US3881

Hall Latch

Low Voltage & High Sensitivity

3901003881

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Data Sheet

Rev 014

Feb/06

9 Detailed General Description

Based on mixed signal CMOS technology, Melexis US3881 is a Hall-effect device with high magnetic

sensitivity. This multi-purpose latch suits most of the application requirements.

The chopper-stabilized amplifier uses switched capacitor techniques to suppress the offset generally

observed with Hall sensors and amplifiers. The CMOS technology makes this advanced technique possible

and contributes to smaller chip size and lower current consumption than bipolar technology. The small chip

size is also an important factor to minimize the effect of physical stress.

This combination results in more stable magnetic characteristics and enables faster and more precise design.

The operating voltage from 2.2V to 18V, low current consumption and large choice of operating temperature

range according to “L”, “K” and “E” specification make this device suitable for automotive, industrial and

consumer low voltage applications.

The output signal is open-drain type. Such output allows simple connectivity with TTL or CMOS logic by using

a pull-up resistor tied between a pull-up voltage and the device output.

10 Unique Features

The US3881 exhibits latch magnetic switching characteristics. Therefore, it requires both south and north

poles to operate properly.

SE package - Latch characteristic

UA package - Latch characteristic

means magnetic fields with equivalent strength and opposite direction drive the output high and low.

Removing the magnetic field (B→0) keeps the output in its previous state. This latching property defines the

device as a magnetic memory.

output oscillation near the switching point.