PC motherboard:  PWM 4 pins  to 3 Pins digital converter.  - Page 1
Forum section: electronics / projects

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 28, 2010, 06:11:00 pm
content: It must be on my luck ... the latest motherboard that I got looks unable to control the speed of any Non PWM fan .And so I must ask your help .From my current searches on the net , found this interesting linkan prologue at the 4 pin fans technology.http://www.pavouk.org/hw/fan/en_fan4wire.htmlAnd found also someone who made an circuitry , that he said that it works.Another user looks to had confirm that, and another few was debating about it.Because it uses the negative line to control the output voltage .( picture at the bottom )Two companies they had build this in to (PCB) solution, and its marketed but for a price,I like to make my own.. with your help ..First (not wide) marketed solution.http://www.paqt.co.uk/docs/PaQ_PWM.pdfSecond .. wide marketed solution .. ( Nanoxia PWMX 3-Pin to 4-Pin PWM Converter )http://www.svc.com/pwmx.htmlSchematic found ...

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 28, 2010, 06:48:27 pm
content: just buy the fan Kiri. its not that expensive compared to if you blown out your MB. even cheaper, just buy the non PWM version, just connect to 12V-gnd, no hassle, just $3 or so. i dont understand your circuit, sorry.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 28, 2010, 09:18:59 pm
content: Quote from: shafri on October 28, 2010, 06:48:27 pmThis circuit gets PWM pulses , and converts them to DC , and so the output drives the common fan,and the fan speed changes.About the fan, I got the best ever 140mm for my cooler , but the damn motherboard, does not look to have speed control for both, 4 pin fans & 3 pins fans .Here is the white paper , about PWMhttp://www.formfactors.org/developer/specs/4_Wire_PWM_Spec.pdf

author: fsleeman
author_rank: Regular Contributor
timestamp: October 28, 2010, 09:47:16 pm
content: You might want to check out this thread:https://www.eevblog.com/forum/index.php?topic=1366.0I was trying to use a 555 timer to generate a PWM signal for a 4-wire CPU fan. I was able to generate the required signal but then realized I had a 3-wire fan instead! Although nobody proposed a solution for converting the 555's PWM signal to true DC voltage, the fan works even if accepting a PWM signal. The PWM frequency might need to be a lot lower than the 25-30k those fans usually uses depending on the physical properties of the fan and its electronics. Let me know if you find a simple PWM to DC solution, 555 or not.

author: Time
author_rank: Frequent Contributor
timestamp: October 28, 2010, 09:51:35 pm
content: This seems like a strange way to do it but I don't see why it wouldnt work. Changing the duty cycle would change the speed.I might get corrected when I say this but I think this is a type of rudimentary chopper circuit.Why not just breadboard it and find out if it works?

author: scrat
author_rank: Frequent Contributor
timestamp: October 28, 2010, 10:49:59 pm
content: I don't know if I'm right at understanding what you need.So please correct me if I'm wrong.For a 4-wire fan, you have a 12V source which gets modulated (inside the fan) by the PWM signal (TTL).Now, since old 3-wire fans were linearly regulated, you just have to convert your PWM signal into a proportional 0-12V source.If until here all I said is right, the problem has at least two simple solutions, but since they seem to trivial to me, and you are all but stupid, I assume I have to be wrong somewhere.However,1) You can filter the PWM signal and go to the base of an npn BJT (emitter to ground), and linearly regulate the 12V supply (fan between +12V and collector). Speed sense feedback will provide control by the motherboard, even if transistor characteristic isn't linear. I'd put a2) You can either put PWM signal directly to the gate of an NMOS (source to ground) and drive the fan in PWM, which shouldn't be a problem.In both cases (but especially for the second), a back connected diode (cathode towards +12V supply) in parallel to the fan would be needed.Open collector PWM output from the motherboard means you have to provide a pull-up from the 12V line (a resistor + 3.3V zener?).I'd prefer the second solution, I think that motor phases inductance will do necessary filtering, although some LC could be needed.

author: scrat
author_rank: Frequent Contributor
timestamp: October 28, 2010, 11:12:16 pm
content: I was making the same "mistake" as the circuit it was posted above (image): the sense signal is not referred to ground, which will cause wrong speed detection.With two transistors (a small one and another a bit larger), it should work better.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 29, 2010, 12:40:35 am
content: Dear scrat .. I am not an electronics engineer , so to use your generic info about making something.I have post enough links at the first post, so to even see what I am looking for .And not just that , the working circuitry of it, its pictured on this PDF ( Link also at my first message )http://www.paqt.co.uk/docs/PaQ_PWM.pdfAll that I am asking are an clear simple schematic , with common to find parts , that will work.In about 50 threads worldwide , all those people they stack in theory, and no one produces an simple working idea , like the schematic posted above ,orlike the one pictured on the PDF .That is four transistors , and few resistors.If some one has the knowledge and the free time , to make something usable , he will become an public hero in the EEV and world wide .If there is no new ideas on the table , I will had to try out the first schematic , and see if it works.

author: Time
author_rank: Frequent Contributor
timestamp: October 29, 2010, 12:53:00 am
content: in other words do it for him and don't worry about explaining it

author: cyberfish
author_rank: Regular Contributor
timestamp: October 29, 2010, 04:22:10 am
content: First of all aren't your electrolytic capacitors backwards?And you have a short from PWM input to ground through the base and emitter of the transistor.

author: scrat
author_rank: Frequent Contributor
timestamp: October 29, 2010, 10:48:04 am
content: Yesterday it was a long day, woke up at 5 and posted after midnight... and sorry for being long-winded as usual.My idea was quite simple, I doubted it was too simple, indeed, and so I thought I was missing something.With a few adjustments the posted schematic should work, if you have the patience to wait for me to look at it later. Unfortunately I don't have a fan by hand and the time to give it a try, but if "theory" is worth, it has to work. It could be even simpler, as I'm reading now about the tacho signal on the white paper, which I missed last night.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 29, 2010, 07:27:11 pm
content: Quote from: Time on October 29, 2010, 12:53:00 amThe correct description are ... do it for him , before Dave does it , and blog about it..Millions of young ones, that are exploring the computers hardware , have an major need for an practical solution, about this matter .And I am included .. as young one ...And, at the end , I will have just an spinning fan , and you ..the fame.

author: oPossum
author_rank: Super Contributor
timestamp: October 29, 2010, 09:17:19 pm
content: L1 and C1 may not be necessary for some fans.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 30, 2010, 12:30:31 am
content: Is that tested , or just an fresh idea ?

author: oPossum
author_rank: Super Contributor
timestamp: October 30, 2010, 12:58:47 am
content: Not tested. Just an idea. May require some tweaking.

