PWM to Analog converter circuit
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Board size is 80mm x 15mm and 20mm high at its most.
A 25mm heatshrink will be fine to cover everything do I will grab some of that.
I had planned to have a single 3/4 pin connector coming off a flying lead and then the end user would add a splitter as required. Panyan asked for a board with fan headers like the one I had in the older vidoes and I thought it cool if it were integrated.
A 25mm heatshrink will be fine to cover everything do I will grab some of that.
I had planned to have a single 3/4 pin connector coming off a flying lead and then the end user would add a splitter as required. Panyan asked for a board with fan headers like the one I had in the older vidoes and I thought it cool if it were integrated.
Soldato
This is great stuff!
It is rather large but is apparently 25.4mm when round, it of course comes flat.
Not as orange as I'd hoped but it's ok.
I've finished Panyan's converter. I was just waiting on the shrink really.
And I also put together the LED PWM dimmer. It has a PWM connector and Molex for power, along with a 3 pin fan header on the board for LED strip hookup. This is even better on the stripboard than it was on the breadboard. The Mosfet remains cool.
Not as orange as I'd hoped but it's ok.
I've finished Panyan's converter. I was just waiting on the shrink really.
And I also put together the LED PWM dimmer. It has a PWM connector and Molex for power, along with a 3 pin fan header on the board for LED strip hookup. This is even better on the stripboard than it was on the breadboard. The Mosfet remains cool.
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Here's one I made for Resident. A few subtle differences. This one has a longer PWM/RPM lead to the connector. It's about 220mm long. The resistor bank is keyed to Resident's needs, needing to drive 2 x Corsair SP120 high performance which I put on the Medium setting, it also has 3 fan headers on board instead of 4.
Obviously not all hot glued and heatshrunk up yet as I wanted some naked shots. I forgot to take some of Panyan's board.
Obviously not all hot glued and heatshrunk up yet as I wanted some naked shots. I forgot to take some of Panyan's board.
Soldato
I'm getting all excited. I haven't ordered the SP120s yet lol.
Thanks again.
I was planning on does a similar thing as with Panyan's one. Just have it sticking out the top and the end sealed with hot glue. The switch is a set once and forget until you change fans thing anyway so it's not something that'll be fiddled with. I will do a cut out for the fan hookups though. That worked out better than I expected as the shrink goes nice and thick when shrunk down.
Did anyone notice the silly error in this image?
Yes it's the wrong gender connector.
This is what it's supposed to look like. Also bent the Mosfet over as Panyan's idea for mounting on a standoff.
Spent a little while compiling a list of resistor to current values.
I wanted to remove the guesswork in calculating the amount of resistance needed for a given fan output. It's a non linear graph as expected. The figures give a 11.8-11.9v maxiumum speed that allows a drop down to 4.2-5.0v at low duty cycle so should be spot on for most uses.
I can throw a circuit together in next to no time now. It's just the wiring that takes the time. Now that I know which resistors to choose that'll help me a lot.
Leeroy asked me to build two circuits, one for his Gelid Icy Vision Rev 2 and one for his two Gentle Typhoon AP15s.
Yes it's the wrong gender connector.
This is what it's supposed to look like. Also bent the Mosfet over as Panyan's idea for mounting on a standoff.
Spent a little while compiling a list of resistor to current values.
I wanted to remove the guesswork in calculating the amount of resistance needed for a given fan output. It's a non linear graph as expected. The figures give a 11.8-11.9v maxiumum speed that allows a drop down to 4.2-5.0v at low duty cycle so should be spot on for most uses.
I can throw a circuit together in next to no time now. It's just the wiring that takes the time. Now that I know which resistors to choose that'll help me a lot.
Leeroy asked me to build two circuits, one for his Gelid Icy Vision Rev 2 and one for his two Gentle Typhoon AP15s.
Did anyone notice the silly error in this image?
*waves hand* i did! i did!
Also bent the Mosfet over as Panyan's idea for mounting on a standoff.
thank you
ive spent the evening cable stitching and i hope when the circuits arrive they will be the final piece of my new build - super excited
This is what it's supposed to look like. Also bent the Mosfet over as Panyan's idea for mounting on a standoff.
So is this PWM adapter for use on a PWM splitter? As it has no rpm lead?
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Soldato
I would assume so as the unit isn't power a fan therefore no RPM feed to report back.
I suspect the 3-pin output is just for connector ease.
I'm assuming the adapter does not attach to motherboard because there is no rpm to feed motherboard to determine PWM signal.
It doesn't do any conversion, it's just an amplifier of the PWM signal that allows one to drive up to 20 Amps of load off the signal. It's a bit off-topic and not really good for fans, although to be fair I haven't tried it with any.
The fan header on board is just there for convenience. Everyone has an old fan they can rip the connector off and hook up to an LED strip.
The fan header on board is just there for convenience. Everyone has an old fan they can rip the connector off and hook up to an LED strip.
Ok.
I brought some fans, some PWM converters, a multimeter and an 0.8A LED strip into the the house for connecting up to my PC and running some final tests.
Seeing as I like graphs and data I thought I'd show how Panyan's reacted to PWM duty cycle through it's range with a load of 0.35A.
A nice smooth transition down from slightly below top speed, down to slow speeds. Speed is consistent too. Only varies by an RPM or two once it's set.
On high setting it's quite different as high is engineered to cope with a fan or two extra.
It runs at full whack and begins to slow down very slowly as duyty cycle drops away, then eventually it drops away. I guess this would be useful if you liked a bit of top end speed early on in the duty cycle range.
The converter has been running now for about an hour up and down and it's warm but not too bad. Ideally the heatsink would be exposed to air but it's using the heatshrink to dissipate it's heat instead.
As I remove the PWM connection the fans instantly speed up to maximum as designed.
I'm pretty happy with that.
Onto the LED strip dimmer. This works quite well but does go pretty dim at sub 30% duty cycle. It's hard to say how this will be with single colour LED strip though. It could do with a bit of a boost at the lower end. Not quite sure how to do that at the moment but will look into it. Maybe some sort of voltage divider coming in with the PWM signal to boost it from 1v average at 20% to 2v or something.
Next up Resident's.
I brought some fans, some PWM converters, a multimeter and an 0.8A LED strip into the the house for connecting up to my PC and running some final tests.
Seeing as I like graphs and data I thought I'd show how Panyan's reacted to PWM duty cycle through it's range with a load of 0.35A.
A nice smooth transition down from slightly below top speed, down to slow speeds. Speed is consistent too. Only varies by an RPM or two once it's set.
On high setting it's quite different as high is engineered to cope with a fan or two extra.
It runs at full whack and begins to slow down very slowly as duyty cycle drops away, then eventually it drops away. I guess this would be useful if you liked a bit of top end speed early on in the duty cycle range.
The converter has been running now for about an hour up and down and it's warm but not too bad. Ideally the heatsink would be exposed to air but it's using the heatshrink to dissipate it's heat instead.
As I remove the PWM connection the fans instantly speed up to maximum as designed.
I'm pretty happy with that.
Onto the LED strip dimmer. This works quite well but does go pretty dim at sub 30% duty cycle. It's hard to say how this will be with single colour LED strip though. It could do with a bit of a boost at the lower end. Not quite sure how to do that at the moment but will look into it. Maybe some sort of voltage divider coming in with the PWM signal to boost it from 1v average at 20% to 2v or something.
Next up Resident's.