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jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 10:15pm 08 Aug 2014

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Hi
My Son got a new Motherboard for his PC and decided to add a new case and water cooling while he was at it. This lead to him purchasing some new high quality fans. the fans he purchased were 4 wire fans (PWM controlled) but the new motherboard controlled the fans via voltage not PWM (Except for the PCU Fan) so time to breakout the Micromite and make a Voltage to PWM converter.

This what I came up with it is installed in the new PC and working like a charm
I used a SATA connector for the power as this has a 3.3v to power the Micromite.
The basic program is attached. The PCB will fit into a 3.5' hard disk bay so it can be mounted easily.

Excuse the stupid type O (PMW)

2014-08-09_081049_FanCtr.zip

Regards
Jman

WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2927

Posted: 10:37pm 08 Aug 2014

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Another brilliant use for the MicroMite

I have had a quick look at your circuit (in zip file) and also at the photo above. I understand everything in your photo on the right hand side from the two sets of 4 white connectors. However, can you quickly clarify a few things:

I assume the SATA connector is the black connector on the left hand side?
What is X1 for?
Are the three white connectors (1+2) above X1 for the voltage inputs? If so then why not four?

Sorry if these seem like silly questions; especially as you have been working on this for a little while. Like I say, I just glanced at it and have a use for something similar and hence the real interest.

Thanks for posting your project . . . . .

WW

jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 10:47pm 08 Aug 2014

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@WW
X1 is there if you want to use a normal Molex hard drive power connector
you will also need to fit the 3.3v Regulator

Yip the SATA connector is the black bit on the left (Through hole version)

The voltage inputs are the 4x 3pin connectors the outputs are the 7x 4pin connectors
Channel 1 has 3 outputs
Channel 2 has 2 outputs
Channel 3 and 4 have 1 output each

The 4pin connector closet to the 3pin connector also supply's the tacho pulse

Regards
Jman

BobD

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Joined: 07/12/2011
Location: Australia
Posts: 935

Posted: 11:17pm 08 Aug 2014

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John

what brand and model was the mother board that your son used?

have you considered putting a usb connection to the board and permanently wiring it back to the PC to allow setting the fan speeds via Tera Term or other?

edit: delete the second question.

BobEdited by BobD 2014-08-10

jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 11:25pm 08 Aug 2014

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@Bob

The motherboard is an Asus Maximus VII Hero
It came with a real nice GUI application that controls the fans
so he using that to talk to the Maximite etc..

Screenshot below

Regards
Jman

kiiid

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Joined: 11/05/2013
Location: United Kingdom
Posts: 671

Posted: 12:37am 09 Aug 2014

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Datasheet

http://rittle.org

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paceman
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Joined: 07/10/2011
Location: Australia
Posts: 1329

Posted: 02:18am 09 Aug 2014

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Nice looking board John - we'll forgive the PMW instead of PWM

Greg

viscomjim
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Joined: 08/01/2014
Location: United States
Posts: 925

Posted: 04:38am 09 Aug 2014

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Hi Jman,

Took a quick look at the zip file and program. Very cool! What program do you use to do your pc boards? Also in line 13 (not including blank lines) of your code it says

PWM 2, 25000, 10, 10

should that be PWM 1,25000,10,10? or am I not getting it?

Again, nice unit!

jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 10:52am 09 Aug 2014

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viscomjim said Hi Jman,

Took a quick look at the zip file and program. Very cool! What program do you use to do your pc boards? Also in line 13 (not including blank lines) of your code it says

PWM 2, 25000, 10, 10

should that be PWM 1,25000,10,10? or am I not getting it?

Again, nice unit!

@ Viscomjim

Well spotted "You are getting it perfectly"
It should read "PWM 1, 25000, 10, 10 "
That brings the fans down to dead slow after the initial spin up

I use DipTrace for my PCB's

Thanks for comments

Regards
Jman

jebz

Regular Member

Joined: 13/06/2011
Location: Australia
Posts: 79

Posted: 12:11pm 09 Aug 2014

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Geoff has a good fan controller project at -
http://geoffg.net/fancontroller.html
Both projects have some nice features.

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