author: PeterG
author_rank: Frequent Contributor
timestamp: October 30, 2010, 01:11:10 am
content: I have not bothered with the WPM controller my MB has. I simply use the fan from the heatsink connected to the 12v power with a diode in series. The diode drops the voltage just enough to silence the fan without loosing too much performance.Its quick, easy, reliable and not over complicated.Just my 2 cents.Regards

author: Zero999
author_rank: Super Contributor
timestamp: October 30, 2010, 08:54:57 am
content: Quote from: oPossum on October 30, 2010, 12:58:47 amIt's a buck converter, nothing new. The frequency, duty and inductance (not optional) need to be optimised for the load. There's no feedback so the output voltage will change as the load current changes.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 30, 2010, 09:59:16 am
content: Quote from: oPossum on October 30, 2010, 12:58:47 amthis is the problem i think. even the 1st person has tested it and working, the second guy might not makes it work and start to blame and complaint, who knows, he may used different type part and fan? as opossum stated, tweaking is required, and to increase the success rate of the tweak.... experience is required

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 30, 2010, 12:04:18 pm
content: Quote from: shafri on October 30, 2010, 09:59:16 amYes I agree, but from the part of the designer ...He must be the experienced .So to design an PWM demodulator ( 25KHz ) to DC 5 - 12 V .And the funny part are , that this it has be made all ready , from some people in UK , and in China too.And So, they are the experienced and capable , and all the rest on this planet are good,only to just criticize or offer cheap rands.And so , Shafri, save all those comments , or get to work with it ..Every modern motherboard , has an PWM controller build in .Every INTEL fan with four cables , has build in an demodulator .I could probably destroy the housing of an INTEL fan, so to get the PWM PCB , and connect just the wires that drives the motor it self , with to the cables of the New 3 Pin fan ... ( but I hate the idea of destroying an good fan , just for that. )And about the single - simple demodulator s , there is an portion of risk , as their output becomes like an switching power supply , that if it works out of control , it can possibly fry one expensive 25$ 140mm fan .

author: jahonen
author_rank: Super Contributor
timestamp: October 30, 2010, 03:19:02 pm
content: If that buck converter design shorts out the switch transistor Q2, then voltage at the output is same than the supply voltage. Or if it becomes open, then output voltage seen by the fan is 0 volts. Either failure mode should be safe from fan perspective (of course assuming that fan can handle supply voltage).Regards,Janne

author: oPossum
author_rank: Super Contributor
timestamp: October 30, 2010, 04:16:47 pm
content: Quote from: Kiriakos-GR on October 29, 2010, 12:40:35 amThat is what I posted. It will work. The uncertainty is how well it will work.QuoteThat circuit is very poor design. Switching the ground lead of the fan will prevent the tach from working properly. There is no smoothing, just chopping. Using a 78L05 to bias the transistor is quite absurd - a resistor divider from the 12 v supply would be adequate.It is unclear if the second design is supposed to be linear or chopper. There are no values on the cap and resistors. The high gain of the NPN prevents it from working well as linear, and the cap on the base prevents it from working well as a chopper. Will the fan tach work with a chopped supply?If a circuit works for someone, that does not mean it will work for you or that it is a good design. Asking for something that has been built and tested is rather pointless. Reasonable design is far more important than an ugly hack that works for someone.

author: Mechatrommer
author_rank: Super Contributor
timestamp: October 30, 2010, 05:21:15 pm
content: I'm looking forward to see an electrician with "thick hard" skin to get mess around with delicate electronics

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 30, 2010, 07:20:45 pm
content: Quote from: jahonen on October 30, 2010, 03:19:02 pmThanks for the info .. I feel a bit better by knowing this.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: October 30, 2010, 07:40:45 pm
content: Is there any prediction , about the consumed energy of this buck converter ?The on-board fan header , looks in specs with:12V 0.20A ( 1700rpm) 90mm INTEL fan.Or12V 0.20A (1000rpm) 140mm.

author: scrat
author_rank: Frequent Contributor
timestamp: October 31, 2010, 01:28:34 am
content: Quote from: oPossum on October 30, 2010, 04:16:47 pmI must admit my fast "design" has those big issues. And I was not considering the need for a tacho and phase-switching logic power supply, which can't be chopped. I was thinking at the motor windings only, which inductance is usually considered to be sufficiently high to filter out switching. The too high gain of NPN BJT can be avoided by putting a proper emitter resistance.Your buck circuit is too much, in my opinion, I'd rather make it linear, avoiding the use of inductances. Let me make some calculation and a simulation to validate my circuit with the necessary modifications. Could this be accepted as a proof?

author: scrat
author_rank: Frequent Contributor
timestamp: November 02, 2010, 03:31:54 pm
content: Kiriakos defied me (and the matter was very simple), so I couldn't remain indifferentYesterday I had some spare time to try a very simple circuit made with what I had by hand.Since I was trying to make something that didn't require tuning, instead of struggling with transistors I used an opamp (one of the cheapest and widely spread, LM358).The circuit is a very simple power amplifier, the opamp drives the npn BJT to translate the 0-3.3V reference into a 0-12 V output with a max 300mA capability.I simulated the PWM input with a potentiometer, while the output was given to a real fan (12V, 0.11 A). It works (of course!), but the output can't swing up to 12V, as expected, it only goes little above 10V. A diode should solve the swing limitation.I'll make some other tests these days.

author: oPossum
author_rank: Super Contributor
timestamp: November 02, 2010, 04:08:46 pm
content: Quote from: scrat on November 02, 2010, 03:31:54 pmWith a 12 volt supply and and 6 volt output with 300 mA draw, the transistor will have to dissipate almost 2 watts - more than 3 times it's absolute max rating.That is an obvious problem with your "working" circuit. There are more problems.QuoteHow??? Why not PNP transistor like TIP42?

author: oPossum
author_rank: Super Contributor
timestamp: November 02, 2010, 04:13:28 pm
content: Quote from: Kiriakos-GR on October 30, 2010, 07:40:45 pmThe circuit itself uses very little current - less thn 10 mA.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 02, 2010, 04:58:37 pm
content: Well , just from fear , to not damage the expensive motherboard and fan, I did the move and payed the price, for thisNanoxia" PWMX" PWM controller.It will arrive in a week or so.This controller and the company it self , called as German technology ... what ever it called it did cost to me allot , because the shipping cost was a bit high, and I had to buy and some other little things , ( fan grills and dust filters ) so the shipping cost to become worthwhile.Still , I care about the up come of this thread , and I will test the "publicly approved" circuitry,my board has two PWM headers .There is no need to say , that I am dying to see the inner world of this Nanoxia " PWMX" PWM controller.

