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    Blue HD44780 16x2 LCD with 3.3V ?

    Guys,

    Can I use blue HD44780 16x2 LCD with 3.3V power supply ?

    Thanks

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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    What does the specific data sheet say about the maximum voltage it can take?
    I ask because the HD44780 chip is often embedded in various manufacturers LCDs with their own part numbers and characteristics.
    Susan
    (PS: The Hitachi data sheet that a quick Google search for the chip finds does say it has a wide power supply range - but what it actually receives depends on what is around it on the LCD board.)



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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    Well according to the Hitachi datasheet for the display it can handle 2.7 to 5.5V. So I would say 3.3V is fine.

    You should probably grab the datasheet in the link if you plan on using this display.



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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    Although the HD44780 may work at 3.3V the LCD will not, in fact if it is a 5V LCD it will be blank at only 4.5V.


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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    Quote Originally Posted by pjmelect View Post
    Although the HD44780 may work at 3.3
    V the LCD will not, in fact if it is a 5V LCD it will be blank at only 4.5V.
    Can I hack 5V LCD to 3.3V ? any suggestions ? thanks



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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    Data lines can be connected directly, but supply voltage have to be 5V.
    Love me or hate me. All infractions will be ignored.



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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    Please see the link
    Perhaps this specific display could work with 3V3.

    https://www.sparkfun.com/products/9053



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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    Guys - some of you still seem to think that talking about the HD44780 chip that drives the actual display part of the LCD device is the same as the complete LCD device itself. It is NOT.
    Until the OP tells us the actual LCD he is using (make, part number, link to data sheet etc.) then we simply cannot tell whether it will work at 3V3 or not.
    Susan


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    Re: Blue HD44780 16x2 LCD with 3.3V ?




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    Re: Blue HD44780 16x2 LCD with 3.3V ?

    OK - doing a Google search on the QC1602A (as printed on the back of the display PCB) led to http://www.microelectronicos.com/datasheets/QC1602A.pdf which shows clearly that the voltage is 5V, as is the LED backlight supply.
    So this question really had nothing to do with the HD44780 chip itself and everything to do with the board it was used on. You don't directly supply the voltage to the HD44780 chip but to the board and there are uses for the voltage supply on the board other than the chip itself.
    Susan



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