US1881 Datasheet, PDF (5/12 Pages) List of Unclassifed Manufacturers – CMOS MULTI-PURPOSE LATCH

US1881
Hall Latch – High Sensitivity
9 Detailed General Description
Based on mixed signal CMOS technology, Melexis US1881 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 technique 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 wide operating voltage from 3.5V to 24V, 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 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 US1881 exhibits latch magnetic switching characteristics. Therefore, it requires both south and north
poles to operate properly.
SE package - Latch characteristic
UA package - Latch characteristic
The device behaves as a latch with symmetric operating and release switching points (B_OP=|B_RP|). This
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.
A magnetic hysteresis B_HYST keeps B_OP and B_RP separated by a minimal value. This hysteresis prevents
output oscillation near the switching point.
3901001881
Rev 015
Page 5 of 12
Data Sheet
Jan/06