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14pin vs 16 pin 20x2 character backlit LCD?

I am trying to replace a 20x2 character LCD in a piece of gear that I own. It is a Data Vision DV-20200, S1MBLY LCD, here are the specs:

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I don't know exactly whether I have an TN, STN, EL or whatever, but I'm almost positive it is backlit; although it is NOT this unit, it looked exactly like this when it was working, yellow backlight and all:

formatting link

Now for my problem - my existing broken LCD has only 14 pins, whereas every replacement one I've seen has 16 pins. As I understand, those last two pins are the ones that supply power to the backlight.

Is it possible that I can have a backlit LCD with only 14 pins? And if so, where can I find a suitable replacement?

Thanks, Dan

Reply to
Dan Nigrin
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Hi Dan,

Dan Nigrin schrieb:

Dysfunctional site, so I can't say anything on this one.

On most 16pin "industry standard" LCD modules pins 15 and 16 are more or less directly connected to A and K you see on the right of that picture. Of course this only applies to LED backlights, not EL!

Sure. There must be A and K terminals then. Just wire them up, but try a 470 ohm resistor in series first.

You can use any of these displays you can get, if it is same size and character/lines number. But take care: there is some sort of contrast control voltage (V_lcd, pin 3). Usually, this voltage is between 0 and +5 Volts. Sometimes there are LCD modules which want a negative contrast voltage. Mostly these are modules for an extended temperature range. It is best to measure what voltage you have on pin 3 and then pick a suitable replacement.

HTH Wolfgang

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Reply to
Wolfgang Mahringer

Many manufacturers offer these modules, and 99.9%, are directly compatible (using 'clones' of the old Hitachi controller chip). Most offer different pinout options. So (for instance), Powertip, offer the 'PC1602-H', with a

16 pin conector, or the 'PC1602-I', and the 'PC1602-J', both with a 14 pin DIL connector. Then you have versions with 14, and 16 pin SIL connections, above, and below the display. In many cases, the 14 pin version has been dropped, since you can just use the lower 14 pins, and not connect to the top two pins, with the seperate backlight connection at the other end of the board. Also some of the newer modules offer a jumper/solder pad, to power the backlight (only on LED backlit versions), from the 5v connection feeding the logic. Some, have the 16pins, but don't bother to even make the upper two connections. Have a talk to somebody like CrystalFontz, and they should be able to do you a version of the CFAH1602, that runs from a single power connection.

Best Wishes

Reply to
Roger Hamlett

Thanks for the info, very helpful! I will get in touch with CrystalFontz.

Dan

Reply to
Dan Nigrin

Thanks for the information!

Dan

Reply to
Dan Nigrin

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