The A3213xx and A3214xx 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. A 2.4 volt

to 5.5 volt operation and a unique clocking scheme reduce the average oper-

ating power requirements – the A3213xx to 825 µW, the A3214xx to 14 µW

(typical at 2.75 V)! Except for operating duty cycle and average operating

current, the A3213xx and A3214xx 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 (dy-

namic 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.

Range 'E' devices are rated for operation over a temperature range of

-40°C to +85°C; range 'L' devices are rated for operation over a temperature

range of -40°C to +150°C. Two package styles provide a magnetically opti-

mized package for most applications. ‘LH’ is a miniature low-profile surface-

mount package, ‘UA’ is a three-lead SIP for through-hole mounting. Each

package is available in a lead (Pb) free version (suffix, –T) , with a 100% matte

tin plated leadframe.

FEATURES

■ Micropower Operation

■ Operate With North or South Pole

■ 2.4 V to 5.5 V Battery Operation

■ Chopper Stabilized

Superior Temperature Stability

Extremely Low Switch-Point Drift

Insensitive to Physical Stress

■ ESD Protected to 5 kV

■ Solid-State Reliability

■ Small Size

■ Easily Manufacturable With Magnet Pole Independence

Package Designator ‘LH’ Pinning

(SOT23W)

3214

ABSOLUTE MAXIMUM RATINGS

Magnetic Flux Density, B .......... Unlimited

Suffix 'E' ...................... -40°C to +85°C

Suffix 'L' ................... -40°C to +150°C

Storage Temperature Range,

Caution: These CMOS devices have input

static protection (Class 3) but are still sus-

ceptible to damage if exposed to extremely

high static electrical charges.

Pinning is shown viewed from branded side.

MICROPOWER, ULTRA-SENSITIVE

HALL-EFFECT SWITCHES

Dwg. PH-016-1

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