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Topic: Really universal soldering controller (Read 818188 times) previous topic - next topic

Re: Really universal soldering controller

Reply #5430
admaverick, minkok, it's much easier to just implement auxiliary DC supply, rather than messing with values and dropping 30-odd Volts on Q1.
If I was going to redesign the power board to support higher voltage irons, I'd use 12V supply and get rid of Q1 and Q13 circuits all along.
It could be a separate 3W AC-DC supply, like IRM-03-12 or separate 9VAC transformer winding with it's own rectifier and filtering. If you have a toroidal transformer, just wind a turn on top and measure the voltage on it, then wind the remaining.
I totally agrees with you afedorov regarding the auxiliary 12v supply. Unfortunately, per Sparkybg's current design, you have to keep the valley fill circuit near Q1 in order to minimize switching noise around zero crossing. I am planning to do a revamp of Unisolder using STM32 instead of PIC32 and will be all modular design (i.e. you can swap in different power board for different applications while keeping the MCU board).

Re: Really universal soldering controller

Reply #5431
I totally agrees with you afedorov regarding the auxiliary 12v supply. Unfortunately, per Sparkybg's current design, you have to keep the valley fill circuit near Q1 in order to minimize switching noise around zero crossing. I am planning to do a revamp of Unisolder using STM32 instead of PIC32 and will be all modular design (i.e. you can swap in different power board for different applications while keeping the MCU board).
Modular design - good approach, No cables - easy assemble, less noise, place saving, about swapping power boards - big effort ( open the case and so on ). For me, I am impatient even when I need to change the handle! I want just to grab it and to use it

Re: Really universal soldering controller

Reply #5432
Modular design - good approach, No cables - easy assemble, less noise, place saving, about swapping power boards - big effort ( open the case and so on ). For me, I am impatient even when I need to change the handle! I want just to grab it and to use it
Modular Power boards isn't for hot-swapping in my opinion. It is more about Balance between budget and performance needed. (You don't need big expensive 100v+ low Rdson MOSFETs for 210 and 105 handles) Another aspect of modular design is that iron Configuration and Firmware should be separated so that Iron Profiled can be easily trimmed or added to the station, besides MCU board could support up to 2 or even 4 independent heating channels, but you can just install one heating channel.

Re: Really universal soldering controller

Reply #5433
Modular Power boards isn't for hot-swapping in my opinion. It is more about Balance between budget and performance needed. (You don't need big expensive 100v+ low Rdson MOSFETs for 210 and 105 handles) Another aspect of modular design is that iron Configuration and Firmware should be separated so that Iron Profiled can be easily trimmed or added to the station, besides MCU board could support up to 2 or even 4 independent heating channels, but you can just install one heating channel.
I don't want to be critical, but that sounds a bit strange. Let say we have a modular design that consists of a certain count of modules , if you want to separate them for using the low parameters transistors you should use modular power supply boards also (cheap transistors/low voltage power supply ) In that case You could assemble 2 -3 independent soldering stations from your modules. What about the Trf. - it has to support all needed voltages and enough power to support 4 independent tools? Or I have to collect 4 of them?
Isn't that the advantage of Unisolder, on 1 instrument to play many tools and if there is switching board attached to it, to connect them all  the same time and use them 1 by 1

Re: Really universal soldering controller

Reply #5434
I don't want to be critical, but that sounds a bit strange. Let say we have a modular design that consists of a certain count of modules , if you want to separate them for using the low parameters transistors you should use modular power supply boards also (cheap transistors/low voltage power supply ) In that case You could assemble 2 -3 independent soldering stations from your modules. What about the Trf. - it has to support all needed voltages and enough power to support 4 independent tools? Or I have to collect 4 of them?
Isn't that the advantage of Unisolder, on 1 instrument to play many tools and if there is switching board attached to it, to connect them all  the same time and use them 1 by 1
My thoughts are MCU aka Control board (with low noise Buck converter for powering opamps on the power board) remains the same while you can connect different module power board to MCU board. Like one power board dedicated to T470 and other high power irons while another board is optimized for 12v tools (C210 and C105). Power board has nothing to do with supporting different tools, as I said before MCU board holds all iron profiles needed.

Re: Really universal soldering controller

Reply #5435
I don't want to be critical, but that sounds a bit strange. Let say we have a modular design that consists of a certain count of modules , if you want to separate them for using the low parameters transistors you should use modular power supply boards also (cheap transistors/low voltage power supply ) In that case You could assemble 2 -3 independent soldering stations from your modules. What about the Trf. - it has to support all needed voltages and enough power to support 4 independent tools? Or I have to collect 4 of them?
Isn't that the advantage of Unisolder, on 1 instrument to play many tools and if there is switching board attached to it, to connect them all  the same time and use them 1 by 1
You don’t have to hookup 4 power board to the MCU board at the same time. I said UP to 4 independent channels.

Re: Really universal soldering controller

Reply #5436
but will create more noise
It shouldn't cause any problems, there is DC-DC converter after it anyway.
Q5 circuit is 6v, plenty of headroom with 12V input.
Yes, when using separate winding, bridge rectifier and cap is required, a bit ugly, but it won't take much space and will be fairly reliable.

Re: Really universal soldering controller

Reply #5437
I am planning to do a revamp of Unisolder using STM32 instead of PIC32 and will be all modular design (i.e. you can swap in different power board for different applications while keeping the MCU board).
All of us have ideas and want them to become real. I can only advise you to count well the pros and cons. Definitely, it will be not short and easy and will involve resources

Re: Really universal soldering controller

Reply #5438
Yes, when using separate winding, bridge rectifier and cap is required, a bit ugly,
Plus extra stabilization circuit, isn't it ( if not used converter ), the dimension will not be much bigger. :)

Re: Really universal soldering controller

Reply #5439
Plus extra stabilization circuit
What stabilization circuit?
D6,R2,D5,Q1 is removed, Q1 collector-emiter bridged, D5 bridged, aux supply connected to C22. That's all. AC rectifier may be designed as a patch board.
There will be some drop on Q13 circuit, but it should produce enough voltage for lower mosfets, even 8V resulting gate voltage would be enough.


Re: Really universal soldering controller

Reply #5441
If aux supply is 10~15VDC, Q13 also can be removed and bridged, D14 removed and bridged, R19 removed. R20 has a rather large resistance, something like 22~47 Ohms would be enough to suppress driver noise.

Re: Really universal soldering controller

Reply #5442
What stabilization circuit?
D6,R2,D5,Q1 is removed, Q1 collector-emiter bridged, D5 bridged, aux supply connected to C22. That's all. AC rectifier may be designed as a patch board.
There will be some drop on Q13 circuit, but it should produce enough voltage for lower mosfets, even 8V resulting gate voltage would be enough.
D12-C13-R10-ZD1-ZD2-Q5-R9-C12-D11 still need to connect with the 48v (or 24v) supply though.

Re: Really universal soldering controller

Reply #5443
D12-C13-R10-ZD1-ZD2-Q5-R9-C12-D11 still need to connect with the 48v (or 24v) supply though.
Yes, it's requred, and would happily work from the aux supply.

Re: Really universal soldering controller

Reply #5444
Yes, it's requred, and would happily work from the aux supply.
It is the Valley-fill circuit, and I think it has to go back to the main supply. Not sure how would Valley-fill circuit work from the aux supply.