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
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 operate 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.
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)
Approximate footprint
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.
Functional Block Diagram
V+
To All Subcircuits
VCC
Dynamic Offset
Cancellation
Tuned Filter
VOUT
Sensitivity and
Sensitivity TC
Offset
Trim Control
GND
A1324-DS, Rev. 4
A1324, A1325,
and A1326
Selection Guide
Part Number
A1324LLHLT-T
A1324LLHLX-T
A1324LUA-T
2
A1325LLHLT-T
A1325LLHLX-T
A1325LUA-T
2
A1326LLHLT-T
A1326LLHLX-T
A1326LUA-T
2
1
Contact Allegro
™
2
Contact
Linear Hall Effect Sensor ICs with Analog Output
Packing
1
3 000 pieces per reel
10 000 pieces per reel
500 pieces per bag
3 000 pieces per reel
10 000 pieces per reel
500 pieces per bag
3 000 pieces per reel
10 000 pieces per reel
500 pieces per bag
Package
3-pin SOT-23W surface mount
3-pin SOT-23W surface mount
3-pin ultramini SIP through hole mount
3-pin SOT-23W surface mount
3-pin SOT-23W surface mount
3-pin ultramini SIP through hole mount
3-pin SOT-23W surface mount
3-pin SOT-23W surface mount
3-pin ultramini SIP through hole mount
Sensitivity (Typ.)
(mV/G)
5.000
3.125
2.500
for additional packing options.
factory for availability.
Absolute Maximum Ratings
Characteristic
Forward Supply Voltage
Reverse Supply Voltage
Forward Output Voltage
Reverse Output Voltage
Output Source Current
Output Sink Current
Operating Ambient Temperature
Maximum Junction Temperature
Storage Temperature
Symbol
V
CC
V
RCC
V
OUT
V
ROUT
I
OUT(SOURCE)
I
OUT(SINK)
T
A
T
J
(max)
T
stg
VOUT to GND
VCC to VOUT
L temperature range
Notes
Rating
8
–0.1
15
–0.1
2
10
–40 to 150
165
–65 to 170
Unit
V
V
V
V
mA
mA
ºC
ºC
ºC
Thermal Characteristics
may require derating at maximum conditions, see application information
Characteristic
Symbol
Test Conditions*
Package LH, on 4-layer PCB with copper limited to solder pads
Package Thermal Resistance
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
*Additional thermal information available on the Allegro website
Value
228
110
165
Unit
ºC/W
ºC/W
ºC/W
Pin-out Diagrams
3
Terminal List Table
Name
VCC
VOUT
Number
LH
1
2
3
UA
1
3
2
Function
Input power supply; tie to GND with
bypass capacitor
Output signal; also used for
programming
Ground
1
2
LH Package
1
2
3
GND
UA Package
Allegro MicroSystems, LLC
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
A
range, C
BYPASS
= 0.1 µF, V
CC
= 5 V; unless otherwise noted
Characteristics
Electrical Characteristics
Supply Voltage
Supply Current
Power-On Time
2
Supply Zener Clamp Voltage
Internal Bandwidth
Chopping Frequency
3
Output Characteristics
Quiescent Voltage Output
Output Referred Noise
V
OUT(Q)
V
N
B = 0 G, T
A
= 25°C
A1324, T
A
= 25°C, C
BYPASS
= 0.1 µF
A1325, T
A
= 25°C, C
BYPASS
= 0.1 µF
A1326, T
A
= 25°C, C
BYPASS
= 0.1 µF
Input Referred RMS Noise Density
DC Output Resistance
Output Load Resistance
Output Load Capacitance
Output Saturation Voltage
Magnetic Characteristics
A1324, T
A
= 25°C
Sensitivity
Sens
A1325, T
A
= 25°C
A1326, T
A
= 25°C
Sensitivity Temperature Coefficient
Error Components
Sensitivity Drift at Maximum Ambient
Operating Temperature
Sensitivity Drift at Minimum Ambient
Operating Temperature
∆Sens
(TAmax)
∆Sens
(TAmin)
Symbol
V
CC
I
CC
t
PO
V
Z
BW
i
f
C
Test Conditions
Min.
4.5
Typ.
5.0
6.9
32
8.3
17
400
2.500
7.0
4.4
3.5
1.3
<1
–
–
–
–
–
5.000
3.125
2.500
0
0.03
Max.
