DESCRIPTION
The A1152-F, A1153-F, A1155-F, and A1156-F comprise a
family of two-wire, unipolar, Hall-effect switches, which are
factory-trimmed to optimize magnetic switchpoint accuracy.
These devices are produced on the Allegro™ advanced
BiCMOS wafer fabrication process, which implements a
high-frequency, 4-phase, chopper stabilization technique. This
technique achieves magnetic stability over the full operating
temperature range, and eliminates offsets inherent in devices
with a single Hall element that are exposed to harsh application
environments.
The A115x family has a number of automotive applications.
These include sensing seat track position, seat belt buckle
presence, hood/trunk latching, and shift selector position.
Two-wire unipolar switches are particularly advantageous in
cost-sensitive applications because they require one less wire
for operation versus the more traditional open-collector output
switches. Additionally, the system designer inherently gains
diagnostics because there is always output current flowing,
which should be in either of two narrow ranges. Any current
level not within these ranges indicates a fault condition.
A1152-F-DS, Rev. 4
MCO-0000556
FEATURES AND BENEFITS
▪AEC-Q100automotivequalified
▪Factory-settemperaturecoefficient(TC)forusewith
ferrite magnets
▪High-speed,4-phasechopperstabilization
▪Lowswitchpointdriftthroughouttemperaturerange
▪Lowsensitivitytothermalandmechanicalstresses
▪On-chipprotection
▫Supplytransientprotection
▫Reverse-batteryprotection
▫On-boardvoltageregulator
▫3to24Voperation
▪Solid-statereliability
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
Continued on the next page…
Functional Block Diagram
PACKAGE: 2-Pin, Ultra-Mini SIP (suffix UB)
Not to scale
Amp
Regula
To all subcircuits
tor
Schmitt
Trigger
Polarity
Low-Pass
Filter
VCC
GND
0.1µF
Clock/Logic
Dynamic Offset
Cancellation
Sample and Hold
1.5 mm × 4 mm × 4 mm
Continued on the next page…
A1152-F, A1153-F, A1155-F, and A1156-F
January 16, 2019
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
2
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
The UB is a 2-pin, ultra-mini, single inline package (SIP) for
through-holemounting,anditislead(Pb)free,with100%matte-
tin leadframe plating.
DESCRIPTION (CONTINUED)
▪RobustEMCandESDperformance
▪Industry-leadingISO7637-2performancethroughuseof
proprietary,40Vclampingstructures
▪ExtendedOperatingAmbienttemperaturerange,
–40°Cto150°C
▪UBpackagewithintegrated0.1µFbypasscapacitor
FEATURES AND BENEFITS (CONTINUED)
SELECTION GUIDE
Part Number Packing Package
Output (ICC) in
South Polarity
Field
Supply Current
at ICC(L)
(mA)
Magnetic Operate
Point, BO P,
at TA = 25°C
(G)
A1152LUBTN-F-T 13-in. reel, 4000 pieces/reel 2-pin SIP through-hole Low 5 to 6.9 58 to 100
A1153LUBTN-F-T 13-in. reel, 4000 pieces/reel 2-pin SIP through-hole High 5 to 6.9 58 to 100
A1155LUBTN-F-T 13-in. reel, 4000 pieces/reel 2-pin SIP through-hole Low 5 to 6.9 16 to 60
A1156LUBTN-F-T 13-in. reel, 4000 pieces/reel 2-pin SIP through-hole High 5 to 6.9 16 to 60
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
3
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
ABSOLUTE MAXIMUM RATINGS
Characteristic Symbol Notes Rating Unit
Forward Supply Voltage VCC 28 V
Reverse Supply Voltage VRCC –18 V