author: scrat
author_rank: Frequent Contributor
timestamp: November 02, 2010, 05:17:01 pm
content: Quote from: oPossum on November 02, 2010, 04:08:46 pmYou're right in the fact it can't regulate at 300mA on all the range with that particular BJT.The fan doesn't draw its rated current at lower speeds (and so lower voltages) because its torque increases with speed, but it could happen that it gets braked (even stuck) and then the BJT can burn.I was using the components I had by hand, and my fan (as I said above) is rated at 110mA. The transistor wasn't even warm.An PNP will work better on one hand, but I hadn't one to test. It could have the same (but "reversed") problem, since it could be unable to switch off. One (or two) diode(s) should solve (partially, at least) the problem by adding a voltage threshold to opamp's output (see attached). A rail-to-rail opamp would definitely solve it.I know it's a really stupid circuit, and I also know the buck converter will be much better (best efficiency, smaller components). Maybe I'm going to try that too, but I was looking for a simple solution that anyone could make without any tweaking.@Kiri: this last move lets me down... Don't you rely on us?Joking aside: can you tell us how much is this German robbery?EDIT: the resistance above the diode has a "random" value, it must be reasoned a little.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 02, 2010, 05:27:03 pm
content: This German robbery cost about 6 - 7.50 EUR In Germany ..Funny enough , I found the same part in Cyprus retailed at Just 4 EUR !!http://www.eshopcy.com.cy/show.phtml?id=PER.807855But there was no easy shipping to Greece as available option. ( I had contact them )The same shop has base also in Greece, but they do not cooperate.I had to use only an Courier service , that would cost an crazy amount of money (Cyprus to Greece) .And so I got it for 6.88 EUR (plus some other stuff) = 7 EUR shipping ( 30 Total ) From the mother Germany.

author: scrat
author_rank: Frequent Contributor
timestamp: November 02, 2010, 05:41:56 pm
content: @Kiri: Funny... And then we complain about pollution, costs, Far East competition... If transportation is such a crazy thing...@oPossum: I made a bit of reasoning, and discovered that the diode there is not feasibleSo PNP is needed. I think the diode should work for PNP, without the resistor, to avoid rail-to-rail opamp.

author: oPossum
author_rank: Super Contributor
timestamp: November 02, 2010, 06:24:54 pm
content: A simple linear circuit. Not built or tested.

author: oPossum
author_rank: Super Contributor
timestamp: November 02, 2010, 06:33:54 pm
content: Quote from: scrat on November 02, 2010, 05:41:56 pmA simple voltage divider will work well. For example 1k from base to emitter, and 3.3k from base to op-amp.

author: scrat
author_rank: Frequent Contributor
timestamp: November 02, 2010, 06:43:50 pm
content: Quote from: oPossum on November 02, 2010, 06:33:54 pmShould work, too.Can you please explain which is your "thought process" to design transistor circuits with feedbacks, like the one you posted above? I know it's simple, and I can analyse it, but I won't be that good in producing it myself, so I ask.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 03, 2010, 08:38:10 pm
content: Just find an nice document explaining about PWM signals and fans ...http://www.addausa.com/ppt/PWM.pptAnd this its an ready solution.http://www.diodes.com/zetex/_pdfs/literature/pdf/SCMCBR1.pdfI have to admit , that the PWM control system its a bit complex.No one can see how complex it is , if he does not study just a bit , the principals about it..

author: TheDirty
author_rank: Frequent Contributor
timestamp: November 04, 2010, 12:20:19 am
content: I used one of those chips a few years ago, well not the same chip, but an Analog dbCool chip that does the same thing. It had configuration and reporting over USB to control three fans using PWM with two temp probes and a stall warning buzzer. It controls standard 3 pin fans over PWM and has a method to check fan speed pulses only during the PWM 'on' pulse.

author: sonicj
author_rank: Frequent Contributor
timestamp: November 04, 2010, 04:27:42 am
content: Kiriakos,im still not grasping the original intent of this circuit....is it:- the motherboard won't run without a pwm fan attached?- do you want the motherboard to control fan speed or is a fixed speed adequate?- do you want to be able to manually control fan speed?btw, what fan did you purchase? is this to be a case fan or cpu?cheers!-sj

author: scrat
author_rank: Frequent Contributor
timestamp: November 04, 2010, 10:26:29 am
content: Quote from: Kiriakos-GR on November 03, 2010, 08:38:10 pmAs sonicj says, this last link is somewhat confusing: this chip is designed to make a standalone controller for a fan, not an interface for 4-wire to 3-wire standard motherboard fan.PWM principal (especially in this application) is simple, you're just partializing voltage to obtain, as an average, a fraction of it. If you see the fan as a DC motor, to regulate its speed you just increment or decrement the width of the slice of 12V you give it. The average voltage will increment or decrement in the same manner. The speed sense is taken from the tacho signal's frequency.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 04, 2010, 12:59:59 pm
content: Quote from: sonicj on November 04, 2010, 04:27:42 am1) The motherboard are capable to run with 4 or 3 pins fan.2) With three pins fans , the fan will work always at full speed . ( 12V input no speed variation )3) The 4 pin fan , will use the PMW signal ( pin No4 ) , so to adjust the fan speed as needed .The PWM to DC converter , it will effect the voltage input of the three pin fan , and so it will start to have variable speed .All motherboard headers have an 200mA DC output , enough current for specific fans , that does not need more than that.And above I had posted an guide about fan size VS rpm = 200mAThe top wanted in this wish list , its an easy to build PWM to DC converter.This one will be able to handle ( or just about) the 200mA load.The best ever solution it would be the one, that can supply more current up to 600 - 700mA ,enough current to run even the faster 120mm fans ( 2400 - 2800 ) rpm .At the most PWM to DC converters , it looks that the addition of an potentiometer that limits the voltage output to an specific range , its an easy to do .Well this looks useful , because I can use an monster size Panaflo FBA12G12H 12V 0.6A ,to operate at lower rpm speed as max , and still to through large amount of silent CMF .The design posted by @TheDirty, looks great about the usability factor at list.Three outputs, plus current amplifiers ( drivers ) that could handle anything, and possibly fans above the 200mA .Basically , anything that it can handle 800mA to 1A as current output , it would be called ,the ultimatein specs PWM to DC converter.In this scenario , the output transistors ( alike the 2N3055 ) they could draw amps by be powered,by molex connectors.With this design you can run any monster 120mm fan , at full speed with no fear.My next move : To email Nanoxia about the max mA output, that their controller are rated for.I am aware of , that some of my requirements, are possible to be made, and some not .

