ALLEGRO A 1326 LUA-T Datasheet

A1324, A1325, and A1326

Low Noise, Linear Hall Effect Sensor ICs with Analog Output

Features and Benefits

• Temperature-stable quiescent output voltage and sensitivity

• Output voltage proportional to magnetic flux density

• Low-noise output increases accuracy

• Precise recoverability after temperature cycling

• Ratiometric rail-to-rail output

• Wide ambient temperature range: –40°C to 150°C

• Immune to mechanical stress

• Solid-state reliability

• Enhanced EMC performance for stringent automotive
applications

Packages

3-pin ultramini SIP

1.5 mm × 4 mm × 3 mm
(suffix UA)

3-pin SOT23-W
2 mm × 3 mm × 1 mm
(suffix LH)

Description

New applications for linear output Hall-effect devices, such
as displacement, angular position, and current measurement,
require high accuracy in conjunction with small package size.
The Allegro® A1324, A1325, and A1326 linear Hall-effect
sensor ICs are designed specifically to achieve both goals. This
temperature-stable device is available in a miniature surface
mount package (SOT23W) and an ultra-mini through-hole
single in-line package.

These ratiometric Hall effect sensor ICs provide a voltage
output that is proportional to the applied magnetic field. They
feature a quiescent voltage output of 50% of the supply voltage.
The A1324/25/26 feature factory programmed sensitivities of

5.0 mV/G, 3.125 mV/G, and 2.5 mV/G, respectively.

The features of these linear devices make them ideal for use in
automotive and industrial applications requiring high accuracy,
and are guaranteed through an extended temperature range,
–40°C to 150°C.

Each BiCMOS monolithic circuit integrates a Hall element,
temperature-compensating circuitry to reduce the intrinsic
sensitivity drift of the Hall element, a small-signal high-gain
amplifier, a clamped low-impedance output stage, and a
proprietary dynamic offset cancellation technique.

Approximate footprint

Functional Block Diagram

To All Subcircuits

VCV+C

GND

Cancellation

Dynamic Offset

Sensitivity and
Sensitivity TC

These devices are available in a 3-pin ultra-mini SIP package
(UA), and a 3-pin surface mount SOT-23 style package (LH). Both
are lead (Pb) free, with 100% matte tin leadframe plating.

VOUT

Tuned Filter

Offset

Trim Control

A1324-DS, Rev. 1

A1324, A1325,

and A1326

Selection Guide

Part Number Packing

A1324LLHLX-T 10 000 pieces per reel 3-pin SOT-23W surface mount

A1324LUA-T

A1325LLHLX-T 10 000 pieces per reel 3-pin SOT-23W surface mount

A1325LUA-T

A1326LLHLX-T 10 000 pieces per reel 3-pin SOT-23W surface mount

A1326LUA-T

1

Contact Allegro® for additional packing options.

2

Contact factory for availability.

Absolute Maximum Ratings

Forward Supply Voltage V

Reverse Supply Voltage V

Forward Output Voltage V

Reverse Output Voltage V

Output Source Current I

Output Sink Current I

Operating Ambient Temperature T

Maximum Junction Temperature TJ(max) 165 ºC

Storage Temperature T

2

500 pieces per bag 3-pin ultramini SIP through hole mount

2

500 pieces per bag 3-pin ultramini SIP through hole mount

2

500 pieces per bag 3-pin ultramini SIP through hole mount

Characteristic Symbol Notes Rating Unit

Linear Hall Effect Sensor ICs with Analog Output

1

OUT(SOURCE)

OUT(SINK)

CC

RCC

OUT

ROUT

A

stg

Package

VOUT to GND 2 mA

VCC to VOUT 10 mA

L temperature range –40 to 150 ºC

Sensitivity (Typ.)

(mV/G)

5.000

3.125

2.500

8V

–0.1 V

15 V

–0.1 V

–65 to 170 ºC

Thermal Characteristics may require derating at maximum conditions, see application information

Characteristic Symbol Test Conditions* Value Unit

Package LH, on 4-layer PCB with copper limited to solder pads 228 ºC/W

Package Thermal Resistance

*Additional thermal information available on the Allegro website

R

θJA

Package LH, on 2-layer PCB with 0.463 in.2 of copper area each
side, connected by thermal vias

