance and charger/boost thermal placement.
- Add a basic ESP32 firmware skeleton for BLE/Wi‑Fi provisioning, thermocouple readout, and fan PID control.
Set fan and battery
Use 5V blower
Add battery sensing
Start PCB layout
Check BOM cost
Phone-only UI
Refine this doc
Ask about this doc
Firmware Notes
MCU
ESP32-C6-WROOM-1-N8 provides BLE and Wi‑Fi phone connectivity without a separate radio.
Pin Map
Table
| Function | ESP32-C6 Pin | Net |
|---|---|---|
| Thermocouple SCK | IO6 | TC_SCK |
| Thermocouple MISO | IO7 | TC_MISO |
| Thermocouple CS | IO10 | TC_CS |
| Fan PWM gate drive | IO22 | FAN_PWM |
| Optional fan boost enable | IO23 | FAN_BOOST_EN |
| Status LED | IO20 | STATUS_LED |
| User button | IO21 | USER_BUTTON |
Firmware Behavior
- Use BLE provisioning or Wi‑Fi soft AP for phone setup.
- Read MAX31855 periodically and filter temperature.
- Use a PID or simple proportional control loop for fan PWM.
- Disable fan boost when idle to save battery.
- Report battery state in firmware after a future VBAT divider/ADC is added.
Open Firmware Item
The current schematic does not yet include a VBAT measurement divider. Add one if phone UI should show battery percentage.
MCU
Pin Map
Firmware Behavior
Open Firmware Item
