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series resistors on lcd data lines

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yougarage

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Hi!
I'm designing a simple pcb to interface a microcontroller to a parallel graphic lcd.(HD44780 standard)
I'm wondering if I would need to put series resistors between the data lines and the microcontroller.
I tested it without them, it works fine, but I'd like to improve reliability and noise immunity.
Do you think this solution could improve my design?
 

No - I've never seen that done and see no benefit. If anything, I would think that it could reduce reliability and increase noise susceptibility.
 

If you are having immunity issues, ensure that
"When the liquid crystal display panel has unused extra scanning lines, connect the extra scanning lines to these common signal pins to avoid any undesirable effects due to crosstalk during the floating state." and never exceed absolute maximum ratings on any pin.
 

yougarage said:
I'm wondering if I would need to put series resistors between the data lines and the microcontroller.
I tested it without them, it works fine, but I'd like to improve reliability and noise immunity.
Do you think this solution could improve my design?
Click to expand...

No, it will not improve the design.

However, if you are using a 4-bit interface instead of the 8-bit interface ensure you tie the unused data lines to ground.

BigDog
 

Thanks for your advices
I'm using all the 8 bit data lines so I won't have unused pins.
 

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