Problems powering up VK204-25

LK/ELK/VK/PK/OK/MX/GLK/EGLK/GVK/GLT Series

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luimarma
LCD?
Posts: 3
Joined: Wed Jul 05, 2006 6:27 am

Problems powering up VK204-25

Post by luimarma »

Hello,
I am using Matrix Orbital VK204-25 displays for my aplications. Recently I have changed for the standard model to the one that uses 12V for power. Whenever I turn on my system the display stays unpowered or it does not work properly when the computer starts to send commands (Both PC and display are powered up by the same power supply)
To make the display work, I need to unplug and plug the power from the display before the computer starts to send data, if I am too late I get a garbled screen on the vfd. After doing this trick the display works correctly.
Is there any way to solve this?
May a condenser between the power pins of the display be a solution? If so, which value should be OK?

Regards,

Luis
Jon
Matrix Orbital
Matrix Orbital
Posts: 231
Joined: Mon Oct 24, 2005 10:38 am
Location: Calgary, AB, Canada
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Post by Jon »

Hi Luis,

VFD's such as the VK204-25 are quite power hungry at start-up. If it would be possible for you to post a picture of your display module, we would be able to check the revision of it, as well as pinpoint the the location for you to check the voltage that it is receiving when your computer powers up.


However that said, it is odd that the VK204-25 would work, and the VK204-25-V does not, because the VK204-25-V is run with a regulator, it should be even more reliable.
luimarma
LCD?
Posts: 3
Joined: Wed Jul 05, 2006 6:27 am

Post by luimarma »

The revision is 1.23.
The thing is that when I changed from using 5 to 12V y also changed the power supply of the system that now has a 12V output.
It is strange that I have not enough power at start up, since all the power requirements for the devices I use are far low from the power supply specs, and I have left 3A for the VK204-25 that is the only 12V device that I use.
Can a conderser between the VK204-25 power pins be a solution to delay the power up of the display?

Thanks in advance,

Luis
Jon
Matrix Orbital
Matrix Orbital
Posts: 231
Joined: Mon Oct 24, 2005 10:38 am
Location: Calgary, AB, Canada
Contact:

Post by Jon »

Hi Luimarma,

Have you had any success solving this problem yet? You may try using a capacitor to delay the power up, however you will have to play with the value depending on how much delay that you want.

Please let us know if you are making any progress.

Note: If you are attempting this, you must have electrical knowledge because if you are not careful you could ruin the display and this would not be covered under warrenty.
luimarma
LCD?
Posts: 3
Joined: Wed Jul 05, 2006 6:27 am

Post by luimarma »

I will post my tests as soon as I make them.
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