# How can we replace a 10k potentiometer with resistors?

I am using an LCD (16x2) with an Arduino Uno R3, in for that I need a 10 kΩ potentiometer, but I don't have it now. How can I replace that?

I have resistors of many kinds and a 1 kΩ potentiometer.

Just use your 1k pot in place of the 10k pot. The resistance doesn't matter that much (though you don't want to go loo low or you could draw too much current) since it is just being used as a voltage divider to set an offset point for the LCD.

• "though you don't want to go loo low" just to be sure: a 1k pot can go as low as a 10k pot, right? Like from 0 to 1k rather than from 0 to 10k, and the zero being the lowest value? Apr 3 '16 at 9:44
• No. Like using a 100 ohm potentiometer. It's the total pot resistance that determines the current drawn from Vee.
– Majenko
Apr 3 '16 at 9:46
• Ah, you wrote "voltage divider", so that connects all 3 pins of the pot of course. Thanks! Apr 3 '16 at 9:48
• I tried it but the brightness is too high so that the letters are not visible. Apr 3 '16 at 10:32

Derived from Ohm's Law:

• R = R1 + R2 + ... + Rn (For resistors in Series)
• (1/R) = (1/R1) + (1/R2) + ... + (1/Rn) (For resistors in Parallel)

You can use any resistance from 1k to 10k with your LCD but the actual value depends on your choice and preferences. You may start with 5k and if you have one then its allright. But if you do not have a resistor of that value you can join resistors of lower values in series with your 1k POT to get resistance of 5k ~ 6k.

In such a way you may get a variable resistance (1k pot) with a suitably high value (other resistors in series). If you wish, you may add more resistors to get higher values like 8k ~ 9k and so on.

Try using 9k~1k. (It worked for my 16*2 LCD)

Or place 9k in series with 1K and vary that.

Connect 10 of your 1K resistors in series. Connect one end to GND and other end to VCC. Now, you will have 10 different nodes (including VCC and GND) each having a different voltage. Connect your desired input pin to any of those nodes.

• can you please decribe the circuit(resistors)? Apr 3 '16 at 7:13
• Ok. Connect 10 of your 1K resistors in series. Connect one end to GND and other end to VCC. Now, you will have 10 different nodes (including VCC and GND) each having diff. voltage. connect you desired input pin to any of that node.
– ARK
Apr 3 '16 at 7:17
• copt-ied past-ed same sentence? :)
– ARK
Apr 3 '16 at 7:29