Hall Effect Magnetic Sensor Module KY-035

Features:

• Analog output (unlike KY-003 which provides digital output)
• Compatible with Arduino, Raspberry Pi, and ESP32
• Miniature construction
• Low power consumption: 3.5mA at 5V
• Linear and low-noise output
• Stable and accurate over a wide temperature range (-40°C to 85°C)
• Responds to both positive and negative Gauss
• Reverse voltage protection included

Specifications:

• Model: KY-035
• Sensor IC: AH49E
• Supply Voltage: 5V
• Output Type: Analog
• Output Current: 10 mA
• Operating Temperature Range: -40°C to 125°C

Principle of Work:

As magnetic induction increases, the output voltage of the sensor changes linearly until saturation. When the north (N) pole of a magnet approaches the sensor’s marked surface (B-), the output voltage decreases. When the south (S) pole approaches (B+), the output voltage increases. This behavior is symmetrical and ideal for applications that require detection of polarity and intensity.

Pinout:

• GND – Connect to MCU Ground
• VCC – Connect to +5V of MCU
• S (Signal) – Connect to analog input pin of MCU

Applications:

• Brushless DC motors: Detect position of permanent magnets
• Printers: Detect missing paper or open covers
• General-purpose magnetic switches

Circuit Diagram:

Connect the signal output (S) to Arduino analog pin A0. Connect VCC to 5V and GND to ground.

Sample Code:

int led = 13;        // LED pin
int sensor = A0;     // Sensor analog pin
int val;             // Variable to store sensor value

void setup() {
  pinMode(led, OUTPUT);  // Set LED pin as output
}

void loop() {
  val = analogRead(sensor);  // Read analog value from sensor
  if (val > 400) {           // Threshold for magnetic field detection
    digitalWrite(led, HIGH); // Turn on LED
  } else {
    digitalWrite(led, LOW);  // Turn off LED
  }
}

Resources:

• Tutorial
• Datasheet

Comparison with KY-003:

• KY-035 uses AH49E and provides an analog output
• KY-003 uses 3144EUA-S and provides a digital output
• KY-003 operates from 4.5V–24V (not suitable for ESP32/RPi)
• KY-035 operates from 3V–5V (compatible with ESP32 and RPi)