49E Hall Effect Sensor (SS49E) Overview

The 49E Hall Effect Sensor, also known as SS49E, OH49E, or A3144-compatible, is a linear analog Hall effect sensor that delivers a voltage output proportional to the magnetic field strength it detects. This sensor is a popular choice for DIY electronics, robotics, and automotive projects, where it is used to detect magnetic fields and measure proximity, position, or current.

🔎 Key Features and Specifications

Type: Linear analog (not digital on/off)
Operating Voltage: 2.7V to 6.5V (typically 5V)
Output: Analog voltage (centered around Vcc/2)
Sensitivity: Typically around 1.3 to 2.5 mV/Gauss
Package: TO-92 or SOT-23
Current Consumption: Low (milliamps range)
Output Impedance: ~1 kΩ
 

🔌 Pinout (TO-92 Package)

1 - Vcc (2.7V–6.5V)2 - GND3 - Vout (Analog Voltage)Note: Always refer to the datasheet for the exact pin configuration.

📚 Working Principle

The 49E Hall Effect Sensor operates on the principle that when no magnetic field is present, the output voltage is approximately Vcc / 2. The presence of a north pole near the sensor decreases the voltage, while a south pole increases it. The output voltage varies linearly with the strength and polarity of the magnetic field.

🛠️ Typical Applications

• Proximity detection
• Brushless DC motor commutation
• Current sensing
• Position or rotational speed sensing
• Magnetic encoders