Linear Hall Effect Sensor ICs with Analog Output

A1324, A1325,

and A1326

6

Allegro MicroSystems, LLC

115 Northeast Cutoff

Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

back to up 25°C.

Linearity Sensitivity Error The 132x is designed to provide

linear output in response to a ramping applied magnetic field.

Consider two magnetic fields, B1 and B2. Ideally the sensitivity

of a device is the same for both fields for a given supply voltage

and temperature. Linearity sensitivity error is present when there

is a difference between the sensitivities measured at B1 and B2.

Linearity Sensitivity Error is calculated separately for the positive

earity Sensitivity Error (%) is measured and defined as:

1–













1–













(7)

and

(8)

where:













(9)

and B(++), B(+), B(––), and B(–) are positive and negative mag-

netic fields with respect to the quiescent voltage output such that

|B(++)| > |B(+)| and |B(––)| > |B(–)| .

Symmetry Sensitivity Error The magnetic sensitivity of a

device is constant for any two applied magnetic fields of equal

magnitude and opposite polarities.

Symmetry Error (%), is measured and defined as:

1–













(11)

tive and negative magnetic fields such that |B(+)| = |B(–)|.

Ratiometry Error The A132x features a ratiometric output.

the supply voltage increases or decreases by a certain percent-

age, each characteristic also increases or decreases by the same

percentage. Error is the difference between the measured change

in the supply voltage, relative to 5 V, and the measured change in

each characteristic.

1–













(12)

1–













(13)