Soldato
New user asking for design specs of something an established user has taken a lot of time and effort to develop.
LOL!
PWM to Analog converter circuit
- Thread starter Tealc
- Start date
New user asking for design specs of something an established user has taken a lot of time and effort to develop.
LOL!
I've been moving house so haven't had internet to join the discussion. Yes moving again...a year, almost to the day, since I moved last time. Really hard work but hopefully the kids will be happier in this house and I can hopefully get a half decent electronics workshop on the go in the garage once I've had time to unpack some stuff. I hope to get started on my fan controller project then since I've actually got the components I need from China (took 2 months for delivery) for it.
Anyway regarding the sharing of information. Sorry but I'm not sharing my many hours of experimentation results with someone who doesn't even ask nicely. There are no problems with Speedfan. Max voltage is supply and minimum is less than a fan will spin at. Tach feedback works down to similar speeds as any convential fan and only messes up once voltage of the tach signal drops below the motherboards ability to detect and determine the signal as valid.
Anyway regarding the sharing of information. Sorry but I'm not sharing my many hours of experimentation results with someone who doesn't even ask nicely. There are no problems with Speedfan. Max voltage is supply and minimum is less than a fan will spin at. Tach feedback works down to similar speeds as any convential fan and only messes up once voltage of the tach signal drops below the motherboards ability to detect and determine the signal as valid.
Associate
- Joined
- 25 Oct 2013
- Posts
- 6
I did one better with the possibility of having the higher voltage of 11,80 v how does this 2 versions of a 5A and a lot more!
THIS is VERY SIMPLE CIRCUIT AND THEN JUST LOOK AT THE PICTURES OF ELETRONICS WOKBENCH Multisim HAVE THE LAYOUT! HELLO AND THANK YOU
Soldato
If that's true then why ask for an 'inferior' design? :-/
Soldato
Google translate not working for you in China ? Let me help....
I think the answer you're looking for is " 他妈的关闭 ! "
Associate
- Joined
- 25 Oct 2013
- Posts
- 6
Google translate not working for you in China ? Let me help....
I think the answer you're looking for is " 他妈的关闭 ! "
not work ma mammarua mi da seu coddara in culu o calloni!
Soldato
Hi Tealc, Its been a while.
Just dropping in to see how things are going and leave you some feedback.
Ive been using your converters now for some time about 6 months I think and i must say they are a real asset to my system they took a little tinkering to get right but now they are in I have no issues at all!!!
No third party software just using the bios settings as the manufacturers intended
Happy days.
Just dropping in to see how things are going and leave you some feedback.
Ive been using your converters now for some time about 6 months I think and i must say they are a real asset to my system they took a little tinkering to get right but now they are in I have no issues at all!!!
No third party software just using the bios settings as the manufacturers intended
Happy days.
Well! I've been hunting round for the past week for something that will control multiple fans from the cpu pwm header, Powered from psu rather than board.
Have a new EK kit/loop installed and was wanting the fans and pump to be controlled via the cpu fan cuve.
The last place I thought goolge would bring me is back to OCUK were I first came to for advice for said loop
Awesome work by the way.
One of the few threads I've read in its entirety on any forum!
Only question I have is the max power handling?
Could you do a unit that is capable of running 4 fans + dcp4 pump rated @ 1.8A
Not sure how to set trust as to speak numbers if need to
Have a new EK kit/loop installed and was wanting the fans and pump to be controlled via the cpu fan cuve.
The last place I thought goolge would bring me is back to OCUK were I first came to for advice for said loop
Awesome work by the way.
One of the few threads I've read in its entirety on any forum!Only question I have is the max power handling?
Could you do a unit that is capable of running 4 fans + dcp4 pump rated @ 1.8A
Not sure how to set trust as to speak numbers if need to
Hi Mate.
The circuit itself isn't ideally suited to driving that amount of load but it should be possible to create a variation of the circuit that changes a component or two and shifts the level of the incoming PWM to 12v but would likely lose tach feedback.
