Idea for an OpenSource Soldering Iron
This project is just another avr based soldering iron. Since professional equipment is quite pricy and not very complicated this projects takes a good, changeable soldering iron tip like the Weller RT1 and provides all the electronics behind that.
- open hardware (schematic and layout made in Eagle 7.2 freeware license)
- open firmware written in C (not ready to use right now)
- fast heatup
- saving and restoring temperature to and from EEPROM
- high-precision op-amp for temperature measurement
- safety measures against overheating and controller crashes
- automatic temperature control (pid controller)
- different temperature scales available (recompiling necessary)
- solder tip rest detection via hall sensor (optional)
- almost all parts are available from the Seeedstudio Open Parts Library
- 5V for logic
- 12V for soldering iron
- ATmega328p controlled
The thermo-voltage signal is amplified by an op-amp with a gain
g = 1 + R1/R2 = 1 + 51k/100 = 511
this signal is converted by ADC0 using Vcc=5V as voltage reference
Solved by a hall sensor connected to ADC2. This sensor is powered by 5V
- arduino uno shield
- Forum discussion + group order coordination Thema: DIY SMD - Lötstation Ersatz für (WELLER)
- original Weller cable
- unfinished project Custom Weller WSM 1 style controller for RT series tips
- Thermoelement im Weller WMRP.
- power MOSFET IRF7424
- Voltage regulator REG1117
- uC ATmega328P
- Quad OP-Amp LM324D
- Single OP-Amp OPA336u
- Solder Tip Weller RT1
- Solder Tip detector Hallsensor unipolar
- hardware version 1.2 is almost ready to be produced
- optimized bill of materials by reducing unnecessary components
- PCB measures 5cm x 5cm
- individual 7-segment displays in use (broader availability)
- I2C is now unused and can be used for additional hardware