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 04, 2010, 01:47:36 pm
content: Quote from: Kiriakos-GR on November 04, 2010, 12:59:59 pmmakes me confuse... if its constant 12V, why dont just use 2 pins (+ve -ve)? whats the 3rd (sense) pin is good for?looking back at your OP, you said you want to control non PWM fan? and i ask... a non PWM fan got a sense output? if yes, then will it be compatible with 4pin sense input?Quote from: Kiriakos-GR on November 04, 2010, 12:59:59 pmi suggest you stick with the standard, if the MB provide 4pins only and capable of 200mA only, then better stick to it, its not designed that makes the MB/CPU crashi think it means, the CPU will only need such amperage/wattage to do the cooling. earlier you made a thread on saving electricity, now you want to waste it by pushing to 600mA/higher limit. i admit that i've added some more fans inside my CPU (12V constant), but not to cool the CPU further, but to control dust entry and departure point so it will not enter randomly and stuck on top of the MB or other electronic stuffs. i trust the fan that comes with my CPU will do the job better enough.now you want to make a tweak to the stuff you are not familiar with and expect somebody comes out with bulletproof and proven solution. i think you fight is not worth enough. thats why i still reluctant to struggle to google on better solution for you and keep rambling nonsense'ly, even if i have the capacity and knowledge. not only the electricians have blown things up you know! electronicians too, but more dangerously, in a silent manner, sometime even more difficult to trace the blast point. you adviced me/us something... that i will give it back to you... you said "dont give the advice to kids, they can do some dangerous stunt" sounds something like that. and i know you are not kid, so i'm advicing... with respect, its for your own good. its your MB you are playing with! unless you are willing/ready to scrap that? Cheersps: any info here are good though, given the right purpose for it and you really know what you are doing, especially increasing (overclocking) the wattage of the circuitry involved.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 04, 2010, 06:15:23 pm
content: Quote from: shafri on November 04, 2010, 01:47:36 pmshafri dot not kill your self ... with generic thinking ..The motherboards PWM circuitry its an design, designed by INTEL , the " how-to " its described on the first post links.http://www.pavouk.org/hw/fan/en_fan4wire.htmlThe three pin one , same story .... + /-/ Sense/At the old three pin header (CPU header) , this was able to control the DC ..Today the default (CPU header) its the PWM , that partially supports the three pin fans.Quote from: shafri on November 04, 2010, 01:47:36 pmAll that I suggested - wished , was the PWM to DC converter to was able to amplify "some how" the output from 200mA to 700mA ... is this a Sin ?Plus , one such capable circuitry, has lesser chances to burned out.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 04, 2010, 06:33:31 pm
content: What I plan to try , its to drive with the Nanoxia PWMX an BD135 , if this is able to cooperate, I just got up to my target.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 04, 2010, 06:47:52 pm
content: Quote from: Kiriakos-GR on November 04, 2010, 06:33:31 pmif you'd be more specific, then it will be easier for the rest of the "geeks" i think

author: scrat
author_rank: Frequent Contributor
timestamp: November 04, 2010, 07:07:54 pm
content: Quote from: shafri on November 04, 2010, 06:47:52 pmMaybe it's not so easy to the greeks to be easy for the geeks.Sorry for the nonsense, perhaps I'm suffering for low glucose level in my blood...

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 04, 2010, 11:27:38 pm
content: No problem mate ,I have too much sugar in my blood , and so I drink coffee with out sugar,and this causes to me , an over excitement

author: scrat
author_rank: Frequent Contributor
timestamp: November 05, 2010, 12:27:24 am
content: Ok, after a good dinner one recognizes the madness of previously done things... I was just wandering your reaction (my sentence involved the Greek, but just because of a rhyme reason). I enjoy seeing you're a tongue-in-cheeck (a composite word I never have read, but Wordreference suggests it) one too. And you must be sweet (not that this moves my interest, let's state it!), if you have so much sugar in your blood.Enjoy a good coffee, but beware of over excitement!

author: sonicj
author_rank: Frequent Contributor
timestamp: November 05, 2010, 02:29:02 am
content: Quote from: Kiriakos-GR on November 04, 2010, 12:59:59 pmok, i understand now!that panaflo looks like it has quite the following! i have older media center box with nothing but FBA08A12L's. oldskooli recently built a box with a Noctua 120mm case fan. silent computing has come a long way since i last messed with those panaflos! the noctua is truly amasing! the little bit of noise it does make is like nothing you've ever heard before.i don't have the time to try this, but what about a lm317 with appropriate RC to convert the pwm to dc reference?-sj

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 08:05:23 am
content: Quote from: sonicj on November 05, 2010, 02:29:02 amThere is no try, either do or dontto be able to enter "Kiriakos Design Contest", you must provide a sound and "proven to be working" schematics. he dont want anything that involve any explosion.

author: PeterG
author_rank: Frequent Contributor
timestamp: November 05, 2010, 08:59:24 am
content: The speed of a 3 pin fan header can be adjusted. The mobo bios must be set to manual fan speed and an app like Speedfan used to control the speed of the fans. The third pin is used for tach only. The speed on the 3 pin fans is controlled with voltage rather than pwm.Regards

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 10:16:59 am
content: Quote from: Darkman1969 on November 05, 2010, 08:59:24 amsimple but nice explanation! i was just confused when Kiri said, its 12V constant only and cannot be controlled. now its become clearer that a "voltage averager" can do the job. and oppps! i dont have any schematics... sorry

author: scrat
author_rank: Frequent Contributor
timestamp: November 05, 2010, 11:20:33 am
content: Quote from: shafri on November 05, 2010, 10:16:59 amHe was only saying an obvious thing: if you directly connect a 3-wire fan to a 4-wire output the fan will be at 12V supply all the time, since the PWM control isn't connected. They've certainly made the 4-wire connection like that for compatibility reasons.

author: PeterG
author_rank: Frequent Contributor
timestamp: November 05, 2010, 11:42:02 am
content: CPU fans generally use a 4 pin header, case fans use a 3 pin header. The believe the 4 pin header is used for the cpu because it is easier for the bios to control the fan speed accurately and also detect failure. Case fans do not require such control. Most 3rd party cpu cooling fans come with adapters when required to connect to either the 3 or 4 pin header. Better quality cpu fans come with a 4pin connector, some with there own fan speed controller.Regards

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 11:46:33 am
content: @scrat: maybe its just my ignorance

author: scrat
author_rank: Frequent Contributor
timestamp: November 05, 2010, 11:53:10 am
content: Quote from: shafri on November 05, 2010, 11:46:33 amOr you're just too angry with Kiriakos" " " " " inattentive, like me.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 11:59:52 am
content: Quote from: scrat on November 05, 2010, 11:53:10 amno dont get me wrong, i like him! he is one of the cool guy with alot to talk... or complaintps: and he can transfer a thread from low energy level, to "high" energy one, didnt you noticed?ps: if i angry at him, i will simply ignore him and let him blow his MB the sh*t out!