Package UA, on 1-layer PCB with copper limited to solder pads 165 ºC/W

Pin-out Diagrams

3

231

LH Package UA Package

Terminal List Table

Name

VCC 1 1

VOUT 2 3

GND 3 2 Ground

Number

LH UA

Input power supply; tie to GND with
bypass capacitor

Output signal; also used for
programming

110 ºC/W

Function

Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

2

A1324, A1325,

and A1326

Linear Hall Effect Sensor ICs with Analog Output

OPERATING CHARACTERISTICS Valid throughout T

range, C

A

= 0.1 μF, VCC = 5 V; unless otherwise noted

BYPASS

Characteristics Symbol Test Conditions Min. Typ. Max. Unit

Electrical Characteristics

Supply Voltage V

Supply Current I

Power-On Time2 t

Supply Zener Clamp Voltage V

CC

No load on VOUT – 6.9 9 mA

CC

TA = 25°C, CL (PROBE) = 10 pF – 32 – μs

PO

TA = 25°C, ICC = 12 mA 6 8.3 – V

Z

4.5 5.0 5.5 V

Internal Bandwidth BWiSmall signal, –3 dB – 17 – kHz

Chopping Frequency

3

f

TA = 25°C – 400 – kHz

C

Output Characteristics

Quiescent Voltage Output V

OUT(Q)

Output Referred Noise V

Input Referred RMS Noise Density V

DC Output Resistance R

Output Load Resistance R

Output Load Capacitance C

V

Output Saturation Voltage

OUT(sat)HIGH

V

OUT(sat)LOW

NRMS

B = 0 G, TA = 25°C 2.425 2.500 2.575 V

A1324, TA = 25°C, C

A1325, TA = 25°C, C

N

A1326, TA = 25°C, C

TA = 25°C, C
f << BW

OUT

BYPASS

i

= 0.1 μF – 7.0 – mV

BYPASS

= 0.1 μF – 4.4 – mV

BYPASS

= 0.1 μF – 3.5 – mV

BYPASS

= open, no load on VOUT,

– 1.3 – mG/√Hz

–< 1– Ω

VOUT to VCC 4.7 – – kΩ

L

VOUT to GND 4.7 – – kΩ

VOUT to GND – – 10 nF

L

R

PULLDOWN

R

PULLUP

= 4.7 kΩ, VCC = 5 V 4.7 – – V

= 4.7 kΩ, VCC = 5 V – – 0.30 V

Magnetic Characteristics

A1324, TA = 25°C 4.750 5.000 5.250 mV/G

Sensitivity Sens

Sensitivity Temperature Coefficient TC

A1325, TA = 25°C 2.969 3.125 3.281 mV/G

A1326, T

LH package; programmed at TA = 150°C,
calculated relative to Sens at 25°C

Sens

UA package; programmed at T
calculated relative to Sens at 25°C

= 25°C 2.375 2.500 2.625 mV/G

A

– 0 – %/°C

= 150°C,

A

– 0.03 – %/°C

Error Components

Sensitivity Drift at Maximum Ambient
Operating Temperature

Sensitivity Drift at Minimum Ambient
Operating Temperature

∆Sens

∆Sens

LH package; from hot to room temperature –5 – 5 %

(TAmax)

UA package; from hot to room temperature –2.5 – 7.5 %

LH package; from cold to room temperature –3.5 – 8.5 %

(TAmin)

UA package; from cold to room temperature –6 – 4 %

1

(p-p)

(p-p)

(p-p)

Continued on the next page…

Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

3

A1324, A1325,

and A1326

Linear Hall Effect Sensor ICs with Analog Output

OPERATING CHARACTERISTICS (continued) Valid throughout T

range, C

A

BYPASS

Characteristics Symbol Test Conditions Min. Typ. Max. Unit

Error Components (continued)

Quiescent Voltage Output Drift
Through Temperature Range

Linearity Sensitivity Error Lin

Symmetry Sensitivity Error Sym

Ratiometry Quiescent Voltage
Output Error

4

∆V

Rat

OUT(Q)

ERR

ERR

VOUT(Q)

Defined in terms of magnetic flux density, B –10 – 10 G

Throughout guaranteed supply voltage range
(relative to VCC = 5 V)

Throughout guaranteed supply voltage range

Ratiometry Sensitivity Error

Sensitivity Drift Due to Package
Hysteresis

1

1 G (gauss) = 0.1 mT (millitesla).

2

See Characteristic Definitions section.

3

fC varies up to approximately ±20% over the full operating ambient temperature range and process.

4

Percent change from actual value at VCC = 5 V, for a given temperature.

4

Rat

∆Sens

(relative to VCC = 5 V), TA = 25°C and 150°C

Sens

Throughout guaranteed supply voltage range
(relative to V

TA = 25°C, after temperature cycling – ±2 – %

PKG

= 5 V), TA = –40°C

CC

= 0.1 μF, VCC = 5 V; unless otherwise noted

1

–1.5 – 1.5 %

–1.5 – 1.5 %

–1.3 – 1.3 %

–1.5 – 1.5 %

–2 – 2 %

Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

4