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Author Topic: 6 volts ok for this LCD?  (Read 672 times)
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I am going to be prototyping something on a breadboard with a HD44780 type LCD (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=310232911382&ssPageName=STRK:MEWNX:IT) and was wondering if a 6v source would be ok, or should I stick much closer to 5? My plan is to use 4 AA batteries (1.5v each, 6v total) to power the breadboard.

Also, as I bought the LCD on ebay and it didn't come with a data sheet or anything, does anyone know what the pin-out for those pins is likely to be?

Thank you
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Here's the pinout (it was on the auction listing):

http://www.sure-electronics.net/mcu,display/DE-LM005-4.jpg

I would try to stick closer to 5V.  Do you have some diodes?  Stick 1-2 in series between the batteries and the LCD.  Your normal 1n4001 diode has ~0.7V drop.
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Ok, I figured that was the case. Do you think using one diode (would you recommend an LED?) would suffice?
« Last Edit: August 23, 2010, 12:17:55 pm by Major25 » Logged

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Quote
Ok, I figured that was the case. Do you think using one diode (would you recommend an LED?) would suffice?


Most LEDs drop 1.5 or more depending on their color type. A single silicon diode should be OK (say a 1N4001). From a HD44780 data sheet:

"The low power supply (2.7V to 5.5V) of the HD44780U is suitable for any portable battery-driven product
requiring low power dissipation."

http://pdf1.alldatasheet.com/datasheet-pdf/view/63673/HITACHI/HD44780.html

Lefty

« Last Edit: August 23, 2010, 01:14:27 pm by retrolefty » Logged

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Thank you so much for the information, it is perfect. I'll try ordering some of those diodes on ebay or something.
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Do these look like they'd do the job? I just want to make sure before I purchase :]

http://cgi.ebay.com/12pcs-1N4004-rectifier-diodes-1amp-upgrade-1n4001-/330413495176?pt=LH_DefaultDomain_0
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Those are the exact diodes that were recommended.  You can also pick them up at RadioShack.
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Yeah 1n4001 and 1n4004 are essentially the same (different reverse voltage tolerances I believe).  Both will work fine.  They're also very useful for other stuff such as motors and other coil-driven devices.
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