How to scale to 150 volts for LCD

[CocaColaKid]

Would it not make more sense to use a 1M and a 33K trimmer? This would allow you to achieve the optimum ration of 30:1 (150V/5V) would it not. With a 100K and 2.2K trimmer you'll have a ratio of 45:1 which will output only 3.33V at the full 150V.

[wildbilly]

Yes. Sounds and looks logical. Thanks for your input

[sayzer]

Would it not make more sense to use a 1M and a 33K trimmer? This would allow you to achieve the optimum ration of 30:1 (150V/5V) would it not. With a 100K and 2.2K trimmer you'll have a ratio of 45:1 which will output only 3.33V at the full 150V.

It was an example.

But, %1 of 1M is 100K.

That means, the resistor says 1M but it may actually be somewhere between 900K and 1100K.

That also means a lot more you know.
Using 33K trimpot is not going to be helpful in fixing the tolerance deviance.



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