Allegro MicroSystems recently announced a new vertical Hall-effect sensor IC, an extremely temperature-stable and stress-resistant magnetic sensing device ideal for harsh operating environments. Allegro's A1260 is actuated by alternating north and south polarity magnetic fields in plane with the device's branded face rather than perpendicular to the branded face, 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 tiny surface-mount SOT23 ICs.
The A1260 is optimized for the speed and position sensing of ring-magnets (motors/encoders) or other moving/rotating assemblies and is targeted at the automotive, communications, consumer and industrial markets. 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.
Each device includes on a single silicon chip a voltage regulator, a Hall-voltage generator, a small-signal amplifier, chopper stabilization, a Schmitt trigger, and NMOS output that can sink up to 25 mA. The on-board regulator permits operation with supply voltages of 3 V to 24 V and adds EMC robustness such as greater 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. High-temperature performance is made possible through dynamic offset cancelation, which reduces the residual offset voltage normally caused by device overmolding, temperature dependencies, and thermal stress.
The device is highly sensitive (BOP = 25 G typical) and its magnetic operating characteristics are specified across the operating voltage and temperature ranges. Package type LH is a modified SOT23W surface mount package that switches with magnetic fields oriented perpendicularly to the non-leaded edge of the package. The UA package is an ultra-mini SIP, 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. Both packages are RoHS-compliant and lead (Pb) free (suffix, -T), with 100% matte-tin plated leadframes.