Each device includes, on a single silicon chip, a voltage regulator, a Hall-voltage transducer, a small-signal amplifier, chopper stabilisation circuitry, a Schmitt trigger, and a short-circuit protected open-collector output to sink up to 25 mA.
A south polarity magnetic field of sufficient strength is required to turn the output on. A north polarity field of sufficient strength is necessary to turn the output off. An onboard regulator permits operation with supply voltages in the range of 4.2 to 24 V with an operating temperature range of -40°C to +125°C.
The combination of resistance to physical stress, temperature stability, output short-circuit protection, ability to operate from unregulated supplies, reverse battery protection and solid-state reliability mean that these devices are especially suited for replacing electromechanical switches in consumer and industrial products.
The A3290 and A3291 are available in a three-lead single in-line package (UA) and a SOT-23W surface mount package (LH).