US1881 Hall Effect Sensor (Latching) - (AD22971)

Description:

The US1881 is an integrated Hall-effect latching sensor. That's nice, but what does it do? Holding a magnet near the sensor will cause the output pin to toggle. This makes it a robust presence sensor. A reed sensor also works well, but may be limited by the encapsulation and size of the glass. A Hall-effect sensor is much smaller, but can handle less current than a reed switch.

The device includes an on-chip Hall voltage generator for magnetic sensing, a comparator that amplifies the Hall voltage, and a Schmitt trigger to provide switching hysteresis for noise rejection and open-collector output. An internal bandgap regulator is used to provide temperature-compensated supply voltage for internal circuitry and enables a wide operating supply range.

If the magnetic flux density is greater than the threshold Bop, DO turns on (low). The output state is maintained until a magnetic flux density reversal falls below Brp, causing DO to turn off (high).

Characteristics:

- Operating voltage from 3.5V to 24VDC

- Low current consumption

- Temperature compensation

- Wide operating voltage range

- Open collector precontroller

- Maximum output current of 50 mA

- Reverse polarity protection

Documents:

• Datasheet
• Bildr Tutorial

Reference link