LCDInfo.com

i just bought a lcd (Optrex DMF 5001NY-LY 160x128 pixels) and i noticed it needed -21 VCC ?? where am i going to get that from(i think there is a -12v rail on my atx power supply).......i intend to set it up via parralel to my computer for a nice little display but....i need information before i even start the project
here are the data sheets http://www.optrex.co.jp/us/product/catalog/pdf_dmf/5001ate.pdf...i what i want is more like a pinout and schematic on how to get the -21 VCC .................}------>could any one help ??

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if i cant mod it ..........NOBODY CAN

btw i have also been through this site and the voltage doublers mentioned here are unavailable to me as i live in Perth,Western Australia
as for the pinouts earlier mentiond by henri earlier........i dont really understand them...................aslo......i am a comlete
NEWBIE at this

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if i cant mod it ..........NOBODY CAN

Few weeks ago I wired couple 5001NY-LY displays and I used two cascaded ICL7662 chips to make the negative voltage from +12V.
ICL7662 costs about 3-4 EUR/pcs here in Finland and needs only few capasitors as external parts.
I think you should be able to find something similar in Australia.

As for the wiring I just followed the datasheet pinout but I guess I could draw somekind schematic of it.

ok..i will check that one out......kudos man.....
one of my friend says i dont need -18 v just 23 volts cause the pda file dosent say any thing about it !!!!!!!!
i know this might be to much to ask
.......the best electronic store here in perth is called alltronics.........do u think any of their cmos ic's would work ?http://www.altronics.com.au/cat.asp?cat=2&grp=10&sort=code....and/or could i simply just use +23v for the VCC ?

You need the negative voltage. The datasheet just mentions the voltage difference needed. Like if you have Vcc of +5v and Vee of -20v then the difference is 25v.
You can't use 23v for Vcc in any case. That would kill the display immediately. I guess this was a typo on your part.

MC34063 could be one solution for your problem:
http://www.altronics.com.au/cat.asp?cat ... 6&id=Z7250

Here is one schematic for -8v using the chip:

It should be possible to modify the resistor values to get higher output.

And here's even a calculator for you that gives the needed component values when you give the input and output voltage wanted.
http://www.nomad.ee/micros/mc34063a/index.shtml

acctually the 23v Vcc was out of my sheer stupidity..i sorryabout that (must have been a good laugh tho ).......i decided ill get the Mc34063 cause i'm goin to the shop tomorow.......

Vin 12v
Vout -18v
Iout 30ma

Ct=NaN pF
Ipk=160 mA
Rsc=1.871 Ohm
Lmin=NaN uH
Co=NaN uF
R1=5.6k R2=75k (17.99V)

what does it mean when it says Ipk=160 mA and Rsc=1.871 ohm

and what would i need to purchase from altronics (component shop) for this circuit and setting up my LCD

sori bout that i keep forgetting to log in.......i'll use cookies this time

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if i cant mod it ..........NOBODY CAN

For most of the component values you can take them from the -8v schematic. So it's for +5v input so you can then use the same +5v as for the lcd.

Parts for -18v circuit:

1 x 16V 100uF capasitor for input
1 x 25V 100uF capasitor for output
of course the capasitors can be of higher voltage rating
1 x 1,5nF capasitor
1 x 0,22ohm resistor
1 x 220uH 100mA inductor or something in the same range
1x schottky diode SB130, 1N5818, 1N5819, 1N5820
and the output voltage setting resistors for -18v:
1 x 5.6Kohm
1 x 75Kohm

also you need a 10Kohm potentiometer or trimmer for the contrast adjustment.

Hope I didn't forget much.

umm.....i thougt i needed -18v not -8v ??

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if i cant mod it ..........NOBODY CAN

ok ignore that last post.........after some looking around i found another shop that sells dc-dc converters made by Meanwell no idea about them tho here is the data sheet (not much info) http://www.computronics.com.au/meanwell/spr/specpdf.pdf i was wondering if one of these could be used for negative voltages ? here is the shops home page http://www.computronics.com.au/meanwell/sg/dc.shtml

thanks alot!!

byteme

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if i cant mod it ..........NOBODY CAN

I only saw models up to 15v in those and you need minimum -18v.

But if these are suitable for negative voltages I'm not 100% sure. Datasheet mentions pins for -Vout and +Vout but also for -Vin and +Vin.

I've seen similar modules which documentation has clearly indicated that they can be used for negative voltages though.

huh?? there was 1 converter that did up to +-24 volts http://www.computronics.com.au/meanwell/dke10/ that could be used but it is VERY EXPENSIVE costing $27.75 australian or about $20 Usd!!! but i would use that if it means no extra wiring or anything on the side........honestly i'd rather pay for simplicity than scrooge on complexity (which probbably means i'd screw it up:P)

ByTeMe

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if i cant mod it ..........NOBODY CAN

I missed the DKE10 models when I checked the links last time. They should work fine with your display.
I don't think $20 is that bad for a converter that allows you to forget about building the MC34063 circuit. You can save a lot of time.