I was experimenting on making a several Ampere fan controller that used a similar circuit with the addition of a couple of components that might work but haven't tested or done anything with it in the real world, mainly because of my home move but also because I'd need to buy parts.
It's not actually that difficult to make a board with two channels, one for fans and one for the pump, once I would have made and proven the design anyway. The incoming PWM signal can be split several times to feed several different devices, especially with my original circuit as it draws so little current from the PWM signal.
You've set up trust so you just need to log in to it, using same name and password as forum. You can then send a message. The forum emails me and then when I reply to you we can chat via our own email.
The circuit itself isn't ideally suited to driving that amount of load but it should be possible to create a variation of the circuit that changes a component or two and shifts the level of the incoming PWM to 12v but would likely lose tach feedback.
I was experimenting on making a several Ampere fan controller that used a similar circuit with the addition of a couple of components that might work but haven't tested or done anything with it in the real world, mainly because of my home move but also because I'd need to buy parts.
It's not actually that difficult to make a board with two channels, one for fans and one for the pump, once I would have made and proven the design anyway. The incoming PWM signal can be split several times to feed several different devices, especially with my original circuit as it draws so little current from the PWM signal.
You've set up trust so you just need to log in to it, using same name and password as forum. You can then send a message. The forum emails me and then when I reply to you we can chat via our own email.
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Soldato
Hi Tealc, Its been a while.
Just dropping in to see how things are going and leave you some feedback.
Ive been using your converters now for some time about 6 months I think and i must say they are a real asset to my system they took a little tinkering to get right but now they are in I have no issues at all!!!
No third party software just using the bios settings as the manufacturers intended
Happy days.
Just to add to this, I'm not sure on the exact "anniversary" date, pretty sure it's already passed tbh. I've had my converter from Tealc a year now, driving 2 SP120 Performance fans. It's never skipped a beat. For most of this year my PC has been on from 8am till as late as 2/3am without a break.
It's been a while since I made some converters but in the last few days I was asked if I could make 4 PWM converters for single fan outputs.
Here are the boards.
Now using SMD resistors on the underside to cut down on height. Soldering not wonderful but solid and reliable enough. I really need to improve the lighting in the garage over my workbench.
This is how the fans will attach, off board, unlike normal boards where the fans attach on board. I don't have many of these 3/4 pin headers so only use them on single fan designs.
Edit: Oopps wrong image. Corrected.
Here are the boards.
Now using SMD resistors on the underside to cut down on height. Soldering not wonderful but solid and reliable enough. I really need to improve the lighting in the garage over my workbench.
This is how the fans will attach, off board, unlike normal boards where the fans attach on board. I don't have many of these 3/4 pin headers so only use them on single fan designs.
Edit: Oopps wrong image. Corrected.
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Right.
Spent a little time yesterday knocking up a test circuit that can handle high loads of approaching 2 Amperes and still give tach feedback.
This is what I came up with. Well actually the first iteration had a 10uH instead of the big inductor choke but that got super hot when loading the circuit down.
I must admit inductors are not something I've ever used or learnt about. I don't have many of them to hand as most on old PCBs are not marked so I tend not to harvest them and even if I did suck them off they can be tricky to measure.
Load, roughly 1.6A.
And the trace on the scope. The lower trace is the PWM and the wavy line is the voltage at the load. It looks very different to the trace on my original circuit, this is all down to the inductor resisting change in the voltage.
I'm not overly impressed at the moment. It sort of works and maintains a fairly decent trace. I can get a range of maybe 4v-9v but it is struggling to do more. The 10uH did better but it still topped out at around 10v. It works better in simulation.
Back to the drawing board I think for the moment.
I'm also thinking about using a different high power PNP (rather than medium power PNP) on the original circuit in darlington configuration, perhaps with another of the same type to boost my current but still get manageable heat. I could always go with a bigger heatsink I suppose.