Magnetic Flux Density B Unlimited G
Operating Ambient Temperature TARange L –40 to 150 °C
Maximum Junction Temperature TJ(max) 165 °C
Storage Temperature Tstg –65 to 170 °C
Pinout Diagram
1
2
UB Package
Terminal List Table
Number Name Function
1 VCC Input power supply
2 GND Ground terminal
INTERNAL DISCRETE CAPACITOR RATINGS
Characteristic Symbol Notes Rating Unit
Rated Normal Capacitance CSUPPLY Connected between VCC and GND 0.1 µF
Rated Voltage VCSUPPLY 50 V
Rated Capacitor Tolerance ±10 %
Temperature Designator X7R –
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
4
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
ELECTRICAL CHARACTERISTICS: Valid at TA = –40°C to 150°C, TJ < TJ(max), CBYP = 0.01 µF (excluding UB), through
operating supply voltage range, unless otherwise noted
Characteristics Symbol Test Conditions Min. Typ. Max. Unit
Supply Voltage
1,2 VCC Operating, TJ ≤ 165 °C 3.0 – 24 V
Supply Current
ICC(L)
A1152, A1155 B > BOP 5 – 6.9 mA
A1153, A1156 B < BRP
ICC(H)
A1152, A1155 B < BRP 12 – 17 mA
A1153, A1156 B > BOP
Supply Zener Clamp Voltage VZ(sup) ICC(L)(max) + 3 mA, TA = 25°C 28 – – V
Supply Zener Clamp Current IZ(sup) VZ(sup) = 28 V – – ICC(L)(max)
+ 3 mA mA
Reverse Supply Current IRCC VRCC = –18 V – – –1.6 mA
Output Slew Rate
3di/dt Integrated bypass capacitor, capacitance of
probe CS = 20 pF – 0.22 – mA / µs
Chopping Frequency fc– 700 – kHz
Power-Up Time
4,5 ton
A1152, A1155 B > BOP + 10 G – – 25 µs
A1153, A1156 B < BRP – 10 G
Power-Up State
2,4,6,7 POS ton < ton(max) , VCC slew rate > 25 mV / µs – ICC(H) – –
1 VCC represents the generated voltage between the VCC pin and the GND pin.
2 The VCC slew rate must exceed 600 mV/ms from 0 to 3 V. A slower slew rate through this range can affect device performance.
3 Measured without bypass capacitor between VCC and GND. Use of a bypass capacitor results in slower current change.
4 Power-Up Time is measured without and with bypass capacitor of 0.01 µF. Adding a larger bypass capacitor would cause longer Power-Up Time.
5 Guaranteed by characterization and design.
6 Power-Up State as defined is true only with a VCC slew rate of 25 mV / µs or greater.
7 For t > ton and BRP < B < BOP , Power-Up State is not defined.
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
5
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
MAGNETIC CHARACTERISTICS1: Valid at TA = –40°C to 150°C (TJ < TJ (max)), unless otherwise noted
Characteristics Symbol Test Conditions Min. Typ. Max. Unit2
MAGNETIC CHARACTERISTICS
Magnetic Operating Point BOP
1152,
1153
TA = –40°C 72 – 118 G
TA = 25°C 58 – 100 G
TA = 150°C 37 – 68 G
1155,
1156
TA = –40°C 23 – 73 G
TA = 25°C 16 – 60 G
TA = 150°C 9 – 49 G
Magnetic Release Point BRP
1152,
1153
TA = –40°C 56 – 103 G
TA = 25°C 46 – 85 G
TA = 150°C 22 – 58 G
1155,
1156
TA = –40°C 6 – 53 G
TA = 25°C 4 – 45 G
TA = 150°C 4 – 39 G
Hysteresis BHYS
1152,
1153,
1155,
1156
TA = –40°C 5 – 30 G
TA = 25°C 5 – 30 G
TA = 150°C 5 – 30 G
1 Relative values of B use the algebraic convention, where positive values indicate south magnetic polarity, and negative values indicate north
magnetic polarity; therefore greater B values indicate a stronger south polarity field (or a weaker north polarity field, if present).
2 1 G (gauss) = 0.1 mT (millitesla).
