Sign in with
Sign up | Sign in
Your question

Help - Power a USB Card reader

Last response: in Components
Share
May 11, 2011 1:40:58 PM

Hi Guys, need help with powering a usb card reader.

I've done a PC table mod, i used a internal card reader as speaker stand.




When i connected it by extending thru ribbon cable (original=1feet, now= 3feet), the PC is unable to detect USB pen drives, & card readers, it shows "USB device unrecognized"



Only XBOX 360 controller works, SD cards fail to connect.


So i understand this is "power supply to card reader" issue, but i want to know how to solve this problem. :) 

Can i connect the 5v header from other (front panel usb port) motherboard USB header to the card reader's?

Is it safe to do so, or would i be blowing the whole m/b? :D 



here's the card reader's image



(edit: imageshack auto rotated the above pic some reason :-\ )

any way to power it externally?

More about : power usb card reader

May 11, 2011 2:43:31 PM

Why do you think this is a power issue rather than a data issue?
May 11, 2011 3:14:20 PM

Have you tried to installing the drivers from the disk you gotten when you purchase from the store or try to get the drivers from the manufactor website?
Related resources
May 11, 2011 3:19:19 PM

this is a generic card reader & i'm using windows 7 (sp1).

this used to work very good when i had it installed in the cabinet.

could the culprit be the new cable itself?

the shopkeeper had only one type of ribbon cable.

how to diagnose?

should i invest on a multi meter?
a b ) Power supply
May 11, 2011 3:33:43 PM

Have one of these and if I remember rightly, its has its own cable to connect to motherboard usb header for data and power comes from FDD molex?

So, if this is the right model, your right, your not getting enough juice.
May 11, 2011 4:39:07 PM

ya, its the similar model, it can be seen on 3rd pic (top right corner =header)

btw i'm not using a direct connection between the reader & pc.

i split (cut) the original cable in half & joined the new cable in between, coz i couldnt find those plastic connectors :D 

so how can i supply more power?

quoting from 1st post- :p 
Can i connect the 5v header from other (front panel usb port) motherboard USB header to the card reader's?

Is it safe to do so, or would i be blowing the whole m/b? :D 
May 12, 2011 9:26:35 AM

If you know the pin assignments and you filter out the power part and redirect that to a different source like an alternate usb port, then basically it shouldn't cause any problems.
Just be 100% sure you got the wires right and not end up crossing two power sources or blowing up your usb controller or card reader.
So get some schematics first.
May 12, 2011 10:14:48 AM



This is in motherboard manual.

so, can i use the second USB headers' +5v (only one) & connect it to the card readers respective wire?

May 12, 2011 10:17:50 AM

that should be possible yeah, just be sure you get the right pin on the reader as well.
As far as the ground connection, imo it's safer also getting that from the header and well.
When fabricating thing this re-route be sure not to short circuit anything!!
May 12, 2011 10:19:15 AM

BTW, what you can also do if you have a external 5v power adapter to hook that one up to your reader.
Again be sure to get the right pin's :) 
May 12, 2011 11:03:50 AM

I have a USB power adapter :D 



http://pinouts.ru/Slots/USB_pinout.shtml


from these pics --

Should i connect the #1 in "A" to 5v header on card reader (1st pin)

then #4 (A) to ground (8th) pin on card reader)

did i understand this right?
May 12, 2011 11:35:32 AM

Yup, seeing those schematics that should be right.
May 12, 2011 12:03:45 PM

didnt work :( 

still shows error :( 


tried to connect both 5v header on reader (one by one)

funny thing is, it lit the usb adapter led light,
so i dont know what happened there, usb adapter was supposed to give power to reader, but it went otther way around?
May 12, 2011 12:08:11 PM

Both 5v header ?
Those readers only rely on a single 5v line if i am not mistaken...
May 12, 2011 12:10:12 PM

btw why not just pickup a cheap external reader instead?
May 12, 2011 12:23:36 PM

thats what i'm gonna do now :(  :p 

I thought something like this workaround could have worked for me

http://www.techenclave.com/networking/how-power-airtel-...
its a tutorial on how to power a wifi modem thru usb

Quote:

"Maybe the mobo is not supplying enough current to the USB ports. You may try using two USB ports in parallel.
a little more explanation about parallel"


get another usb cable like u have already got, join black wire of one usb cable to the blackwire of other usb cable and do the same for red wire .
connect these wire as u have connected in ur pic and try
remember this way voltage(V) remains same but the current increases(A)
May 12, 2011 12:28:54 PM

Ah that explains.
Well seeing that at least you tried but for some reason it isn't working, the easiest way to just pickup an external one rather then make a mistake and blow sh*t up :p 
May 12, 2011 1:13:56 PM

that cable is 2ft long, i need 4ft & also i'm in india :D 

these things are not available here :( 


anyways, are there any external card readers with audio (mic/out) available?
May 12, 2011 1:20:34 PM

hmm not that i can recall
May 13, 2011 3:09:32 PM

Thanks guys, all of you. :) 

dont know which anwser to pick as "best answer" :D 


btw, how to get this thread "solved" status?
May 13, 2011 4:34:26 PM

Choosing the best answer sets the thread as solved.

There are external card readers that have audio connectors but they aren't 3.5 size; they're 5.25 which is a bit of a pain for you if you want it to be part of your desk.

Here's an example.
May 16, 2011 6:09:44 AM

Rusting In Peace said:
Choosing the best answer sets the thread as solved.

There are external card readers that have audio connectors but they aren't 3.5 size; they're 5.25 which is a bit of a pain for you if you want it to be part of your desk.

Here's an example.


"The allinone is installed in 5 1/4 device bay"
May 16, 2011 8:11:16 AM

Yeah I was giving an example of one of these 5.25 drive bays?
May 16, 2011 9:44:43 AM

Rusting In Peace said:
Yeah I was giving an example of one of these 5.25 drive bays?



I gave that remark because he was looking for a external solution, while this type is a build in.
However as i have seen it could be externally used, but then you are gonna loose some functionality due to internal cabling.
!