Linear Hall sensor

By Admin, 15/09/2026 · 4 min read

Linear Hall sensor guide for the 37-in-1 Arduino Sensors Kit.

37-in-1 kit, module 22

KY-024: Linear Hall sensor

Magnet strength as a number, plus a threshold output. Plug it in, upload the sketch, then change the thing it senses and watch the reading.

All 37 modules Nano and shield wiring Joy-IT page for this module

KY-024, Linear Hall sensor

Magnet strength as a number, plus a threshold output.

How it works

Linear Hall sensor

What is going on

A Hall-effect sensor whose output voltage varies with field strength, not just on and off. The analog pin reads how strong and which way the field is; the digital pin flips when it crosses the level set by the blue potentiometer. Move a magnet closer and the number climbs; flip the magnet and it goes the other way from the midpoint.

Connections

Wiring to the Arduino Nano on its expansion shield

The pins below match the sketch further down this page; change one and change the other.

Power off first

Unplug the USB cable before you plug in, move or remove any module.

A lead plugged in live can touch the wrong pin for a moment, and 5 V on a signal pin is how a module dies. Unplug, wire, check the letters, then plug the cable back in.

Module pinGoes to

Module A0S row of the column marked A0, analog bank

Module D0S row of the column marked 3, digital bank

Module +VV row, 5 V

Module GNDG row, ground

Where it plugs in on the shield

The ringed column is the one this module uses. G on top for ground, V in the middle for 5 V, S at the bottom for the signal. A module with more than one signal wire uses one column per wire.

Read the letters on the shield

Both banks on this shield read G, V, S from the top. The letters are printed at the ends of the rows.

The module's minus or GND pin goes to G, its plus or VCC pin to V, and each signal to the S row of the numbered column.

A module in backwards puts 5 V on the signal pin. Some survive it, plenty do not.

Starter sketch

Code you can copy and upload

Every sketch on these pages is compiled for the Arduino Nano before it is published. The pin numbers at the top match the connection table above.

ky024.inoArduino C++

1const uint8_t FIELD = A0, THRESH = 3;
2
3void setup() {
4  pinMode(THRESH, INPUT);
5  Serial.begin(9600);
6}
7
8void loop() {
9  Serial.print("field:");
10  Serial.print(analogRead(FIELD));
11  Serial.print(",over:");
12  Serial.println(digitalRead(THRESH));
13  delay(100);
14}

Try first

Plot it, then bring a magnet in slowly and flip it over half way.

The quickest way to see it respond.

1

Unplug the USB cable. Plug the module into the column shown above, minus to G, plus to V, signal to S.

2

Plug the USB cable back in. Copy the sketch, upload it, and open Tools > Serial Monitor at 9600 baud.

3

Do the thing the module senses and watch the reading, the L LED, or the sound respond.

Reference

More on this module

The Joy-IT page has the datasheet figures and examples for other boards; the repository has the original vendor files.

Joy-IT SensorKit: KY-024
KY-numbered kit repository: datasheets and original examples
Arduino Nano and I/O expansion shield wiring
Arduino Nano and DHT11 electronics workshop
All 37 modules

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Linear Hall sensor

KY-024: Linear Hall sensor

KY-024, Linear Hall sensor

Linear Hall sensor

What is going on

Wiring to the Arduino Nano on its expansion shield

Where it plugs in on the shield

Read the letters on the shield

Code you can copy and upload

Plot it, then bring a magnet in slowly and flip it over half way.

More on this module

Help improve MakerAccess

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