The UR4120 is a Hall effect latch manufactured by Fairchild/ON Semiconductor. This sensor detects the presence and polarity of a magnetic field. When a magnetic field of sufficient strength is applied, the UR4120's output switches to a specific state and latches in that state, maintaining the output until a magnetic field of opposite polarity is applied to reset it. This latching behavior makes it suitable for applications requiring reliable state detection.

Applications

• Brushless DC (BLDC) motor control: Providing rotor position feedback for efficient motor commutation.
• Proximity sensing: Detecting the presence or absence of objects.
• Position detection: Determining the location of a moving part.
• Flow measurement: Detecting the rotation of a flow meter impeller.
• Revolution counting: Counting the number of rotations of a shaft or wheel.

Features

• Hall effect technology: Provides contactless sensing of magnetic fields.
• Latching operation: Output remains in a set state until reset by an opposite magnetic field.
• High sensitivity: Detects relatively weak magnetic fields.
• Wide operating voltage range: Can operate over a broad range of supply voltages.
• Small package size: Enables compact designs.

Benefits

• Reliable sensing: Provides accurate and repeatable detection of magnetic fields.
• Long operating life: Contactless sensing eliminates mechanical wear.
• Immunity to environmental factors: Resistant to dust, dirt, and moisture.
• Versatile applications: Suitable for a wide range of sensing and control applications.

Additional Details

The UR4120 typically comes in a small surface-mount package, such as SOT-23 or similar. The specific operating voltage range, sensitivity, and switching characteristics vary depending on the manufacturer's specifications. The datasheet provides comprehensive details on electrical characteristics, magnetic field thresholds, and temperature performance. Proper decoupling capacitors are generally recommended for stable operation. It requires an external pull-up resistor. Refer to the datasheet for more specific requirements for this part.