Diodes Incorporated – Magnetic switch ideal for contactless detection of case opening


The AH337 from Diodes Inc., is a Hall-effect switch which provides contactless detection of cover opening, enabling the designer to implement reliable tamper detection in a point-of-sale terminal.

The device includes an on-chip Hall voltage generator for magnetic sensing, an amplifier which amplifies the Hall voltage, a Schmitt trigger to provide switching hysteresis for noise rejection, and an open-collector output.

In the presence of a magnetic flux density higher than the operating- point threshold, the output is turned on. The output state is maintained until the magnetic flux falls below the release-point threshold.

• 2mA average supply current
• Operating-voltage range: 4.2V to 28V
• Open drain pre-driver