When it comes to home-lab reflow work, there are a lot of ways to get the job done. The easiest thing to do perhaps is to slap a PID controller on an old toaster oven and call it a day. But if your bench space is limited, you might want to put this compact reflow hotplate to work for you.
There are a lot of nice features in [Toby Chui]’s build, not least of which is the heating element. Many DIY reflow hotplates use a PCB heater, where long, thin traces in the board are used as resistive heating elements. This seems like a great idea, but as [Toby] explains in the project video below, even high-temperature FR4 substrate isn’t rated for the kinds of temperatures needed for some reflow profiles. His search for alternatives led him to metal ceramic heaters (MCH), which are commonly found in medical and laboratory applications. The MCH he chose was rated for 20 VDC at 50 watts — perfect for powering with USB-PD.
The heater sits above the main PCB on a Kapton-wrapped MDF frame with a thermistor to close the loop. While it’s not the biggest work surface we’ve seen, it’s a good size for small projects. The microcontroller is a CH552, which we’ve talked about before; aside from that and the IP2721 PD trigger chip needed to get the full 60 watts out of the USB-PD supply, there’s not much else on the main board.
This looks like a nice design, and [Toby] has made all the design files available if you’d like to give it a crack. Of course, you might want to freshen up on USB-PD before diving in, in which case we recommend [Arya]’s USB-PD primer.
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