Help: More power to USB

nodger

I wasn't sure where to post this, but this seems like a semi-relevant forum. Apologies if it's off-topic.

I bought a USB module for my car stereo, which allows me to connect external storage devices like USB keys, HDDs, etc. The problem (I believe) I have encountered is that the USB drive (a Western Digital Passport 60GB) is drawing more than 0.5A from the module, which is a no-no in terms of breaking the USB specification.

The USB drive has no auxilliary power input, and the stereo USB module only has one USB output. Does anyone know of a device that i can attach in series with the single USB cable, so that I can get more power to the drive?

Cheers.

ZENER

Hi Nodger, The specifications for USB powered devices says that they can only supply up to 500mA as you say yet I've come accross many USB devices - like your HDD - which clearly demand more. Your WD Passport needs up to 1A according to it's spec so maybe WD know a different set of specs for USB.

I checked out some powered USB hubs in the hope that they might provide more current but they all seem sketchy about their capabilities.

My portable drive (Freecom II 40GB) comes with 2 cables, the first is a USB <> USB Mini connector and the second is a USB <> Power connector. The notes for it say the second cable is in case the USB port in use cannot supply sufficient current then 2nd USB port (2 x 500mA = 1A) will be able to. Does your drive offer this facility ? If so maybe you could rig up a USB Powered Hub powered from the Cig lighter or some other way and attach 2 USB cables to the drive. Not elegent I know, but a workaround.

Otherwise I'm afraid you might have to get on to the maker of the USB device for help. Would you mind telling me or providing me with a link to the device, thanks, sound interesting.

ZEN

Breezzzzze

My guess is that it's not a power issue at all. I have an MP3 car stereo that takes MP3 CDs, SD cards and USB drives. It will work with pen drives but not 2.5" portable hard drives. Previously, I had a little gadget that plugged into the cigarette lighter and broadcast the MP3 files to the car radio. This also would only work with pen drives but not portable hard disks. I remember trying three different drives, but without any luck. It seems the pen drives use a simpler software / firmware that is compatible with more gadgets.

decob

Breezzzzze wrote:

My guess is that it's not a power issue at all. I have an MP3 car stereo that takes MP3 CDs, SD cards and USB drives. It will work with pen drives but not 2.5" portable hard drives. Previously, I had a little gadget that plugged into the cigarette lighter and broadcast the MP3 files to the car radio. This also would only work with pen drives but not portable hard disks. I remember trying three different drives, but without any luck. It seems the pen drives use a simpler software / firmware that is compatible with more gadgets.

bit of a contradiction there with your statement, no? did you not consider the reason that your 2.5" portable drive wouldn't work with your stereo was due to it not getting enough power. like another poster said, it's a common enough problem with some portable drives.

Breezzzzze

No contradiction.

The lighter-socket powered device didn't use USB at all! In fact, you can power a small TV set, compressor for pumping your tyres etc.. from the cigarette lighter socket so power isn't an issue here.

Also, I didn't mention that the supplier of the same device said that it wasn't compatible with 2.5" usb drive firmware. I did an internet search and found that this is the case with a lot of other devices.

Do your own search and you'll find the same info.

BostonB

Breezzzzze wrote:

No contradiction.

The lighter-socket powered device didn't use USB at all! In fact, you can power a small TV set, compressor for pumping your tyres etc.. from the cigarette lighter socket so power isn't an issue here.

Also, I didn't mention that the supplier of the same device said that it wasn't compatible with 2.5" usb drive firmware. I did an internet search and found that this is the case with a lot of other devices.

Do your own search and you'll find the same info.

I'm confused if it didn't use USB how did it connected to USB drives?

Blowfish

BostonB wrote:

I'm confused if it didn't use USB how did it connected to USB drives?

I think he means it didn't use USB for power.

BostonB

ZENER wrote:

Hi Nodger, The specifications for USB powered devices says that they can only supply up to 500mA as you say yet I've come accross many USB devices - like your HDD - which clearly demand more. Your WD Passport needs up to 1A according to it's spec so maybe WD know a different set of specs for USB.

I checked out some powered USB hubs in the hope that they might provide more current but they all seem sketchy about their capabilities.

My portable drive (Freecom II 40GB) comes with 2 cables, the first is a USB <> USB Mini connector and the second is a USB <> Power connector. The notes for it say the second cable is in case the USB port in use cannot supply sufficient current then 2nd USB port (2 x 500mA = 1A) will be able to. Does your drive offer this facility ? If so maybe you could rig up a USB Powered Hub powered from the Cig lighter or some other way and attach 2 USB cables to the drive. Not elegent I know, but a workaround.

Otherwise I'm afraid you might have to get on to the maker of the USB device for help. Would you mind telling me or providing me with a link to the device, thanks, sound interesting.

ZEN

The problem is not the 2.5 enclosure, but that some 2.52 Hard Disks simply need more power than "some" USB ports can provide. Also not all USB ports supply power or supply enough power. Some 2.5 externals used to come with a "Y" cable USB or a cable to plug into a keyboard to draw off extra power. I've a couple of Western Digital 2.5 80GB drives and I've only ever used one USB cable with them.

Look for something like this
http://www.bixnet.com/5vps2powercord.html
http://www.cyberguys.com/templates/searchdetail.asp?productID=7473

BostonB

Blowfish wrote:

I think he means it didn't use USB for power.

Well he said "didn't use USB at all!" so how did he connect a pendrive to it!

Blowfish

BostonB wrote:

Well he said "didn't use USB at all!" so how did he connect a pendrive to it!

He was thinking about power and so phrased it badly

BostonB

Breezzzzze wrote:

My guess is that it's not a power issue at all.....It seems the pen drives use a simpler software / firmware that is compatible with more gadgets.

They simply use very little power.

blastman

Pen drives are generally formatted to FAT16 (usually just called FAT). Larger devices like portable hard drives are formatted to FAT32 as there is a 2GB limit with FAT16. Some devices that have a USB slot can't read FAT32 devices. This may be the problem also.

BostonB

blastman wrote:

Pen drives are generally formatted to FAT16 (usually just called FAT). Larger devices like portable hard drives are formatted to FAT32 as there is a 2GB limit with FAT16. Some devices that have a USB slot can't read FAT32 devices. This may be the problem also.

Thats true. I still think low power is more likely though.