power supply to HD (IDE 3.5")

peterlonz

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Sep 19, 2010
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MY 3.5" Ext HD has both USB & a power port.
The power port is not marked with required voltage, but I assume it needs 12VDC.
Problem is the female connector on the enclosure has a multi pin circular arrangement.
I do not recall seeing this type before associated with PC hardware.
What is it called & where might I buy such a cable?
 
Solution
A photo and model number would be helpful. I have seen some really odd ones in the past...

like this:
Mini-DIN_male_4-pin_power_connector.jpg
Old hard drives most likely require 5 and 12 volts. I have multiple power supplies like that, but they are not always the same. Do you have no diagram on the back of the drive or anything?

Some of these units can be opened and you can follow the wires/traces to the drive to see what pins do what.

I think the connectors are called "mini din"
 

peterlonz

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Subsequent Google search indicates the connector is a "6 pin round DIN".
I am pretty sure it's not a mini.
There is no marking to indicate voltage, function on the enclosure.
Inside there are 4 wires: 2 x Blk, I x yellow, & 1 x red.
So I am guessing I could wire up the red & blk for a 12vdc supply.
I know the voltage supplied by each colour.
My PC does not have such a connection anywhere so I am baffled as to how I ever had it working on just the USB supply?
 
Yep four pins on the power connector.

One will be a 5v+ feed The other will be a 12v+ feed.
Then the two pins left on the power connector will be negative -

But you will have to work out how + and - are wired.

If you have a digital multi meter you can do this by unplugging the power port from the wall.
And setting the digital multi meter to it`s continuity test setting.

Where it will beep then the red and black probes are touching two out of the four pins you see.
And tell you if there is a complete circuit.

Once you have the pin layout from + to - and the pin orientation.
You can set the multi meter to a DC setting.
Plug the power adaptor into the wall socket and.

Work out what is the +5v pin and the +12v pin of the adaptor end.

As the multi meter will tell you based on what colour probe is touching the two pins on the display of the meter it`s self if the voltage is + or -.

If minus reverse the probes toughing the two pins if it shows plus + then looking at the colour of the probes you know what the + voltage, and - pins are, and in what position and order voltage polarity is wired for the power connector.

peter.


 

peterlonz

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I think yellow & black says it all.
I intend to direct wire from my 12 VDC adapter (with coaxial plug on the output) into the ext HD.
Should be a simple solder job, although I may find some suitable pin connectors that would allow disconnect without de-soldering.
Now the question why on earth is this connector used, is the 5 vdc required for any reason. Maybe the unit requires two sources of 5 VDC?
 
The unit DOES require 5 volts to work. So you would need a regulator to feed 5 volts as well.

I am not sure if the USB to IDE board needs 5 volts(it can get 5 volts from the usb port), but the hard drive sure does(and more than a usb port is good for).

If you look at the sticker on a 3.5 inch hard drive, they require both 12 and 5 volts. If they are 2.5 inch drives they generally run only on 5 volts. I have 2 drives that take only 12 volts and have a small dc-dc converter to get 5 volts(I like this because the power supply is easy to replace.).