This general-purpose controller features:
- Wheatstone Bridge front-end
- New Texas Instruments INA823 instrumentation amplifier
- Accurate REF2030 1.5/3V dual reference voltage source (<0.05%, 1.5 ppm/°C typ.)
- 48-pin STM32G0B1CE 512kB Flash/144 kB RAM MPU
- Popular Waveshare 18179 128x64 1.3" OLED display
- Rotary encoder and I2C EEPROM
- STLINK-V3 mini and STLINK-V2 debug connectors (Segger J-Link mini supported)
- Small dimensions - only 85x50mm
- USB socket, can be used as a power source
- Real Time Clock (RTC) with quartz crystal oscillator
- Miniature battery or supercapacitor for RTC and memory backup
- Opto-isolated serial port (RX/TX)
- I2C port
- Two buffered DACs
- Larger Waveshare 14747 128x128 1.5" RGB OLED display
- Two potentiometers for fine-tuning (gain and zero)
The device has been designed to be easily configured - e.g. here as a Weller WSP80 station/controller powered from a standard 30V/5A bench power supply. Controller can be easily configured to work with any NPT/PPT thermistor or a thermo-couple.
I have built this universal controller to test some design concepts and have used it intensively for over a year as a Weller WSP80 soldering iron controller powered from a standard 30V/5A bench power supply.
Published schematic includes probably the final 3rd version, slightly improved over what is presented on the pictures (2nd version).
For complete project documentation see this GitHub repo.