CardBus (PCMCIA) USB 2.0 device polarity

Those Chinese AKE brand CardBus USB expansion ports, discussed ad nauseam earlier in closed threads, are tip positive. I just sweated as I plugged in 2 amp 5 volt universal power supply, my ipod and a USB hard drive. A story of more power, as the CardBus specifications are for 400 mA, good for USB thumb drives and bluetooth, but not charging or spinning devices.

 

Yes.... The AKE cards will run a USB key great... But if you need to plug in an external 2.5" external drive... You'll need two USB ports to power it... So you will need to rig the (hopefully) included cable from a spare factory USB slot to the power port to the USB card to supply the needed 5 volts.

The external hard drives need one USB cable for 5V power and the other for data flow. USB keys don't need the extra 5V so they can operate off the card without the cable.

 

Naw, my Western Digital USB drive has a Reduced Power Spinup specification so it doesn't require the typical 1 amp,1 second startup of 2.5" hard drives; so one USB plug is all it needs.

 

Good luck and keep us posted....

 

rrick -

The prob is not the current, but rather the limitation of the PCMCIA slot itself - it puts out only 3.3V 500ma, whereas the spec for USB is 5V 500ma PER PORT.

Now these guys use a itty-bitty inverter on the board (I've opened it up) which works fine for thumbdrives & such; but even for "USB-friendly" drives it's not enough... I toasted one card finding that out.

Hope you have a spare card... you're gonna need it.

mnem
*Places sign of the cross on rrick's workbench*

 

I gave up on the usb powered external hard drives
I used them to store and transfer files between computers
I had issues with power serges and lack of required current output on some computers
The solid state storage devices that I use now are universally compatible with all computers that I have used as they draw less current


Alex

 

Sorry for any confusion. I just wanted to add the little USB to ring and sleeve cable they include is tip positive. I got me a universal power supply, which included the same ring and sleeve connector, set the wall wart to 5 volts, plug and prayed it was tip positive and inserted it (along with a full amps worth of accessories). It worked!
Hey Tomcat57 check out the WD drives with the RPS function mentioned. WD's white paper states the function reduces the 1000 mA spinup power surge to less than 100 milliseconds opposed to 1 second typical. Still is there, but very short. I only found out about that proprietary capability when I searched to see if I can swap it into the Toughbook caddy. Result: vent holes don't line up with the OEM drive/caddy and more importantly, the USB controller is integrated in the drive itself in the newer portable drives.

Did anyone think I pulled 5 watts from a 1.3 watt connector and lived to tell the tale? Great to hear the inverter was taken care of. I sweated the first time a USB key was plugged without the power connector in too.

 

Don't trust those PCMCIA adapter specially those made in china. You've luccky if you could use that for one day without a problem. It doesn't even inspected by quality control inspector. Yah! you can see a tag with QC but it is not the reality.


ohlip

 

I seemed to have touched a nerve with the AKE devices, but you all understand I was just contributing a polarity answer to the files, if you wanted to power both CardBus USB ports to full power with an external power supply.
I am realizing, thanks to your input, the second I loose wall current to that AKE device, and the inverter takes over, I'm fried, and out of $13 for the next one.
It is just the Toughbook50 fell out of my lap with USB devices plugged in and landed there and broke the internal connections on both Panasonic USB ports.

 

Sorry! to heared that, man! I'm with you since you don't know yet what trouble will gonna give you those crap accessories.

Since the beginning I've seen those crap, I'd never trust those as I know for the fact that these item was made without proper designed, control, inspection or testing for certain period of time. But as you can see on ebay they still buying a toughbook with all those crap not reliazing in two to four days period it will start the true value of those crap, Lol.

Again and again, this is to remind those who are planning to buy a toughbook unit with all those crap! Beware.



ohlip

 

Yeah, here is the damage. Two diodes and two coils. Only a trip to Heartland can save these original ports.

 

Yeeeowch...

Prolly be less expensive to hawk Fleabay until you can find one with a smashed LCD to rob the MB from...

mnem
Ahhh... the joys of Toughbook ownership...

 

Whoh, woah! Scraping off those components left me a dead computer. Apparently there was some meaningful connection that would have failed on the first ajar. But, none of us prescribe to the - leave it alone mentality-, so its not a problem. The cf-50 did have a nice, easily readable screen and I was ready to eBay my 52, but... Pop that good'old badboy that served me 7 years in to the storage. Time to focus on the computer that will host my iPad!!! 'nuf wid da multitaskin' distractin' operating systems!