Honeywell SS343RT Unipolar Hall Effect Magnetic Sensor, 45 G to 205 G, SOT-23-3 Package

A unipolar sensor, like the SS343RT, activates its output only when a specific magnetic pole (typically the south pole) approaches and exceeds a threshold strength. It turns off when the field weakens below a release point. A bipolar sensor responds to both north and south poles, often used for direction sensing. The SS343RT is ideal for simple on/off proximity or position detection.

Connect the sensor's VCC pin to a 3V to 5V supply (within its 3-24V range), GND to ground, and the open-collector OUTPUT pin to a digital input pin on the Arduino via a pull-up resistor (typically 1kΩ to 10kΩ to VCC). The pin will be pulled low when a sufficient south magnetic field is detected and high when the field is removed.

The Operating Point (Bop) is the minimum magnetic field strength (45 to 205 Gauss) required to turn the sensor's output ON (pull low). The Release Point (Brp) is the field strength (40 to 180 Gauss) at which the output turns OFF (goes high) as the magnet moves away. The difference between these points provides hysteresis, preventing output chatter in noisy magnetic environments.

Yes. The Honeywell SS343RT is explicitly rated for an operating supply voltage range of 3V to 24V DC. You can connect it directly to a 24V rail common in PLC and industrial control systems without any additional voltage regulation, simplifying system design.