Matrix Orbital Corp

Hi,

I have a VFD2041 (PCB V1.5) that I haven't used for some time. I'm not sure if it's working - should it be blinking as soon as power is applied to Vin & GND?

Thanks.

Hi Madlan,

The default startup state for a VFD2041 is to show a start screen with no cursor. However, these defaults may have been changed, including the start screen which can be made blank.

If the unit has been sitting for some time, I would recommend resetting it to defaults and attempting to send some text. The PCB Rev1.5 version of the VFD2041 has hardware jumpers for communication protocol selection, so please check those settings, set your host to match, and try sending some data.

Unfortunately, that older revision does not have a power LED, so if your start screen is blank and you are unable to send characters, you'll have to monitor the current draw of the display to determine if it is powered correctly.

All the best with that older unit; if you have any further questions regarding that display or perhaps purchasing a newer model, please don't hesitate to ask.

Thanks,
Troy

Hi Troy, thanks for your reply. Could I ask how you reset this model? I see the newer one has a jumper to reset it?

Also, how do I identify the wide voltage range model? I'm powering the unit with 5v and have it connected via RS232 (Serial, COM1)

Hi Madlan,

Manual override is a great feature, but unfortunately it is one that we added sometime after your PCB Rev1.5 was released. You'll be able to set baudrate and communication protocol manually which should be sufficient to allow you to at least query the display for a module revision to determine if it is communicating correctly.

As for the input voltage requirement, please take a look at the electrical connection image for your display on page 3 of the manual. Above the red, 4pin power header is a small metal rectangle surrounded by circular vias, and bounded by a square of 4 holes in the PCB. If there is a large PCB mounted using the 4 largest holes, your unit is a -VPT model. If the small metal square is populated with a black regulator IC, your unit is a -V model. If no components are populated you have a regular voltage unit.

Thanks,
Troy

There is a 78M05 voltage regulator, does that mean 12V?

Here is a picture:

Hi Madlan,

I appreciate the image provided and can confirm that you do have a -V unit. Typically, this is a 9-15V input, but please consult your manual for the most accurate specifications.

Thanks,
Troy

Hi Troy, the display is now working perfectly!

Could I ask, is there any other difference with the -V model?

Excellent!

There are no other changes for the -V model, just the addition of the regulator and supporting circuitry in order to drop the input voltage down to 5V to run the display.

Thanks,
Troy

Hi Troy,

I actually have a regulated switching 5V power source for my project - Would it be impossible to bypass the on board regulator and power the unit with my 5V?

Thanks.

Hi Madlan,

It's not impossible, but it is difficult and definitely warranty voiding. The later likely won't concern you, but for the former you'll need at least basic soldering knowledge and a second iron with a hot air rework station would be a bonus.

Essentially, you'll need to make your unit look like the one shown in your manual. Most important will be to disconnect the 78M05 regulator, either by cutting the leads or removing it entirely, then make a solder connection between the two pads at the bottom of that component. The capacitors on either side of the regulator are only to filter noise on input and output, they are overkill for a 5V unit, but do not have to be removed.

If you decide to do this modification, please be careful, and let me know if you have any questions or concerns.

Thanks,
Troy