Not to scale
Description
The A3213 and A3214 integrated circuits are ultra-sensitive,
pole in de pen dent Hall-effect switches with a latched digital
output. They are es pe cial ly suited for operation in battery-
operated, hand-held equip ment such as cell and cordless
tele phones and palmtop com put ers. A 2.4 to 5.5 V operation
and a unique clocking scheme reduce the average op er at ing
power requirements: the A3213 to 825 μW, the A3214 to 14 μW
(typical, at 2.75 V). Except for operating duty cycle and average
operating current, the A3213 and A3214 are identical.
Unlike other Hall-effect switches, either a north or south pole
of suf fi cient 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 (dy nam ic offset cancellation), which reduces the
residual offset voltage normally caused by device overmolding,
temperature de pen den cies, and thermal stress.
These devices include, on a single silicon chip, a Hall-voltage
27622.62-DS Rev. Y
Features and Benefits
▪ Micropower operation
▪ Operate with north or south pole
▪ 2.4 to 5.5 V battery operation
▪ Chopper stabilized
▫ Superior temperature stability
▫ Extremely low switchpoint drift
▫ Insensitive to physical stress
▪ High ESD protection
▪ Sol id state reliability
▪ Small size
▪ Easily assembly into applications due to magnetic pole
independence
Micropower Ultra-Sensitive Hall-Effect Switches
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Packages
Functional Block Diagram
A3213 and A3214
3 pin surface mount
SOT23-W (suffix LH)
3 lead ultramini SIP
(suffix UA)
TIMING
LOGIC
Dwg. FH-020-5
LATCH
GROUND
OUTPUT
SUPPLY
X
DYNAMIC
OFFSET CANCELLATION
SWITCH
SAMPLE
& HOLD
