General Description

Using low power CMOS process, the AS1891 is
designed for low power, high performance omnipolar
detection hall-effect application, such as cover switch, contactless switch, solid state switch and lid close
sensor etc battery operation. The hall IC integrated an
on-chip hall voltage generator for magnetic sensing, a
comparator that amplifiers the hall voltage, a Chopper
amplifier, a Schmitt trigger to provide switching
hysteresis for noise rejection, and a complementary
output. The total power consumption of AS1891 is
typically less than 3.5mA at 3.6V power supply. AS1891 is designed to respond to alternating North
and South poles. When the magnetic flux density (B) is
larger than operate point (BOP), the output will be
turned on (low), the output is held until the magnetic
flux density (B) is lower than release point (BRP), then
turn off (high). The device is available in SOT23-3L and SIP-3L
Package and is rated over the -40°C to 125°C. The all
packages are RoHS and Green compliant.

Features

 Input Voltage Range : 2.2V to 5.5V
 Omniplar Operation, easy to use as output
 Very high sensitivity hall sensor
 Chopper stabilization amplifier stage
 Magnetic Sensitivity (typical)
BOP=±100Gauss, BRP=±80Gauss
 Good RF noise immunity
 Open Drain Output Capable of 20mA
 Small Solution Size
 RoHS & Green Compliant
 SOT23-3L and SIP-3L Packages
 -40℃ to +125 ℃ Temperature Range

Applications

 Speed and Rotational Speed Detection
 Contact-less switch in consumer products
 Solid State Switch
 Handheld Wireless Handset Awake Switch
 Lid close sensor for battery-powered devise
 Magnet proximity sensor for reed switch
replacement in low duty cycle applications