PC Card experts...a question...

[CanuckAmok]

Okay, so I just shelled out BIG bucks for a LaCie pocketdrive. Their website stated that the drive is bus-powered through a IEEE 1394 (FireWire connector). Besides the huge storage capacity and buffer rate, the self-powered feature is the reason I chose their drive over their competitors.

So NOW that it's arrived, I find that the unit can only be bus-powered via a SIX PIN IEEE 1394 connector. Of course, my laptop, like nearly every other laptop in the PC universe, has a FOUR PIN IEEE 1394 connector. So, I have to use the optional AC adapter with my LaCie drive, which sort of defeats the point.

I've looked on-line for PC card (PCMCIA card) six pin IEEE 1394 cards, and there are many. However, I don't know if they can tap into the battery on the laptop and power the LaCie drive.

Can anyone tell me if there's a way I can install a powered SIX PIN FireWire connector into my laptop? Or, can anyone point me in the direction of a FireWire PC card which has bus-power on-board?

[Kellanved]

1. that might be a problem

All PCMCIA (PC-Card; I just like the old name) Firewire adapters I know require an extra power supply for non-self-powered devices. There are 6-Pin cards, but those come with an extra PSU.

[CanuckAmok]

2. Damn, that's what I'm finding, too...

I wonder...my laptop has both the four pin 1394 FireWire connector, and a few USB2.0 connectors. I know that USB carried electrical current--is there a device which can tap the power of the USB and route it to the FireWire?

[Kellanved]

3. hmm

I don't think so; AFAIR USB allows ca. 2W ; Firewire well over 40W. And many notebooks even need a powered USB hub for devices like scanners.

Edit: removed one "remember"

[CanuckAmok]

4. Hmmm again...

I just looked at the AC adapter which came with the LaCie drive, the output is 12V DC @ 1.2amps.

1.2 amps isn't alot of power...I wonder if that much can be drawn from either the USB or card slot...

[Kellanved]

5. well

that's 14.4W. More than an USB port can handle (if the above numbers are close to reality - I'm not 100% sure)

I'll look into the USB specs and update the info.

Edit: I was pretty much on target: up to 500mA (but can be as low as 100mA) at about 5V+- 0.25V; 2.5W maximum .

Edit2: PC-Card is out as well; 3.3V @ 1A . (not 100% sure, I don't have the specification). Most systems should supply 5V and 12 V as well, but with lower currents.