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 05, 2010, 12:26:53 pm
content: Quote from: Darkman1969 on November 05, 2010, 11:42:02 amThat's True , and I had emailed Gigabyte , asking about the actual RPM scaling against temperature raise.As it looks that the PWM controller , it will offer an base voltage (min rpm to 700-800 INTEL fan) ,and the controller it will increase the speed of the fan if the temperature raise above an specific limit.The reply that I got from Gigabyte was , that if the CPU temp gets more than 40C , the fan will work at full rpm ( 1700) , and if it temp drops down, the fan rpm will fall back to the base minimum (700-800 ) .I bet that this was an quick answer ... If I believe this .. it translates to, that the PWM its an stupid non scalable way about handling speed of motors .I know that shafri hates me , because I am an Olympus digital fun boy, all the Canon fun boys are the same..

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 12:45:21 pm
content: Quote from: Kiriakos-GR on November 05, 2010, 12:26:53 pmno you are utterly wrong about the PWM. makes me thinking, the actual circuitry that you are looking for might resides in the 4pin fan, and most likely the fan is the DC, its just the PWM->DC converter already embedded in side it.and why you still understand me wrongfully?! i'm a practical man, i dont care what brand it is! i only care what comes out of it, for the sake of humanity (technologically and psychologically)!i'm not a "fun boy"!and i dont care if you are!ps: I choose Canon because it serves my purpose! I wish i could convert to Nikon, but there is no turning back anymoreat least not... for now.fyi: I'm building TTL remote flash trigger compatible to most popular camera brand (TTL capabled), and i would loved to include the Olympus, its just i dont have the neccesary gear to R&D.here!if you dont believe me! need to register i think to see the pictures.

author: sonicj
author_rank: Frequent Contributor
timestamp: November 05, 2010, 12:57:01 pm
content: canon is cool for chdk.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 01:10:27 pm
content: ooo! i didnt notice there is "Canon Hacker's Development Kit"! o well, i will not bother! since my machine is more than twice the price of rigol, if it broke, i'm not sure someone will be able to fix that other than Canon Service Centre. as i said... it serves my purpose already

author: scrat
author_rank: Frequent Contributor
timestamp: November 05, 2010, 01:36:52 pm
content: I'm pretty sure things on that famous fan controller work like this:- The mother-board decides (in its maternal wisdom) at what speed her son /the fan /has to run (a little bit of verse).- The speed controller on the motherboard measures fan's speed from the tacho signal: frequency of tacho signal = rotations/sec.Worst issue here is the motherboard speaks English, while tachos are Mexican, and so they only speak Spanish.- As in all feedback regulators, if the frequency of tacho signal is lower than the desired spinning rate, PWM duty-cycle will be increased, while it will be decreased in the opposite case.- The 4-wire fan controller takes the PWM signal and 12V supply. With the 12V supply it feeds the control electronics (minimal, but there is one, with 1 to 3 Hall sensors to detect rotor position). A PWM switcher just executes chopping (slicing) of the 12V supply, just applying the PWM to it, ending to have a 12V square wave with the same shape (duty-cycle at least) as the input PWM coming from the motherboard fan controller. The control electronics on the fan then gives this PWM signal (power) to the motor, connecting in the proper direction 2 of the 3 phases at a time, depending on the rotor position (sensed by Hall sensors, since the rotor has a magnet). The fan is in fact a BLDC synchronous motor.Hall sensors could be avoided (sensorless BLDC), but I doubt they do it into a computer fan, since it will require using a more complex controller (this is usually done with an MCU).As I said I'm not sure at 100% of this, as I never opened one of those, but this is the explanation I give myself, and it seems quite straightforward.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 05, 2010, 06:55:49 pm
content: Interesting explanation that targets about wide understanding for the masses .But the true hierarchical pyramid goes differently.Intelbuilds the CPU and the primary motherboard design,with all the extras that would help the specific CPU design, to be functional and safe .Intelselects the CPU fan specs : rpm / duty cycle / electrical requirements.Intelsends white papers of the original design to all the motherboard manufacturers,so to follow the original design unchanged !! ( For compatibility reasons mostly about the supplied Intel stock cooler and motor )On this documenthttp://www.formfactors.org/developer/specs/4_Wire_PWM_Spec.pdfpage 14 , its all clear about the base theory.Result :the PWM circuitry of any motherboard that supports an specific INTEL CPU family are all alike.a) Motherboards that supports both CPU generations 65nm & 45nm , are capable probably from Bios,to supply an different duty cycle info, so the motherboard to correspond correctly , with the two versions of the INTEL stock coolers. ( different motor specs )So far I was aware, the fan speed detection wire (3 pin), was there to just trigger an Bios alarm ,about damaged CPU fan , and nothing more.( And so dear shafri , its not the motherboards brand that makes any difference about PWM )About the 3 pin CPU headers and motors (INTEL CPU coolers) :a) Its another INTEL design , that was followed some years back by the motherboard manufacturers,and had as main target to support again the INTEL CPU coolers.( this design it was had his own logic (automated control circuitry) able to be bypassed and controlled also by software , the famous speedfan software reviled that it was an scalability " min to max rpm " of five steps.The marriage of PWM 4 Pin with the automated control circuit of 3 pin fans :There is no such thing , the motherboard manufacturers in order to do that, they need to build both speed control circuits , plus an setting about manually activation from Bios.By having the PWM one, active by default .This dual solution gets the cost up , and it starts to not be widely in use any more.Today :Every computer owner , who cares to add an third party cooler ( heat-sink fan compo)needs this PWM--> DC board , so to be able to use and choose an fan , with out to be limited,from the current few PWM, aftermarket choices.There is few high quality 3 pin fans , that they do worth having them.And there is no equivalent in the PWM marketed ones.Additional info about the PWM signal.It can used to trigger more than one fan , but its one fan, it must be connected on different header.My motherboard has two PWM headers , and another two 3 Pin type ( case fans)( bad news from the German that I ordered my controller, he will had to delay shipping,because he had no stock of something in the list ... but promised that I will receive an extra gift)Estimated arrival about 12 of November.

author: sonicj
author_rank: Frequent Contributor
timestamp: November 05, 2010, 10:50:28 pm
content: Quote from: shafri on November 05, 2010, 01:10:27 pmits only for their P&S cameras afaik. the "firmware" is non-invasive. it runs on top of the stock firmware so chances of killing your camera are nil. if you are into creative photography, i highly suggest giving it try. you can pick up a compatible model for less than $100 on ebay. the motion, intervalometer, and RAW scripts allow for some pretty amazing shots with a consumer P&S.sorry for the threadjack! at least its about cameras!carry on!-sj

