Chopper Stabilized, Precision Hall-Effect Latches for Consumer and Industrial Applications

The A3290 and A3291 Hall-effect latches are extremely temperature-stable and stress-resistant sensor ICs, especially suited for operation over extended temperature ranges (up to 125°C). Superior high-temperature performance is made possible through Dynamic Offset Cancellation, which reduces the residual offset voltage normally caused by device package overmolding, temperature dependencies, and thermal stress. The two devices are identical except for their magnetic switchpoints. They are not intended for automotive applications.

Both devices include, on a single silicon chip, a voltage regulator, a Hall-voltage generator, a small-signal amplifier, chopper stabilization, a Schmitt trigger, and a short-circuit protected open-drain 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 3 to 24 volts.

Two package styles provide a magnetically optimized package for most applications. Type LH is a miniature SOT23W low-profile surface-mount package, and type UA is a three-pin ultramini SIP for through-hole mounting. Both packages are lead (Pb) free with 100% matte tin leadframe plating.