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
6
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
THERMAL CHARACTERISTICS: may require derating at maximum conditions; see application information
Characteristic Symbol Test Conditions* Value Unit
Package Thermal Resistance RθJA Package UB, on 1-layer PCB with copper limited to solder pads 213 °C/W
*Additional thermal information available on the Allegro website
UB Power Derating Curve
UB Power Dissipation versus Ambient Temperature
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
7
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Supply Voltage, V
CC
(V)
Supply Current, ICC(H) (mA)
17
16
15
14
13
12
2 6 10 14 18 22 26
TA = 150°C
TA = –40°C
TA = 25°C
Average Supply Current (High) versus Supply Voltage
A1150/A1152/A1153/A1155/A1156/A1157/A1158
VCC = 3.0 V
VCC = 24 V
-60 -40 -20 0 20 40 60 80 100 140120 160
Ambient Temperature, T
A
(°C)
Supply Current, ICC(H) (mA)
17
16
15
14
13
12
Average Supply Current (High) versus Temperature
A1150/A1152/A1153/A1155/A1156/A1157/A1158
5.0
4.5
4.0
3.5
3.0
2.5
2.0
Supply Current, ICC(L) (mA)
Supply Voltage, VCC (V)
2 6 10 14 18 22 26
TA = 150°C
TA = –40°C
TA = 25°C
5.0
4.5
4.0
3.5
3.0
2.5
2.0
Average Supply Current (Low) versus Supply Voltage
A1150/A1157/A1158
5.0
4.5
4.0
3.5
3.0
2.5
2.0
Ambient Temperature, TA (°C)
Supply Current, ICC(L) (mA)
-60 -40 -20 0 20 40 60 80 100 140120 160
VCC = 3.0 V
VCC = 24 V
5.0
4.5
4.0
3.5
3.0
2.5
2.0
Ambient Temperature, TA (°C)
-60 -40 -20 0 20 40 60 80 100 140120 160
VCC = 3.0 V
VCC = 24 V
Average Supply Current (Low) versus Temperature
A1150/A1157/A1158
TA = 150°C
TA = –40°C
TA = 25°C
7.0
6.5
6.0
5.5
5.0
2 6 10 14 18 22 26
Supply Voltage, VCC (V)
Supply Current, ICC(L) (mA)
Average Supply Current (Low) versus Supply Voltage
A1152/A1153/A1155/A1156
VCC = 3.0 V
VCC = 24 V
7.0
6.5
6.0
5.5
5.0
-60 -40 -20 0 20 40 60 80 100 140120 160
Ambient Temperature, TA (°C)
Supply Current, ICC(L) (mA)
Average Supply Current (Low) versus Temperature
A1152/A1153/A1155/A1156
CHARACTERISTIC PERFORMANCE
A1155-F/A1156-F
A1152-F/A1153-F
A1152-F/A1153-F A1155-F/A1156-F
A1155-F/A1156-FA1152-F/A1153-F
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
8
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
30
45
60
75
90
105
120
-60 -40 -20 020 40 60 80 100 120 140 160
Applied Flux Density at
Operate Point, B
OP
(G)
Ambient Temperature, T
A
(°C)
A1152-F/A1153-F
Average Operate Point versus Temperature
VCC = 3.0 V
VCC = 24 V
5
20
35
50
65
80
-60 -40 -20 020 40 60 80 100 120 140 160
Ambient Temperature, TA(°C)
A1155-F/A1156-F
Average Operate Point versus Temperature
VCC = 3.0 V
VCC = 24 V
20
35
50
65
80
95
110
-60 -40 -20 020 40 60 80 100 120 140 160
Applied Flux Density at
Release Point, BRP (G)
Ambient Temperature, TA(°C)
A1152-F/A1153-F
Average Release Point versus Temperature
VCC = 3.0 V
VCC = 24 V
0
10
20
30
40
50
60
-60 -40 -20 020 40 60 80 100 120 140 160
Applied Flux Density at
Release Point, B
RP
(G)
Ambient Temperature, T
A
(°C)
A1155-F/A1156-F
Average Release Point versus Temperature
VCC = 3.0 V
VCC = 24 V
5
10
15
20
25
30
-60 -40 -20 020 40 60 80 100 120 140 160
Applied Flux Density at
Switchpoint Hysteresis, B
HYS
(G)
Ambient Temperature, T
A
(°C)
A1152-F/A1153-F
Average Switchpoint Hysteresis versus Temperature
VCC = 3.0 V
VCC = 24 V
5
10
15
20
25
30
-60 -40 -20 020 40 60 80 100 120 140 160
Applied Flux Density at
Switchpoint Hysteresis, B
HYS
(G)
Ambient Temperature, T
A
(°C)
A1155-F/A1156-F
Average Switchpoint Hysteresis versus Temperature
VCC = 3.0 V
VCC = 24 V
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
9
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
FUNCTIONAL DESCRIPTION
B
OP
B
RP
B
HYS
I
CC(H)
I
CC
I
CC(L)
Switch to Low
Switch to High
B+
B–
I+
0
(A) Hysteresis curve for A1152 and A1155
B
OP
B
RP
B
HYS
I
CC(H)
I
CC
I
CC(L)
Switch to High
Switch to Low
B+
I+
B–
0
(B) Hysteresis curve for A1153 and A1156
TheA1152andA1155output,ICC, switches low after the mag-
neticfieldattheHallsensorICexceedstheoperatepointthresh-
old, BOP. When the magnetic field is reduced to below the release
point threshold, BRP, the device output goes high. This is shown
in Figure 1, panel A.
