SKR Mini E3 V2.0 Thermistor Expander by Timmit99

Add two thermistor inputs to a BTT SKR Mini E3 using the TFT header. This Timmit99 / Voron-Hardware expander gives SKR Mini E3 V1.2, V2.0, and V3.0 boards two additional temperature-sensor channels for Klipper builds without giving up the EXP1 or SPI display headers.

Why use this board

• Adds two extra thermistor channels for chamber, electronics-bay, exhaust, or spare temperature monitoring.
• Uses the SKR Mini E3 TFT header: T0 on TX2 / PA2 and T1 on RX2 / PA3.
• Designed to pair cleanly with the SKR Mini v1/v2 screen adaptor by Timmit99 when the EXP1 and SPI headers are already committed to a display.
• Works with Klipper's standard [temperature_sensor] configuration; boards with 4.7K pullups use Klipper's default pullup value.

Specifications

• Project: Voron-Hardware SKR-Mini TFT Thermistor Board by Timmit99.
• Compatible control boards: BIGTREETECH SKR Mini E3 V1.2, V2.0, and V3.0.
• Thermistor inputs: two channels, T0 and T1.
• Pin mapping: T0 = TX2 / PA2; T1 = RX2 / PA3.
• Pullup: standard design uses 4.7K pullups, matching Klipper's default.
• Connectors: two 2-pin JST-XH thermistor sockets, 5-pin 2.54mm Dupont TFT-header connector, and 1-pin 3.3V jumper pin.
• Included: assembled thermistor expander PCB.

Fitment and setup notes

• Use it when your SKR Mini E3 build needs more temperature inputs than the mainboard provides, especially Voron V0 / Ender-style Klipper conversions with chamber or electronics-bay sensing.
• Pair it with a 100K NTC 3950 thermistor or other Klipper-supported thermistor as needed; thermistors are not included with this board.
• Install with the board on the TFT header and run the single 3.3V jumper to the SKR Mini E3 SWD 3.3V pin per the Voron-Hardware installation notes.

Klipper gotcha

Check the resistor markings on your board before final configuration. If the resistor is marked 4701, use Klipper's default pullup. If it is marked 1001, add pullup_resistor: 1000 in that [temperature_sensor] section.

[temperature_sensor chamber]
sensor_type: Generic 3950
sensor_pin: PA2
# pullup_resistor: 1000  # only if the board resistor is marked 1001

What it is not

• Not a standalone MCU, CAN board, heater expander, fan expander, or RTD amplifier.
• Not a replacement for the broader Klipper Expander by Timmit99 if you also need MOSFET outputs or a separate Klipper MCU.

“Works on the SKR Mini E3 V3.0 as well. Currently using this successfully on my V0.”