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 05, 2010, 10:56:37 pm
content: nice workout Kiri! kudos!@sonicj: thanx 4 d info.ps: looking at the vidz reminds me of Karl von Moller's, when will his SoE be out? hmmm.

author: PeterG
author_rank: Frequent Contributor
timestamp: November 05, 2010, 11:12:46 pm
content: I am happy with my EOS 500D for now.Yeah ok , i am a canon fan.Regards

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 06, 2010, 01:09:14 am
content: Quote from: Darkman1969 on November 05, 2010, 11:12:46 pmHow many rpm ?

author: TheDirty
author_rank: Frequent Contributor
timestamp: November 06, 2010, 03:38:43 am
content: Quote from: Kiriakos-GR on November 05, 2010, 06:55:49 pmMotherboard manufacturers only uses the basics of the Intel original reference design now, it's not a straight copy. They definitely do not use the reference design for fan control. Speedfan constantly has to update itself to handle all the different fan control methods used by different manufacturers.Many newer motherboards allow both PWM control for 4 pin fans or VDC control for 3 pin fans using the same 4 pin connector. The Gigabyte can select Auto Mode, PWM mode (4pin), or VDC mode (3pin) from within the BIOS.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 06, 2010, 09:30:27 am
content: Quote from: TheDirty on November 06, 2010, 03:38:43 amahhh! software mod!

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 06, 2010, 06:08:28 pm
content: The VDC control for 3 pin fans , by just software control, from windows, its not something that great.Yes I agree that some motherboard manufacturers, does not use the reference design for fan control,but they do that, so to use alternative chips = cutting corners & cost.Mark , how much it cost ? just the part list of your above design ?

author: TheDirty
author_rank: Frequent Contributor
timestamp: November 07, 2010, 01:47:45 pm
content: Using alternate fan control methods isn't cutting costs or methods at all. Some of the fan control on non-Intel motherboards far surpasses that of Intel reference designs.The design I used uses an Analog ADT7460, looks like they sold this line to ON Semi. In theory you can connect these directly to the SMBus on your motherboard and talk to it with a driver and you wouldn't need any other interface hardware.http://www.onsemi.com/PowerSolutions/parametrics.do?id=2126In my design I have the ADT7460, with a cheap microcontroller talking to it over I2C and I have a FT232RL to allow the PC to talk to it to reprogram the temp/fan speed maps and to get the current fan speed data. Looks like the ADT7462 is $8 and the FT232RL is $4.50... with the uC and MOSFETs, I would say it's about $20. If I was doing it now, I'd use a uC with integrated USB, maybe I'd get rid of the ADT chip all together.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 07, 2010, 02:30:20 pm
content: By just looking the PCB that you had made ,I had the feeling that this was what I am looking for.But, by looking in use SMT parts , I lost my interest about replicating this design.Even so, I feel the need to congrats you, because you got that far.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 07, 2010, 05:17:05 pm
content: Quote from: Kiriakos-GR on November 07, 2010, 02:30:20 pmthere is always DIP replacement?

author: Unknown
author_rank: Unknown
timestamp: November 07, 2010, 05:54:49 pm
content: Quote from: shafri on November 07, 2010, 05:17:05 pmAs long as they're old parts, few new parts are brought out in DIP anymore. If you want to use modern parts, it's hard to ignore SMT.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 07, 2010, 06:11:02 pm
content: Quote from: alm on November 07, 2010, 05:54:49 pmthen you should awardReply #1as a winner Kiri!

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 08, 2010, 01:21:57 pm
content: My brain had stuck to this NANOXIA PWMX ..How its possible, no one to have even open one, and take some pictures !!( I just finished the build of my new quad core computer,I had to format and all , but now its just perfect " super fast and silent " ,but I like the idea of having an ace under my sleeve for the Summer time.)

author: TheDirty
author_rank: Frequent Contributor
timestamp: November 08, 2010, 01:44:11 pm
content: There's a thread on SPCR about this, with a link to this Maxim app note:http://www.maxim-ic.com/app-notes/index.mvp/id/3149Plus pictures of the Manoxia opened up:http://www.silentpcreview.com/forums/viewtopic.php?t=52555Looks like it's really cheaply made. Soldering is terrible.

author: oPossum
author_rank: Super Contributor
timestamp: November 08, 2010, 04:57:07 pm
content: I think it is rather poor design. The microcontroller controls a crude 4 bit DAC, so no more than 16 speeds - maybe less. The transistors may not share current equally (no emitter resistors). Linear operation is inefficient and will drop about 1 volt at max speed.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 09, 2010, 05:30:50 am
content: Alleluia ...speechless .. Thanks .As soon it arrives , I will verify the schematic.About the pictures I had some difficulty to find them on the thread..It is external links, and so here they are...http://www.xs4all.nl/~joeribl/images/pwmx-front.jpghttp://www.xs4all.nl/~joeribl/images/pwmx-back1.jpghttp://www.xs4all.nl/~joeribl/images/pwmx-back2.jpg

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 09, 2010, 05:48:29 am
content: Quote from: TheDirty on November 08, 2010, 01:44:11 pmWho cares ..

author: sonicj
author_rank: Frequent Contributor
timestamp: November 09, 2010, 05:53:40 am
content: wow! thats pretty bad!

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 09, 2010, 06:09:42 am
content: Quote from: sonicj on November 09, 2010, 05:53:40 ammaybe its that hard for him to find a good flux or reflow machine supply (like me). so need to DIY from what he already has (solder only). the PCB is nice though.

author: oPossum
author_rank: Super Contributor
timestamp: November 09, 2010, 06:12:59 am
content: Build quality is typical for a low cost product.PCB is thin and slightly warped. It does not appear to be FR4.Wave soldered (not reflow), flux residue on board.Some flux on top side too. Pot is smooth and tight.Connectors are keyed. Heat shrink, but no strain relief.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 09, 2010, 06:24:32 am
content: Quote from: oPossum on November 09, 2010, 06:12:59 amnot hand soldered huh! well ok... thats UGLY! my hands are better than that.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 10, 2010, 04:44:51 am
content: I do not believe this ... even more pictures .Can any one predict the output in Amperes ? If I use as 12V input from molex ( so to not stress the fan header ) and the rest cables normally connected !!It looks that there is four output transistors named as J3.The PWM reference circuitry , have as info , that the output circuitry it must be capable to offer even 2A ,for 1-2 ms ( starting current ) .edit:Those must be called as JFET , found one description about output as 35mA/V .At 12V X 0.35 = 420mA its one By four times = 1680mA ( yep that's sounds close enough )

author: oPossum
author_rank: Super Contributor
timestamp: November 10, 2010, 06:06:37 am
content: Q1 to Q4 are NPN as shown in the schematic. They may beS9013orMMS9013. There is no standard for marking SOT-23 package components.Q5 and Q6 carry current to the fan. I estimate they will be warm at 100 mA, hot at 200 mA and dead at 400 mA (continuous @ 6V to fan).

