Soldering Iron Driver design overview
From DP
Prototype PCBs are available in the free PCB drawer.
You can get a [project for $20], including worldwide shipping.
The Soldering Iron Controller was designed by Arhi (Bogdan Kecman) and shared under public domain in our forums. With his consent we developed our PTH version 1.5 based on the 3rd generation of his driver.
From the get go the Soldering Iron Driver was conceived to drive Hakko 900M (clones) and Solomon irons. As an added bonus it was discovered Weller PES51 irons were compatible as well.
The key to this universal design is the analog front-end which is capable of reading both Thermocouple and PTC temperature sensors. The SID features:
- Compatible with any PTC or TC soldering iron.
- PID temperature control.
- USB data transfer, and firmware update.
- UART data transfer.
- HD44780 2x16 character LCD.
- external NTC temperature sensor, for calibration and better cold junction compensation of TC type sensors.
- Low noise, zero crossing AC heater control.
Contents |
Overview
- History
Soldering Iron Driver works by using PID calculations to maintain the soldering iron tip at a constant pre-set temperature. This is accomplished usurping the analog front end to convert the sensor value into a 0-5V range which corresponds to 0-500 degrees C.
From there the microcontroller uses and internal ADC to read that value. It is then run through a PID algorithm to calculate the power that is needed to supply to the heater to achieve or maintain the preset temperature.
The LCD and buttons are uses to calibrate, and set the wanted tip temperature, as well as to display the current tip temperature.
Hardware
Click for a full size schematic image. Schematic and PCB were designed with the freeware version of Cadsoft Eagle, download the latest project files from our Google Code project page.
Microcontroller section
- Microcontroller
- Power and decoupling
- Oscillator
- Programming and reset support
- LEDs
Analog Front-end
Power Supply
Heater Control
LCD
Connecters
PCB
We used the freeware version of Cadsoft Eagle to make the schematic and PCB. Download the latest designs and firmware from the project Google Code page.
- PCB and placement notes
- soldering advise
Partslist
Click for a full size placement image.
| heading | heading |
|---|---|
| cell | cell |
| cell | cell |
Firmware
The firmware is written in C and compiled with the free Microchip C18 compiler. You can download the latest files from our Google Code project page.
- Operating modes
- extra software required
We used the Microchip USB stack to run the 18F2550 as a virtual serial port. Microchip's code is open but not redistributable. If you want to compile the source, download the stack from Microchip, then drag the source code into the install directory. See the detailed instructions in the PIC compiler how-to.
.inf installation
The virtual serial port (CDC) is an open standard, it should work on any modern operating system.
You don't need a driver, but you will need a .inf file to tell Windows how to use the device. A suitable .inf is included in the project archive.
Commands
Bootloader
Source and license
Taking it further
Here's some ideas for the future:
- List
We'll post the most recent firmware updates on our blog. You can also join the discussion in the [forum].
Get one!
You can [get one for $00], including worldwide shipping.
Your purchases at Seeed Studio keep the open source project coming, we sincerely appreciate your support!