The A3211 and A3212 integrated circuits are ultra sensitive, highly independent Hall effect switches with latched digital outputs. These devices are ideal for operating in battery powered handheld devices such as cellular and cordless phones, pagers, and handheld computers. 2.5~3.5 V working voltage and unique clock scheme reduce the average working power requirement under 2.75 V power supply to 15 μ W below.
Functional Block Diagram
Different from other Hall effect switches, as long as there is sufficient strength of the North or South Pole, the output of the A3212 will be turned on, and in the absence of a magnetic field, the output will be turned off. The A3211 provides inverted output. Polarity independence and minimum power requirements enable these devices to easily replace reed switches, resulting in higher reliability and ease of manufacture, while eliminating the need for signal conditioning. By chopping stabilization (dynamic offset cancellation), the residual offset voltage usually caused by device overmode, temperature dependence and thermal stress is reduced, and the stability is improved.
The device includes Hall voltage generator, small signal amplifier, chopper stabilization, latch, and MOSFET output on a single silicon chip. Adopt advanced CMOS technology and take advantage of low voltage and low power consumption