int pinoPot = A0;
int led = 3;
int valorPot = 0;
int pwm = 0;

void setup() {
  pinMode(led, OUTPUT);
}

void loop() {
  valorPot = analogRead(pinoPot);
  pwm = map(valorPot, 0, 1023, 0, 255);
  analogWrite(led, pwm);
}