Production£º

¡¾Part No.¡¿  A3209 A3210
¡¾Category¡¿  MICROPOWER,ULTRA-SENSITIVE HALL-EFFECT SWITCHES
¡¾Packing¡¿   SOT23W
¡¾MFQ¡¿       ALLEGRO
¡¾Datasheet¡¿ A3209 A3210 Datasheet

Description

The A3209Ex and A3210Ex integrated circuits are ultra-sensitive, pole
independent Hall-effect switches with a latched digital output. They are
especially suited for operation in battery-operated, hand-held equipment such as
cellular and cordless telephones, pagers, and palmtop computers. 2.5 volt to
3.5 volt operation and a unique clocking scheme to reduce the average operating
power requirements ¨C the A3209Ex to 400 ¦ÌW, the A3210Ex to 25 ¦ÌW!
Except for operating duty cycle and average operating current, the A3209Ex
and A3210Ex are identical.
Unlike other Hall-effect switches, either a north or south pole of sufficient
strength will turn the output on; in the absence of a magnetic field, the output is
off. The polarity independence and minimal power requirement allows these
devices to easily replace reed switches for superior reliability and ease of
manufacturing, while eliminating the requirement for signal conditioning.
Improved stability is made possible through chopper stabilization (dynamic
offset cancellation), which reduces the residual offset voltage normally caused
by device overmolding, temperature dependencies, and thermal stress.
These devices include on a single silicon chip a Hall-voltage generator,
small-signal amplifier, chopper stabilization, a latch, and a MOSFET output.
Advanced BiCMOS processing is used to take advantage of low-voltage and
low-power requirements, component matching, very low input-offset errors,
and small component geometries.
The A3209Ex and A3210Ex are rated for operation over a temperature
range of -40¡ãC to +85¡ãC. Two package styles provide a magnetically optimized
package for most applications. Suffix ¡®LH¡¯ is a miniature low-profile
surface-mount package while suffix ¡®UA¡¯ is a three-lead ultra-mini-SIP for
through-hole or surface mounting.