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 10, 2010, 09:32:27 pm
content: What about replacing those with better ones ... is there any suggestion.I need 600mA continuous @12v , and 2A peak for 2 milliseconds.(the size does no matter )

author: oPossum
author_rank: Super Contributor
timestamp: November 16, 2010, 05:15:57 am
content: The fan will draw less current at lower voltage, so it may be OK as-is. Try it and see what happens. If it blows up then mod it.A CFP (Sziklai) output using a PNP transistor (Q6) in a TO-220 package should be good for 2A or more with a small heat sink.Modified schematic...

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 16, 2010, 09:01:35 am
content: NiceIn the primary design Q5+Q6 works in parallel .In the last the Q5 drivers the larger Q6.I will have a look about the BD part specs on my vrt books.

author: oPossum
author_rank: Super Contributor
timestamp: November 16, 2010, 09:09:48 am
content: I built a circuit to characterize PWM to voltage converters.SchematicSource code, schematic, and captured dataThe first test showed that the Nanoxia PWMX was not working correctly. The problem was bad solder on the emitter of Q3.Plot showing Voltage (left axis) vs. PWM % (bottom axis).After fix. Pot set to max fan speed (full CW).Pot set to middle of rotation.Pot set to min fan speed (full CCW).Pot set to middle voltage.Comparison. Max (violet), middle rotation (red), middle voltage (green), min (blue).Comparison of output with no fan (blue) and fan that draws 220 mA @ 12 volts (red).Noise in the plots is due to fan commutation. There is no noise with no fan connected.

author: oPossum
author_rank: Super Contributor
timestamp: November 17, 2010, 08:41:30 am
content: Tests at 20, 25 and 30 kHz. It measures both the on and off duration of the pulse. Very good.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 17, 2010, 12:36:25 pm
content: oPossum,if you had get in to the "Win a UEi DM391 Multimeter" thread,I wish with all my hart, to get it( its an long shot, but this is my wish )

author: oPossum
author_rank: Super Contributor
timestamp: November 17, 2010, 04:59:52 pm
content: I built this on a breadboard...Tested with 220 mA fan. Results...Note: Max current with Q2 2N4403 or similar is ~300 mA. Use larger Darlington PNP like TIP125 for more current.Use R5 if fan must run below 20% PWM.

author: scrat
author_rank: Frequent Contributor
timestamp: November 17, 2010, 05:51:32 pm
content: Designed, built, tested, indication of possible modifications. Great job, oPossum!

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 17, 2010, 11:55:00 pm
content: I can see only one part missing from the last design, the pot that I will control the final DC output even at 100% PWM .(Like the PWMX does.)( About the 2N4401 i have the equivalent BC337 next to me X2 )

author: oPossum
author_rank: Super Contributor
timestamp: November 18, 2010, 09:24:42 pm
content: I built this on a breadboard...Tested with 220 mA fan. Results...Fan runs at 25%, but tach does not work until 32%Increase R1 to move start of curve up (so fan will run at lower PWM %). Decrease R6 to move entire curve down (so max speed is reduced).

author: oPossum
author_rank: Super Contributor
timestamp: November 18, 2010, 09:28:25 pm
content: PWM % vs RPM for genuine Intel 4 wire fan supplied with boxed Pentium 4 LGA775

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 18, 2010, 11:57:01 pm
content: The actual dream or wish , of any one who needs this design.Are to use an 120mm fan with this circuitry .The only problem are , that even the best ever 120mm fan it will start to become audible above the 1000-1200rpm .And and so the 20%PWM ( start point it should represent the 600rpm ) and the 100% PWM ,the 1400rpm mark.I bet that with this design , and the adjustment points R1 & R6 , everything looks possible.I think that I am going to build it.The German that I ordered the PWMX , he did not shipped anything after all this days, with the excuse that he run out of stock about the PWMX , and he waits to restock.I had kick his **** today ( after of two weeks of patience ) , and put the Paypal on his tail, so to get my payment back.

author: oPossum
author_rank: Super Contributor
timestamp: November 19, 2010, 09:53:05 am
content: R1 = 820 R6 = 1kR1 = 820 R6 = 820R1 = 820 R6 = 680

author: oPossum
author_rank: Super Contributor
timestamp: November 19, 2010, 10:11:40 am
content: Violet: R1 = 470 R6 = 1kRed: R1 = 820 R6 = 1kGreen: R1 = 820 R6 = 820Blue: R1 = 820 R6 = 680

author: oPossum
author_rank: Super Contributor
timestamp: November 19, 2010, 01:34:58 pm
content: Adjustable version.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 19, 2010, 03:26:19 pm
content: ok, just did the parts list ... For the Adjustable last version.ResistorsR1= 390 ohmR2 / R4 = 2.7kR3 = 1KR5 = 220 ohmR6 = 560 ohmTimers potsR6A / R1A = 500 ohmCapacitorsC1 = 10 uf (mF) ( Capacitor electrolytic 16v )C2 = 1n ( ceramic )TRQ1 = 2N4401Q2 = TIP42I am getting out to get them.. ( home town)Its best that way , so the original design to be replicated,with out the use of equivalent parts.

author: TheDirty
author_rank: Frequent Contributor
timestamp: November 19, 2010, 06:34:57 pm
content: Great work oPossum.Sadly I doubt you need to buy parts. Now that the schematic is on the internet you will be able to buy it all as a product in another couple days for $3.50 at dealextreme.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 19, 2010, 07:22:40 pm
content: I will handle the marketing in Europe ...Many poor souls will find some joy ... but they must get the basics...I had some parts in my boxes, but spent 2EUR to get the trimmers + transistors + some 1/2Watt resistors.I did not find the 2N4401 , I will had to use as alternative one, the BC637..

author: scrat
author_rank: Frequent Contributor
timestamp: November 19, 2010, 11:58:39 pm
content: Quote from: TheDirty on November 19, 2010, 06:34:57 pmThe strange thing is why the Nanoxia board, besides the poor production quality, was quite complicated for the task (it used a digital IC and 4 transistors), while not woking too good. Nonetheless, they have their market...

author: oPossum
author_rank: Super Contributor
timestamp: November 20, 2010, 05:51:13 am
content: Quote from: scrat on November 19, 2010, 11:58:39 pmGerman Design

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 20, 2010, 01:28:26 pm
content: Quote from: oPossum on November 20, 2010, 05:51:13 amYou deserve to get " your blood back "( About Nanoxia )But, the troublesome solder point on your PWMX , it can not be called as plague !!But the fact remains ... those Germans they cooperate with "build for low budget" partners ..That's a poor corporate decision .In few hours, I will assemble the American design ..

author: scrat
author_rank: Frequent Contributor
timestamp: November 21, 2010, 11:14:58 pm
content: BTW, I'm curious about which IC they used. Was it an MCU?It seems a case of "making difficult the easy by means of the unuseful" (as my father used to say).

