The A3213 and A3214 integrated circuits are ultra-sensitive, pole independent Hall-effect switches with a latched digital output. They are especially suited for operation in battery-operated, hand-held equipment such as cellular and cordless telephones, pagers, and palmtop computers. A 2.4 to 5.5 V operation and a unique clocking scheme reduce the average operating power requirements the A3213 to 825 µW, the A3214 to 14 µW (typical, at 2.75 V). Except for operating duty cycle and average operating current, the A3213 and A3214 are identical.
Unlike other Hall-effect switches, either a north or south pole of sufficient strength will turn the output on; in the absence of a magnetic field, the output is off. The polarity independence and minimal power requirement allows these devices to easily replace reed switches for superior reliability and ease of manufacturing, while eliminating the requirement for signal conditioning.