High Precision Linear Hall-Effect Device for High-Temperature Operation

Allegro Microsystems announces the development of a new linear Hall-effect sensor IC, the A3516, that utilizes a revolutionary chopper stabilization technique for offset reduction. The A3516 provides precise measurements of the incident magnetic field while being impervious to ambient temperature and package stress. This design breakthrough allows for a significant improvement in offset drift over existing linear Hall devices.

The A3516 is a monolithic integrated circuit which incorporates a single Hall element, a high gain amplifier, a voltage regulator, and offset cancellation circuitry that includes an oscillator, chopper stabilization circuitry, and differential filter capacitors. The rail-to-rail output is also ratiometric with supply voltage.

A unique approach is used to cancel chip offsets which are the source of output drift with temperature and stress. A switching circuit changes the energizing polarity of a single Hall element and a differential amplifier, and averages out the resulting Hall and amplifier offset while amplifying the magnetic induced signal. A 10x reduction in offset is achieved over conventional techniques. In addition, internal temperature compensation circuitry lowers the intrinsic drift of the Hall element, allowing it to operate reliably and continuously to +15O°C.

This combination of extremely low quiescent voltage drift and high sensitivity makes this temperature stable device ideally suited to linear and rotary position sensing applications in automotive or harsh industrial applications. The device will operate from 4.5 to 6 V and is supplied in a single inline UA style package.

About Allegro

Allegro MicroSystems, Inc. is a leader in developing, manufacturing and marketing high-performance power and Hall-effect sensor integrated circuits. Allegro's innovative solutions serve high-growth applications within the automotive, communications, computer/office automation, consumer and industrial markets. Allegro is headquartered in Worcester, Massachusetts (USA) with design and applications centers located in North and South America, Asia, and Europe. Further information about Allegro can be found at www.allegromicro.com.

Editorial Contact:
Stephanie Fennelly
Director - Marketing Communications
Tel: (508) 854-5363
sfennelly@allegromicro.com