5.5
9
–
–
–
–
2.575
–
–
–
–
–
–
–
10
–
0.30
5.250
3.281
2.625
–
–
Unit
1
V
mA
µs
V
kHz
kHz
V
mV
(p-p)
mV
(p-p)
mV
(p-p)
mG/√Hz
Ω
kΩ
kΩ
nF
V
V
mV/G
mV/G
mV/G
%/°C
%/°C
No load on VOUT
T
A
= 25°C, C
L
(PROBE) = 10 pF
T
A
= 25°C, I
CC
= 12 mA
Small signal, –3 dB
T
A
= 25°C
–
–
6
–
–
2.425
–
–
–
–
–
V
NRMS
R
OUT
R
L
C
L
T
A
= 25°C, C
BYPASS
= open, no load on VOUT,
f << BW
i
VOUT to VCC
VOUT to GND
VOUT to GND
4.7
4.7
–
4.7
–
4.750
2.969
2.375
–
–
V
OUT(sat)HIGH
R
PULLDOWN
= 4.7 kΩ, V
CC
= 5 V
V
OUT(sat)LOW
R
PULLUP
= 4.7 kΩ, V
CC
= 5 V
TC
Sens
LH package; programmed at T
A
= 150°C,
calculated relative to Sens at 25°C
UA package; programmed at T
A
= 150°C,
calculated relative to Sens at 25°C
LH package; from hot to room temperature
UA package; from hot to room temperature
LH package; from cold to room temperature
UA package; from cold to room temperature
–5
–2.5
–3.5
–6
–
–
–
–
5
7.5
8.5
4
%
%
%
%
Continued on the next page…
Allegro MicroSystems, LLC
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
A
range, C
BYPASS
= 0.1 µF, V
CC
= 5 V; unless otherwise noted
Characteristics
Error Components (continued)
Quiescent Voltage Output Drift
Through Temperature Range
Linearity Sensitivity Error
Symmetry Sensitivity Error
Ratiometry Quiescent Voltage
Output Error
4
Ratiometry Sensitivity Error
4
Sensitivity Drift Due to Package
Hysteresis
1
1
2
See
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
1
∆V
OUT(Q)
Defined in terms of magnetic flux density, B
–10
–1.5
–1.5
–
–
–
–
–
–
±2
10
1.5
1.5
1.3
1.5
2
–
G
%
%
%
%
%
%
Lin
ERR
Sym
ERR
Rat
VOUT(Q)
Throughout supply voltage range (relative to
V
CC
= 5 V)
Throughout supply voltage range (relative to
V
CC
= 5 V), T
A
= 25°C and 150°C
Throughout supply voltage range (relative to
V
CC
= 5 V), T
A
= –40°C
T
A
= 25°C, after temperature cycling
–1.3
–1.5
–2
–
Rat
Sens
∆Sens
PKG
G (gauss) = 0.1 mT (millitesla).
Characteristic Definitions section.
3
f varies up to approximately ±20% over the full operating ambient temperature range and process.
C
4
Percent change from actual value at V
CC
= 5 V, for a given temperature.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
A1324, A1325,
and A1326
Linear Hall Effect Sensor ICs with Analog Output
Characteristic Definitions
Power-On Time
When the supply is ramped to its operating
voltage, the device output requires a finite time to react to an
input magnetic field. Power-On Time is defined as the time it
takes for the output voltage to begin responding to an applied
magnetic field after the power supply has reached its minimum
specified operating voltage, V
CC
(min).
V
V
CC
(typ.)
90% V
OUT
V
CC
V
OUT
age from its quiescent value. This proportionality is specified
as the magnetic sensitivity, Sens (mV/G), of the device and is
defined as:
Sens
=
V
OUT(B+)
–
V
OUT(B–)
B(+)
–
B(–)
(2)
where B(+) and B(–) are two magnetic fields with opposite
polarities.
Sensitivity Temperature Coefficient
The device sensitivity
changes with temperature, with respect to its sensitivity tem-
perature coefficient, TC
SENS
. TC
SENS
is programmed at 150°C,
and calculated relative to the nominal sensitivity programming
temperature of 25°C. TC
SENS
(%/°C) is defined as:
1
Sens
T2
– Sens
T1
TC
Sens
=
100%
×
(3)
T2–T1
Sens
T1
where T1 is the nominal Sens programming temperature of 25°C,
and T2 is the TC
SENS
programming temperature of 150°C.
The ideal value of sensitivity through the temperature range,
Sens
IDEAL(TA)
, is defined as:
Sens
IDEAL(TA)
=
Sens
T1
× (100% + TC
SENS(TA –T1)
)
(4)
V
CC
(min.)
t
1
t
2
t
PO
t
1
= time at which power supply reaches
minimum specified operating voltage
t
2
= time at which output voltage settles
within ±10% of its steady state value
under an applied magnetic field
0
+t
Quiescent Voltage Output
In the quiescent state (that is, with
no significant magnetic field: B = 0), the output, V
OUT(Q)
, equals
a ratio of the supply voltage, V
CC
, throughout the entire operat-
ing range of V
CC
and the ambient temperature, T
A
.
Quiescent Voltage Output Drift Through Temperature
Range
Due to internal component tolerances and thermal con-
siderations, the quiescent voltage output, V
OUT(Q)
, may drift from
its nominal value through the operating ambient temperature
range, T
A
. For purposes of specification, the Quiescent Voltage
Output Drift Through Temperature Range,
∆V
OUT(Q)
(mV), is
defined as:
∆V
OUT(Q)
=
V
OUT(Q)TA
–
V
OUT(Q)25°C
(1)
Sensitivity Drift Through Temperature Range
Second
order sensitivity temperature coefficient effects cause the mag-
netic sensitivity to drift from its ideal value through the operating
ambient temperature, T
A
. For purposes of specification, the sensi-
tivity drift through temperature range,
∆Sens
TC
, is defined as:
∆Sens
TC
=
Sens
TA
– Sens
IDEAL(TA)
Sens
IDEAL(TA)
×
100%
(5)
Sensitivity Drift Due to Package Hysteresis
Package
stress and relaxation can cause the device sensitivity at T
A
= 25°C
to change during or after temperature cycling. This change in
sensitivity follows a hysteresis curve.
For purposes of specification, the Sensitivity Drift Due to Pack-
age Hysteresis,
∆Sens
PKG
, is defined as:
∆Sens
PKG
=
Sens
(25°C)2
– Sens
(25°C)1
×
100%
Sens
(25°C)1
(6)
Sensitivity
The presence of a south-polarity magnetic field
perpendicular to the branded surface of the package increases the
output voltage from its quiescent value toward the supply voltage
rail. The amount of the output voltage increase is proportional
to the magnitude of the magnetic field applied. Conversely, the
application of a north polarity field will decrease the output volt-
where Sens
(25°C)1
is the programmed value of sensitivity at
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
嵌入式系统
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