Inthecaseofthereverseoutputpolarity,asintheA1153and
A1156, the device output switches high after the magnetic field
attheHallsensorICexceedstheoperatepointthreshold,BOP.
When the magnetic field is reduced to below the release point
threshold, BRP,thedeviceoutputgoeslow(panelB).
The difference between the magnetic operate and release points
is called the hysteresis of the device, BHYS
. This built-in hyster-
esis allows clean switching of the output even in the presence of
external mechanical vibration and electrical noise.
Figure 1: Alternative Switching Behaviors Available in the A115x Device Family.
On the horizontal axis, the B+ direction indicates increasing south polarity magnetic field strength, and the B– direction indicates
decreasing south polarity field strength (including the case of increasing north polarity).
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
10
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
GND
A115x
VCC
V+
0.1 µF
ECU
RSENSE
GND
A115x
VCC
V+
RSENSE
0.1 µF
Figure 2: Typical Application Circuits
(A) Low side sensing (B) High side sensing
Amp
Regulator
Clock/Logic
Hall Element
Sample and
Hold
Low-Pass
Filter
Chopper Stabilization Technique
When using Hall-effect technology, a limiting factor for
switchpoint accuracy is the small signal voltage developed
across the Hall element. This voltage is disproportionally small
relative to the offset that can be produced at the output of the
HallsensorIC.Thismakesitdifficulttoprocessthesignalwhile
maintaining an accurate, reliable output over the specified oper-
ating temperature and voltage ranges. Chopper stabilization is
a unique approach used to minimize Hall offset on the chip. The
Allegrotechnique,namelyDynamicQuadratureOffsetCancella-
tion, removes key sources of the output drift induced by thermal
and mechanical stresses. This offset reduction technique is based
on a signal modulation-demodulation process. The undesired
offset signal is separated from the magnetic field-induced signal
in the frequency domain, through modulation. The subsequent
demodulation acts as a modulation process for the offset, causing
the magnetic field-induced signal to recover its original spectrum
atbaseband,whiletheDCoffsetbecomesahigh-frequencysig-
nal. The magnetic-sourced signal then can pass through a low-
passfilter,whilethemodulatedDCoffsetissuppressed.The
chopperstabilizationtechniqueusesa350kHzhighfrequency
clock. For demodulation process, a sample and hold technique is
used, where the sampling is performed at twice the chopper fre-
quency. This high-frequency operation allows a greater sampling
rate, which results in higher accuracy and faster signal-process-
ing capability. This approach desensitizes the chip to the effects
of thermal and mechanical stresses, and produces devices that
have extremely stable quiescent Hall output voltages and precise
recoverability after temperature cycling. This technique is made
possible through the use of a BiCMOS process, which allows
the use of low-offset, low-noise amplifiers in combination with
high-density logic integration and sample-and-hold circuits.
Figure 3: Chopper Stabilization Circuit (Dynamic Quadrature Offset Cancellation)
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
11
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
The device must be operated below the maximum junction tem-
perature of the device, TJ(max). Under certain combinations of
peak conditions, reliable operation may require derating supplied
power or improving the heat dissipation properties of the appli-
cation. This section presents a procedure for correlating factors
affecting operating TJ.(Thermaldataisalsoavailableonthe
AllegroMicroSystemsWebsite.)
ThePackageThermalResistance,RθJA, is a figure of merit sum-
marizing the ability of the application and the device to dissipate
heatfromthejunction(die),throughallpathstotheambientair.
ItsprimarycomponentistheEffectiveThermalConductivity,K,
of the printed circuit board, including adjacent devices and traces.
Radiationfromthediethroughthedevicecase,RθJC, is relatively
small component of RθJA. Ambient air temperature, TA, and air
motion are significant external factors, damped by overmolding.
Theeffectofvaryingpowerlevels(PowerDissipation,PD),can
be estimated. The following formulas represent the fundamental
relationships used to estimate TJ,atPD.
