Hello everyone, I have managed to set up the right contrast with my 25kOhm potentiometer for my 16x2 LCD. How do I replace it with a normal resistor? The resistance between the left and center pin is 21,8kOhms and the between the center and right pin 0 ohms. (I get the good contrast when the pot…

Grumpy_Mike: Does the voltage of that pin change depending on the power supply? Yes. If you look at the data sheet the output voltage of a pin is quoted as a fraction of the supply voltage. Good that I know that, because I'm going to use an external 6v power supply soon.

You better not because 6 V is too much for the chip.

Ok, so if I connect only 3 battery's in my battery pack, then I have 4,5v(3x1,5v). Will that be enough voltage to let the Arduino operate good?

Yes you should be OK with 4.5V.

You can also add a IN4001 diode in series with the supply to drop approximately .7 of a volt... The diode also protects your circuit should you accidentally reverse the supply :wink: Add a second diode to drop another .7 of a volt... Mike

I just used a 1k resistor from pin 3 to ground

If you're eliminating a big knob potentiometer, maybe you didn't realize there are smaller ones available? You should also consider an I2C backpack to save you pins and has a tiny onboard contrast pot.

Replace potentiometer with resistor for LCD contrast

Other Hardware Displays

kalmanroli January 12, 2019, 1:02pm 27

You'll need 1,330 ohm resistor from ground to V0 to make the screen look good.

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Replace potentiometer with resistor for LCD contrast

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