633 USB power supply

[srg]

Can anyone help me?

I have bouht two 633 with USB interface. I want to install them outside the PC tower, so I would like to feed them trough USB. In other words, I don't wan't to send an adittional power supply cable from the PC to the LCD, only the USB cable WRUSBY03.
Is it possible to do this?
Will the backlights work?
Must I change any jumper on the 633?
Must I do any change over the PCB of the 633?

If it isn't, Can I connect an external power supply to the LCD? Any problem with different GND from the USB interface and from the external supply?

Thanks a lot and sorry for my English.

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[srg]

PLEASE HELP ME!

PLEASE, HELP ME!

The, I'm afraid there is a problem with the LCD or with the installation. I'll explain you the installation process I have done in order that you can help me.

I connected the 633 USB to my computer trough WRYSB03 only, with no power supply power. After that I installed succesfully the USB drivers. Theoretically everithing was OK but I could´t talk to 633 trough Crystalcontrol or Wintest. The LCD seemed OFF because no backlight was ON.

Then I connected a 3_1/2 inch floppy powerr supply able to the "PWR" connector of the 633 (next to FAN2 connector over the PCB) and everything was ON: the LCD backlight, the buttons... and I could talk to 633 without problems using Wintest and CrystalControl.

Do you know where the problem is?

Lastly, I tell you that for my project no additional connections are neccesary: I don´t want to connect any FAN of ATX power supply control. I only want the 633 USB LCD as a remote console with its LCD and its six buttons.

THANKS IN ADVANCE.

 

[CF Support]

The 633 requires the floppy drive power connection to supply the power for the backlight and logic by default. The USB is only for the serial communication.

 

[Voltaic]

Really, so the LCd is not powered by the USB power. Why is that? I was hoping to find a cheaper alternative to the MO LCds, but their USB LCDs can take the power from the usb line.

Is there an easier way to, perhaps, take the Blue/White/Gray 633USB and Buy/Construct a custom cable that would supply the USB and Power feed, so as to create External LCD shells?

 

[CF Support]

I think you'll find that any USB LCD that controls fans will require a separate +12v supply. The USB can only supply 500mA at 5v, which is not enough to drive most fans.

The CFA-632 and CFA-634, as well as the CFA-631 can run using only the power from your USB port, so if that's the way that you want to go, there are 3 options.

I imagine there are enough conductors in CAT5, but you'd have to be concerned with whether or not it's "safe" to run +12v through the CAT5 cable for your backlight and fans. The CFA-633 can be set up to power the *logic* through the USB, as that +5v supply is more than ample for the logic itself, but not for the backlighting + fans, etc.

I'm sure there's a way to create a custom cable to run power and everything to the CFA-633, but the main question is having the conductors in the cable adequate to the task.

 

[Voltaic]

Well, my primary needs are the Backlight and Logic. If you're saying both of those need more than a 5v line.. Hmm..

I'll look at the other ones. Thanks!

Edit: YGPM.

Looking at the 631, is it possible to buy the 631 W/Buttons, W/O Frame, just wanting the LCD itself? It looks like almost exactly what i'm wanting... It just has a useless aluminum frame.

 

[CF Tech]

Some more detail

The CFA-633 yellow can be strapped to operate from +5v only, powered by the USB.

This configuration is not a standard product but it is possible. We have to change the LED dropping resistors, so there is usually a slight additional cost involved.

By default, the logic is powered from the +5v floppy connector, and the backlight (yellow and blue) are powered from the +12v floppy connector.

The CFA-633 blue does need the +12v for backlight, but can operate its logic from the USB with special strapping.

 

[CF Support]

YGPM Voltaic