KY-003 Magnetic Hall Sensor (Digital Switch)


The KY-003 is a magnetic switch. If no magnetic field is present, the signal line of the sensor is HIGH (3.5 V). If a magnetic field is presented to the sensor, the signal line goes LOW, at the same time the LED on the sensor lights up. The polarity of the magnetic field is of influence to the switching action. The front side of the sensor needs the opposite polarity as the back of the sensor to switch on.

Out of stock


Using KY-003 Magnetic Hall Sensor in the example program the led on the Arduino (pin 13) will be turned on when a magnetic field is present.

KY-003 Magnetic Hall Sensor Connecting

  • Pin – = GND, connect to GND of the Arduino
  • Pin (middle pin) +5 v, connect to Arduino +5
  • Pin S signal, connect to Arduino pin 10
  • Power consumption, 3 mA in rest, 8 mA when switched on


/*KY-003 Hall magnetic switch*/
 int Led = 13 ; // define LED Interface
 int SENSOR = 10 ; // define the Hall magnetic sensor interface
 int val ; // define numeric variables val
 void setup (){
  pinMode (Led, OUTPUT) ;    // define LED as output interface
  pinMode (SENSOR, INPUT) ;  // define the Hall magnetic sensor line as input
 void loop (){
  val = digitalRead (SENSOR) ; // read sensor line
  if (val == LOW) // when the Hall sensor detects magnetic field, Arduino LED is up
    digitalWrite (Led, HIGH);
  } else {
    digitalWrite (Led, LOW);

Additional information

Weight5 g


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.