Powering drive through double usb to molex cable HELP

vbimport

#1

Im currently working on making a completely portable xbox 360 hacking computer. ive got a laptop with a compatible pcmcia card chipset and all the tools i need but i just need to power the drives. I was figuring a double usb to molex cable would solve this problem since the power specifications ont eh drive show 5v - 0.9A. but im slightly confused. does the drive ALSO require 12v - 1.2A or is this just another specification for 12v power? if so do i still have to have the 12v power pin in the molex connected or will the 5v alone work? i just dont in specifics how drives draw their power.

P.S. For those of you in the know, i do know that the xbox360 drives do NOT have a molex power on them. I am using a Maximus connectivity kit which powers the drive and has a molex input.


#2

Hi,

the power requirements of any given optical drive is normally printed on its label. If the label states 0.9A @5V [B]and [/B]1.2A @12V then it needs both.
In any case, you need a separate power supply unit to feed an external optical drive. An USB port is specified to provide 0.5A @5V if requested by the device, one of these non-spec Y-cables will give another 0.1A only.
In case a Cardbus (PCMCIA) controller card is used, these don’t even provide the 0.5A @5V unless some additional power is fed to that controller (that’s why they have an input connector for additional power supply).

Michael


#3

how come making a double ended cable will only provide another 100 mah? will two ports not both output 500 mah? ive made a double ended usb power cable for a few other things like an external slim drive and an external hdd and both work great. and its doesnt say on the label of the drive that it requires both, it simply lists them like this

5v - 0.9mah
12v- 1.0mah


#4

Hi,[QUOTE=spankmaster;2462486]how come making a double ended cable will only provide another 100 mah?[/quote]This is by spec. An USB port delivers up to 100 mA without request by the connected device. To deliver more then 100 mA (up to 500 mA), this must be requested by the device. The second “leg” of such an USB-Y-Cable is only power, no data.

and its doesnt say on the label of the drive that it requires both, it simply lists them like this

5v - 0.9mah
12v- 1.0mah
These are the requirements. That device needs 1 A @12V [B]and[/B] 0.9 A @5V

Michael


#5

[QUOTE=spankmaster;2462386]Im currently working on making a completely portable xbox 360 hacking computer. ive got a laptop with a compatible pcmcia card chipset and all the tools i need but i just need to power the drives. I was figuring a double usb to molex cable would solve this problem since the power specifications ont eh drive show 5v - 0.9A. but im slightly confused. does the drive ALSO require 12v - 1.2A or is this just another specification for 12v power? if so do i still have to have the 12v power pin in the molex connected or will the 5v alone work? i just dont in specifics how drives draw their power.

P.S. For those of you in the know, i do know that the xbox360 drives do NOT have a molex power on them. I am using a Maximus connectivity kit which powers the drive and has a molex input.[/QUOTE]
Hi i am also doing this and i now have it all sussed on the power connecter for the dvd drive it uses 12v, 5v, 3.3v and GND for the 3.3v you need a 3A low dropout voltage regulator to go from 5v to 3.3v then you will need a step up voltage regulator to get your 12v from the 5v usb (probably using 2 usb’s) i have already made the molex to xbox dvd drive converter just waiting for parts for the usb to molex converter let me know if you want any help :wink: