Hall-effect latch IC uses vertical Hall technology

June 24, 2015 // By Graham Prophet
The A1260 vertical Hall-effect sensor IC from Allegro MicroSystems Europe is a temperature-stable and stress-resistant magnetic sensing device for use in harsh operating environments, offering design flexibility with highly sensitive switch thresholds.

The device is actuated by alternating north and south polarity magnetic fields in parallel with the device's branded face rather than perpendicular to it as in a traditional Hall-effect sensor. This enables system designers to achieve new mechanical configurations not feasible with traditional planar Hall sensors, including replacing through-hole SIP devices with miniature surface-mount SOT23 ICs, saving space and cost.

The A1260 is optimised for the speed and position sensing of ring magnets in conjunction with motors or encoders or other moving or rotating assemblies, and is targeted at the automotive, communications, consumer and industrial markets. Key end applications include motor commutation and speed and direction sensing in automotive window lifts, sunroofs and tail/lift gates, white goods, automated window blinds, garage door openers and sliding doors.

The A1260 includes, on a single chip, a voltage regulator, Hall-voltage generator, small-signal amplifier, chopper stabilisation, Schmitt trigger circuitry, and an NMOS output that can sink up to 25 mA. The on-board regulator permits operation with supply voltages from 3 to 24V and incorporates EMC robustness for protection against high-voltage transient events.

The A1260 is qualified to AEC-Q100 standards and includes Zener clamps, output short-circuit protection, and reverse-battery protection. Superior high-temperature performance is made possible through dynamic offset cancellation, which reduces the residual offset voltage normally caused by device overmoulding, temperature dependencies, and thermal stress.

The device is highly sensitive with a typical operating point (BOP) of 25 Gauss, and its magnetic operating characteristics are specified across the operating voltage and temperature ranges.

The A1260 is supplied in two package types: a modified SOT23W surface-mount package (type LH) that switches with magnetic fields oriented perpendicularly to the non-leaded edge of the package; or an ultra-mini SIP (type UA), equipped for through-hole mounting and lead forming, that switches when a magnetic field is presented to the top edge of the package, parallel with the branded face.

Allegro MicroSystems; www.allegromicro.com