PD = VIN × IIN (1)
ΔT = PD × RθJA (2)
TJ = TA + ΔT (3)
For example, given common conditions such as: TA= 25°C,
VCC = 12V,ICC = 4 mA, and RθJA =140°C/W,then:
PD = VCC × ICC = 12 V × 4 mA = 48 mW
ΔT = PD × RθJA = 48 mW × 140 °C/W = 7°C
TJ = TA + ΔT = 25°C + 7°C = 32°C
A worst-case estimate, PD(max),representsthemaximumallow-
ablepowerlevel(VCC(max),ICC(max)),withoutexceeding
TJ(max), at a selected RθJA and TA.
Example:ReliabilityforVCC at TA
=
150°C,packageUA,usinga
low-KPCB.
Observe the worst-case ratings for the device, specifically:
RθJA=
213°C/W,TJ(max) =
165°C,VCC(max)
= 24V,and
ICC(max) = 17 mA.
Calculate the maximum allowable power level, PD(max). First,
invert equation 3:
ΔTmax = TJ(max) – TA = 165
°C
–
150
°C = 15
°C
This provides the allowable increase to TJ resulting from internal
power dissipation. Then, invert equation 2:
PD(max) = ΔTmax ÷ RθJA = 15°C ÷ 213 °C/W = 70.5 mW
Finally, invert equation 1 with respect to voltage:
VCC(est) = PD(max) ÷ ICC(max) = 70.5 mW ÷ 17 mA = 4.15 V
The result indicates that, at TA, the application and device can
dissipateadequateamountsofheatatvoltages≤VCC(est).
CompareVCC(est)toVCC(max).IfVCC(est)≤VCC(max),thenreli-
ableoperationbetweenVCC(est)andVCC(max)requiresenhanced
RθJA.IfVCC(est)≥VCC(max),thenoperationbetweenVCC(est)
andVCC(max)isreliableundertheseconditions.
Power Derating
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
12
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Package UB, 2-Pin SIP
Mold Ejector
Pin Indent
0.25 REF
0.30 REF
4 X 2.50 REF
4 X 7.37 REF
4 X 0.85 REF
4 X 0.85 REF
0.38 REF
0.25 REF
45°
0.85 ±0.07
0.85 ±0.07
21
B
4 X 10°
A
Branded
Face
0.25 +0.07
–0.03
0.42 ±0.10
4.00
4.00
1.00 ±0.10
1.80
±0.10
2.54 REF
12.20 ±0.10
1.50 ±0.05
1.50 ±0.05
A
B
C
C
DBranding scale and appearance at supplier discretion
F
F
E
E
1.75
2.00
E
E
For Reference Only – Not for Tooling Use
(Reference DWG-9070)
Dimensions in millimeters
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
Dambar removal protrusion (8X)
Gate and tie bar burr area
Active Area Depth, 0.38 mm REF
Hall element; not to scale
Thermoplastic Molded Lead Bar for alignment during shipment
4.00 +0.06
–0.05
+0.06
–0.07
1.80+0.06
–0.07
+0.06
–0.05
D
= Supplier emblem
= Last three digits of device part number
= Last 2 digits of year of manufacture
= Week of manufacture
= Lot number
N
Y
W
L
Standard Branding Reference View
YYWW
LLLL
NNN
Chopper-Stabilized, Two-Wire
Hall-Effect Switches
13
A1152-F, A1153-F,
A1155-F, and A1156-F
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
For the latest version of this document, visit our website:
www.allegromicro.com
Copyright ©2019, Allegro MicroSystems, LLC
Allegro MicroSystems, LLC reserves the right to make, from time to time, such departures from the detail specifications as may be required to
permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that
the information being relied upon is current.
Allegro’s products are not to be used in any devices or systems, including but not limited to life support devices or systems, in which a failure of
Allegro’s product can reasonably be expected to cause bodily harm.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, LLC assumes no responsibility for its
use; nor for any infringement of patents or other rights of third parties which may result from its use.
Copies of this document are considered uncontrolled documents.
Revision History
Number Date Description
– September 29, 2014 Initial Release
1 April 2, 2015 Updated branding info on package drawing
2 September 21, 2015 Added AEC-Q100 qualification under Features and Benefits
3 June 21, 2016 Corrected internal discrete capacitor ratings
4 January 16, 2019 Minor editorial updates.