Omnipolar 3D magnetic sensor IC using vertical Hall-effect technology

Highly sensitive IC detects magnetic proximity and tampering

The new A1266 from Allegro MicroSystems Europe is a unique 3-dimensional sensor IC incorporating a combination of vertical and traditional planar Hall-effect sensor ICs that can detect a magnetic field of either polarity in any direction.

The omnipolar, omnidirectional sensitivity of the new device makes it ideal for detecting magnetic tampering in smart meters, ATMs, gambling/gaming machines, ticket machines and electronic locks. The A1266 can also serve as a general-purpose magnetic switch that is virtually insensitive to magnet orientation or polarity in applications such as games, consumer electronics and white goods.

This compact surface-mount SOT23 IC is functionally equivalent to an array of three standard Hall-effect sensors mounted in three different orientations: something that is not possible using a single circuit board and all surface-mount components. With a typical BOP operating point of 25 G, the A1266 has higher sensitivity than most conventional Hall-effect switches, leading to high-sensitivity 3D tamper or proximity sensing in less space with lower assembly cost.

Each device integrates, on a single silicon chip, three Hall-voltage generators, a small-signal amplifier, chopper stabilisation, a Schmitt trigger, and one or more NMOS outputs. Allegro’s proprietary dynamic offset cancellation technique means that the magnetic operating characteristics are specified across the operating voltage and temperature ranges.

The A1266 is designed for operation in green and battery-powered systems; it can be powered from a 2.5 - 5.0 V supply and the average supply current is typically 7.5 µA at 2.5V. The operating temperature range is -40̊ to +85°C.

Two configurations are available: one with a separate output for each sensing direction (X, Y, Z) and one with a combined output (X+Y+Z). Package type LH is a modified SOT23W surface-mount package that is RoHS-compliant and lead (Pb) free (suffix -T), with a 100% matt-tin plated leadframe.

About Allegro

Allegro MicroSystems, LLC is a leader in developing, manufacturing and marketing high-performance semiconductors. Allegro's innovative solutions serve high-growth applications within the automotive market, with additional focus on office automation, industrial, and consumer/communications solutions. Allegro is headquartered in Worcester, Massachusetts (USA) with design, applications, and sales support centers located worldwide. Further information about Allegro can be found at www.allegromicro.com

Allegro MicroSystems Europe, headquartered in Chertsey, United Kingdom, is the European sales and marketing operation, and operates a network of representatives and distributors throughout Europe.  Allegro also has an engineering design centre in Edinburgh in Scotland and an application and marketing centre in Annecy in France.