LED 12C not working

Other Hardware Displays
7

First off, you can just experiment with dtrostre()

void setup()
{
    Serial.begin(9600);
    char buf[20];
    for (float Voltage = 0.0; Voltage < 12; Voltage++) {
        float pressure = pow(10, 1.66 * Voltage - 11.46);
        dtostre(pressure, buf, 3, 0);
        Serial.print("Voltage = ");
        Serial.print(Voltage, 3);
        Serial.print(" Pressure = ");
        Serial.println(buf);
    }
}

void loop()
{
}

and get:

Voltage = 0.000 Pressure = 3.467e-12
Voltage = 1.000 Pressure = 1.585e-10
Voltage = 2.000 Pressure = 7.244e-09
Voltage = 3.000 Pressure = 3.311e-07
Voltage = 4.000 Pressure = 1.514e-05
Voltage = 5.000 Pressure = 6.918e-04
Voltage = 6.000 Pressure = 3.162e-02
Voltage = 7.000 Pressure = 1.445e+00
Voltage = 8.000 Pressure = 6.607e+01
Voltage = 9.000 Pressure = 3.020e+03
Voltage = 10.000 Pressure = 1.380e+05
Voltage = 11.000 Pressure = 6.310e+06

So it looks as if 760 Torr will be displayed when the Voltage is about 8.63V

Read the docs to see how to change the precision. Read the docs to see how to read 0-5V with analogRead()

David.