Banana pi R3 fan with PWM

Hello, What type is the 5Vport for FAN?

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Can you recommend a fan to fit for this device with PWM?

Thank you in advance.

If you are looking into any fans, you should look for GPU fans, as industrials are rarely PWM controlled.

Personally I am planning on salvaging a heatsink with a fan from a motherboard south bridge.

You will have to make your own cable.

I intend to use this:

And obviously I have to create a cable but what type is the fan ports on banana pi R3. There are 2 ports with 2 and 3 pins.

Afaik north/southbridge have only ~35mm holespacing (see some with totalsize 38x38 on ebay),so not the 43mm we need for r3. Some gpu-heatsinks seem to have the right holespacing,but most are too long (~100mm will go over antenna connectors),here we need a max of 80mm. Of course we can spend each chip an own small heatsink,but i still search for 1 for all :slight_smile:

For inital question: fan connectors are both micro jst ph (2mm pin spacing).

For electrical connections afair middle pin is gnd, pin to 2pin-connector is pwm,the other (to gpio header) is 5v

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The schematics explain it the best if you ask me:

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Gnd is clear there,but it is not clear which pin is 5v and which is pwm. Up in shematic does not mean up in layout. Maybe by pin-numbering which needs additional research,i don’t see pin-numbering or a “start” marker (like for gpio header) on board.

The order of the 3-pin connector is like it is shown in the schematics. Just use multimeter to find VCC and then GND is middle PIN.

There are absolutely no problems to feed the fan from the VH3.96 12V power connector, thus making less trouble finding a 5V one.

That noctua one is way too thick. South bridge coolers seem to be suited. Try searching some PCH coolers.

I found the sucker! :champagne:

POWER-LOGIC-1 POWER-LOGIC-2

Don’t order the 3pin one, it is wrong. 3pin fans wired are hot, ground and rpm tach pin, no PWM sense pin.

Only 4 pin fans have sense pin to drive the fan speed.

Driving a 12v fan with pwm which should always be 5v ttl sounds strange. And using 5v for the fan itself will not work…would be great if someone finds a full 5v variant. Till then i odered a passive heatsink which gets the 4 holes manually

It is actually usually 5V TTL in motherboards, fans differ for sure, some are less tolerant driving them from 3.3V, it also applies to higher voltages, some cannot be driven with 12V pulse you have to look in the FAN datasheet.

An example.

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Can this fan be driven with 5v (pwm and vcc)? Have not found yet a datasheet for MGA5012XB

MGA5012XB is a two wire fan. It cannot even find a variant having tachometer, yet a PWM version.

PC motherboard 4pin FAN header, the heck even industrial 24V DELTAs, most of them are compatible and can be driven with a 5V PWM signal, there usually is nothing else and that’s a standard practice.

So 5V or 12V doesn’t matter as long it has PWM sense pin. The fan itself should be internally correctly terminated with appropriate voltage divider, to remain correct function if the wire ain’t hooked up.

That my example item should work fine. Just need make a nice cable… After football should look for cheaper deals.

I got the fan part number from the item you linked (below stands 4pin). It does not need to be cheaper (~11€),but 2 months for delivery is long (germany in my case)

I’m using small aluminum sinks for the chips and 120mm fan mounted on the lid of the box. Currently the fan is powered by USB port, but I intend to order this: NF-F12 5V PWM (noctua.at) which is 5v and to connect it to fan header. Any suggestions about my choice?

Is there a smaller version (at least 80)? 120mm is huge and may take much place in case if it will fit.

My current plan is similar (separate heatsink for all chips and fan on case if needed)

The fan is mounted outside on top of the case lid. Bigger fan and low RPM… it’s very quiet which is important to me.

Ordered one. I am from Latvia, so pretty much in the same boat, but things do ship faster recently. Like two weeks, so it ain’t that bad.

I will report here my results and looks.

Ordered which one? :slight_smile:

The one I linked. 4pin ofc.

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