Update:
Simulation is encouraging with the darlington configuration I mentioned. Darlington configuration, as you all know, is where you have 2 transistors in place of just one. The output of one feeds into the input of the other and you can get very high current gain using the solution.
So I've swapped the B772 for a 2N3906 and TIP42 in Darlington and drive seems to allow 2A with only the loss of 1v in simulation.
I expect the TIP42 to get quite warm. It is a much higher rated device though. Max collector current goes from 3A to 6A and watts dissipated max goes from 12.5W to 65W. The downside of using a high power device is very limited current gain, dropping from maybe 80x down to just 20x or 25x so that's why I need the 2N3906 in there. Without it I'd be lucky to see 0.5A. With it have more than enough.
I would need to modify the stripboard design to incorporate the extra device (it's only a small one) plus have room for a larger heatsink.
Spent a little time yesterday knocking up a test circuit that can handle high loads of approaching 2 Amperes and still give tach feedback.
This is what I came up with. Well actually the first iteration had a 10uH instead of the big inductor choke but that got super hot when loading the circuit down.
I must admit inductors are not something I've ever used or learnt about. I don't have many of them to hand as most on old PCBs are not marked so I tend not to harvest them and even if I did suck them off they can be tricky to measure.
Load, roughly 1.6A.
And the trace on the scope. The lower trace is the PWM and the wavy line is the voltage at the load. It looks very different to the trace on my original circuit, this is all down to the inductor resisting change in the voltage.
I'm not overly impressed at the moment. It sort of works and maintains a fairly decent trace. I can get a range of maybe 4v-9v but it is struggling to do more. The 10uH did better but it still topped out at around 10v. It works better in simulation.
Back to the drawing board I think for the moment.
I'm also thinking about using a different high power PNP (rather than medium power PNP) on the original circuit in darlington configuration, perhaps with another of the same type to boost my current but still get manageable heat. I could always go with a bigger heatsink I suppose.
Update:
Simulation is encouraging with the darlington configuration I mentioned. Darlington configuration, as you all know, is where you have 2 transistors in place of just one. The output of one feeds into the input of the other and you can get very high current gain using the solution.
So I've swapped the B772 for a 2N3906 and TIP42 in Darlington and drive seems to allow 2A with only the loss of 1v in simulation.
I expect the TIP42 to get quite warm. It is a much higher rated device though. Max collector current goes from 3A to 6A and watts dissipated max goes from 12.5W to 65W. The downside of using a high power device is very limited current gain, dropping from maybe 80x down to just 20x or 25x so that's why I need the 2N3906 in there. Without it I'd be lucky to see 0.5A. With it have more than enough.
I would need to modify the stripboard design to incorporate the extra device (it's only a small one) plus have room for a larger heatsink.
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An update for Zombiron. I haven't quite finished your converters yet mate. I need to get some hot glue onto the fan connector end so the board doesn't short out with anything. Apart from that they are good to go and have been tested on my oscilloscope as working.
I'm aiming to get them to the Post Office on Friday afternoon for you.
I'm aiming to get them to the Post Office on Friday afternoon for you.
The simplest method would be similar to a circuit I built for Panyan a while back to control the intensity of a strip of LEDs.
This should allow PWM to pass straight to the pump itself and allow it to be regulated by the duty cycle of the CPU. It is not adjustable of course and gives no tach output but if 20% or 30% pump speed is possible without labouring the motor it should be ok. This circuit can drive very high loads.
I don't think there's much need to use an opto-isolator in a circuit such as this as the mosfet works very well at isolating the two voltages from each other and as we use a common ground in PCs there is no point in isolating that off.
I did try the darlington configuration briefly last night but didn't have much success. I may have wired it incorrectly (probably did, or just blew one of the transistors) in my haste to build it on breadboard. As predicted the TIP42 got very hot but I wasn't actually able to adjust the power like in the original circuit.
This high load version will be of some use so I will continue developing and see where it goes. I may even be able to sell one or two to the watercooling aficionados.
