This device is trade-off for hobby use, if you need to assemble small PCBs from time to time. Of cause, it's not as good as reflow oven or bga reball station, but it's MUCH smaller.
This project is not "new", and inspired by others like this one. Idea is to make device more useable and easy to repeat. That includes:
- Simple assembly
- More convenient power source
- Nice GUI
Components and assembly
After searching aliexpress, found 50*50mm MCH heaters - maximal suitable of available in MCH segment. Plate temperature is not equal everywhere, so we should have about 30*30mm of working area. Not much, but not bad too. If you order boards with modern components, a lot of ones will fit such size with ease.
Another point is to use PCB as mounting frame - put MCH & touchscreen on top, and everyting else on bottom. That requires experimenting with thermal insulation, but that's doable.
With preliminary estimates, total size will be 130*70mm, 20mm height. Good enough to pretend on been small and convenient tool. You can see progress of PCB rework on EasyEDA page.
Initially schematic was drawn for 220v power with small HLK-05 modules for CPU and triac control for MCH. But later i discovered USB-PD and decided to use it instead. Required power is 30-40W, easy to get from medium chargers. Result will be more compact and more safe.
This caused whole project to freeze for a notable time. I was searching open source libs, suitable to build advanced scenes and animations on resource constrained MCU-s. As a result - instead of doing my own projects, i participated in lvgl development. New version does nice font rendering and very soon will do subpixel smoothing (it's already in dev branch).
But I'm finally back, and ready to move forward. May be you've seen dispenser project, been done in parallel with this one. It also uses lvgl and i already posted prototyped interface there.
Let's go! In next log entry will share results of MCH thermal insulation, when been mounted on PCB.