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 22, 2010, 01:01:32 pm
content: Are you talking about the Nanoxia ?If so the SOIC 14 it is the name ... but it looks that there is about five IC's from other makers.Just the same part ... I do not remember the code , it must be like CD74XXXXX.

author: oPossum
author_rank: Super Contributor
timestamp: November 22, 2010, 02:50:15 pm
content: I assume it is a microcontroller. I looked at it with a 10x lighted magnifier and didn't see any markings.SOIC-14 == Small Outline Integrated Circuit with 14 pins (package type, not part #)

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 22, 2010, 03:03:08 pm
content: Yes , even the pictures does not show ID markings ... I bet that they had soldered it, upside down.As about me , I have do the half circuitry , soon I will do and the rest.Placing the parts on PCB , the parts orientation its a small puzzle.I have 3-4 small PCB's, all at the same dimension , but the length falls sort, so the design to have the best look.I am still cooking it ..

author: oPossum
author_rank: Super Contributor
timestamp: November 29, 2010, 01:47:39 am
content: High current mod for Nanoxia PWMXThe higher gain of the CFP provides higher voltage and the ability to user higher current fans (with a heatsink on the PNP transistor).Before (red) vs. after (blue)

author: oPossum
author_rank: Super Contributor
timestamp: November 29, 2010, 01:55:23 am
content: DIY clone of Nanoxia PWMXSource code for PIC

author: oPossum
author_rank: Super Contributor
timestamp: November 29, 2010, 04:18:12 am
content: Watch the 12HV609 decode PWM.

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 30, 2010, 02:24:13 am
content: Great work oPossum .. ( your suggestions will help many )I managed to clear the mess with the German seller , and my Nanoxia is on the way.I had some urgent tasks this week, and I have left my small project unfinished.But now with your latest addition " The moded Nanoxia " , I think that is best to wait and see what will be my final needs.By the way , why you had use on the moded Nanoxia an TIP32C and not TIP42 ?

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 30, 2010, 09:03:48 pm
content: The Nanoxia arrived , and I start testing it ...I must admit that it works !!( no i did not open it up to check the PCB yet )I must also to admit , that aftertrulytesting it , I am a bit disappointed .I was count that this adjusting pot , it will make the deference that I was looking for ,so to adjust with 100% PWM , the final DC output under my own likes .( Or better said , to be able to adjust the fan speed at an specific low RPM value)I found one software made by Gigabyte ( officially not compatible with my motherboard )called as Easy Tune 6 ... ( It supposed that my motherboard are compatible with the older version Easy Tune5) ...Any way the new works fine for me and has an amazing tool .... I can control the PWM signal of my CPU Fan header from 10% to 100 % ..And so I got lots of playing around with Nanoxia + The Big fan + PWM signals .I am not that high-tech , graphs and Oscilloscope , but I managed to make some pictures that shows how this thing responds ...My main complain about it , are the scalability of the Pot ( potentiometer ) it self !!The adjustment like Low - High are very poor for my taste ...According my tests it represents just 200 rpm change from low to High ..This poor behavior ( un-moded ) makes it, look like a poor choice !!Who cares for just 200 RPM change ?I am happy and sad together ...Pictures of my tests , and pictures of the box ( for the collectors out there), that actually its not carton, but its made by strong nylon.http://en.wikipedia.org/wiki/Nylon

author: Kiriakos-GR
author_rank: Super Contributor
timestamp: November 30, 2010, 10:41:56 pm
content: And more info about the scalability issue ....I call it as issue , because I dislike the results ..Its probably the motherboard that its not made " smart " enough ...Any way I continued playing with the Gigabyte software and the motherboard PWM controller,And I did the amazing , I got step by step from 10 - 100% so to find exactly the actual scalability points.And I did ... ( picture below )Well the point is that no matter how smart or damn made , the Nanoxia is made,the scalability of the motherboard it self , are set by this specific way .With just five fan speeds scaling ( or five PWM levels of pulses as output).So far so good .Well the PWM-X starts to feel hot at the max Fan speed ( Fan specs 12V 600mA ) , I think that now it gets less voltage from the PWMX , and it must use about 500mA .I did not test it at full speed for more than 40 seconds , and so far I did not damage anything.I will take a big breath , and think of what I will do tomorrow, with clear mind .

author: fitnessfan
author_rank: Newbie
timestamp: April 13, 2013, 10:32:13 pm
content: Quote from: oPossum on November 19, 2010, 01:34:58 pmSorry, but I know that the thread is 3 years old. %-B I need a 4-pin pwm to 3-pin voltage converter. I am new to this.Could someone help me to make a circuit on curcuitlab? I don't know the parameters for TIP42C. (Can we use TIP42C here)? Please simulate it with DC Sweep.Click on the image!

author: TonyPh
author_rank: Regular Contributor
timestamp: April 15, 2013, 01:40:35 pm
content: Here's my effort.It's basically copied from a Phanteks converter with a few modifications to make it adjustable. This one was put together for a GPU fan header to convert it's PWM to 2x 3 pin PC fansIt basically, I think (I'm new to electronics), just turns the 3.3v or 5v PWM into 12v and uses the capacitor to smooth out the 12v at the fan end, working a bit like a filter. It's good for around 800mA of connected fans right down to 60mA or less and keeps voltage near 12v quite well, at least until you get to the high current draw anyway. It uses a BS170 Mosfet and a B772 PNP medium power transistor, along with a few passives. It's the simplest implementation I've seen and costs me less than £1 in parts.I don't have a schematic at the moment.

author: eikei
author_rank: Newbie
timestamp: May 21, 2013, 12:49:26 pm
content: fitnessfan, if you still need it, here is the layout of my device that usesoPossum's scheme (see attachment). It was necessary to make it as small as possible and so the PCB dimensions are only 29x13mm. Here's what it looks like (made two units for CPU and case intake fans):Capacitors and resistors are smd 1206 type. The Ground line should be made on the opposite side of the pcb, or Ground points can be connected with a wire.The device works fine - tested with some 120mm and 80mm fans.oPossum, thanks for a simple and great scheme!

author: hur
author_rank: Newbie
timestamp: July 06, 2013, 03:40:27 pm
content: Quote from: oPossum on November 19, 2010, 01:34:58 pmI just built this. Works great I am running Two 350mA 120mm 2600rpm fans with it.I am using TIP42G and 1/4 watt resisters. TIP42 is heating up.Am I using too many Fans?