(100K+56K)/56K = 3.78
This has a measurable voltage range of 0-18.9 volts, this take care of the potential voltage spike when the battery is on charge or at ignition.
The 22uF capacitor is to reduce the spike measured by Arduino.
#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
const int sensorPin = A0;
const float DivderRatio = 3.78;
void setup(){
Serial.begin(9600);
lcd.begin(16,2);
lcd.print("KTM 690 ENDURO");
lcd.setCursor(0,1);
lcd.print("Volt =");
}
void loop() {
int sensorValue = analogRead(sensorPin);
float sensorVoltage = (sensorValue/1024.0) * 5.0;
float vcc = sensorVoltage * DivderRatio;
Serial.print("Sensor Value=");
Serial.print(sensorValue);
Serial.print("\t volt=");
Serial.print(sensorVoltage);
Serial.println("\t Vcc=");
Serial.println(vcc);
lcd.setCursor(11,1);
lcd.print(vcc);
delay(150);
}
