3141
THRU
3144
SENSITIVE HALL-EFFECT SWITCHES
FOR HIGH-TEMPERATURE OPERATION
These Hall-effect switches are monolithic integrated circuits with
tighter magnetic specifications, designed to operate continuously over
extended temperatures to +150°C, and are more stable with both
temperature and supply voltage changes. The unipolar switching
characteristic makes these devices ideal for use with a simple bar or rod
magnet. The four basic devices (3141, 3142, 3143, and 3144) are
identical except for magnetic switch points.
Each device includes a voltage regulator for operation with supply
voltages of 4.5 to 24 volts, reverse battery protection diode, quadratic
Hall-voltage generator, temperature compensation circuitry, small-
signal amplifier, Schmitt trigger, and an open-collector output to sink
up to 25 mA. With suitable output pull up, they can be used with
bipolar or CMOS logic circuits. The A3141– and A3142– are im-
proved replacements for the UGN/UGS3140–; the A3144– is the
improved replacement for the UGN/UGS3120–.
The first character of the part number suffix determines the device
operating temperature range. Suffix ‘E–’ is for the automotive and
industrial temperature range of -40°C to +85°C. Suffix ‘L–’ is for the
automotive and military temperature range of -40°C to +150°C. Three
package styles provide a magnetically optimized package for most
applications. Suffix ‘–LT’ is a miniature SOT-89/TO-243AA transis-
tor package for surface-mount applications; suffix ‘–U’ is a three-lead
plastic mini-SIP, while suffix ‘–UA’ is a three-lead ultra-mini-SIP.
Data Sheet
27621.6A*
V
X
CC
1
2
3
GROUND
Dwg. PH-003A
Pinning is shown viewed from branded side.
OUTPUT
SUPPLY
FEATURES and BENEFITS
ABSOLUTE MAXIMUM RATINGS
at T
A
= +25
°
C
Supply Voltage, V
CC
............................
28 V
Reverse Battery Voltage, V
RCC
...........
-35 V
Magnetic Flux Density, B ..........
Unlimited
Output OFF Voltage, V
OUT
..................
28 V
Reverse Output Voltage, V
OUT
...........
-0.5 V
Continuous Output Current, I
OUT
......
25 mA
Operating Temperature Range, T
A
Suffix ‘E–’ ..................
-40
°
C to +85
°
C
Suffix ‘L–’ ................
-40
°
C to +150
°
C
Storage Temperature Range,
T
S
..............................
-65
°
C to +170
°
C
s
s
s
s
s
s
s
s
Superior Temp. Stability for Automotive or Industrial Applications
4.5 V to 24 V Operation … Needs Only An Unregulated Supply
Open-Collector 25 mA Output … Compatible with Digital Logic
Reverse Battery Protection
Activate with Small, Commercially Available Permanent Magnets
Solid-State Reliability
Small Size
Resistant to Physical Stress
The A3141xU, A3142xU, A3143xU,
and A3144xU are not for new design.
Always order by complete part number, e.g.,
A3141ELT
.
3141
THRU
3144
SENSITIVE
HALL-EFFECT SWITCHES
FOR HIGH-TEMP. OPERATION
FUNCTIONAL BLOCK DIAGRAM
1
V
CC
REG.
X
3
OUTPUT
GROUND
2
Dwg. FH-005-2
ELECTRICAL CHARACTERISTICS at V
CC
= 8 V over operating temperature range.
Limits
Characteristic
Supply Voltage
Output Saturation Voltage
Output Leakage Current
Supply Current
Output Rise Time
Output Fall Time
Symbol
V
CC
V
OUT(SAT)
I
OFF
I
CC
t
r
t
f
Test Conditions
Operating
I
OUT
= 20 mA, B > B
OP
V
OUT
= 24 V, B < B
RP
B < B
RP
(Output OFF)
R
L
= 820
Ω,
C
L
= 20 pF
R
L
= 820
Ω,
C
L
= 20 pF
Min.
4.5
175
<1.0
4.4
0.04
0.18
Typ.
Max.
24
400
10
9.0
2.0
2.0
Units
V
mV
µA
mA
µs
µs
MAGNETIC CHARACTERISTICS in gauss over operating supply voltage range.
Part Numbers*
A3141–
Characteristic
B
OP
at T
A
= 25°C
over operating temp. range
B
RP
at T
A
= 25°C
over operating temp. range
B
hys
at T
A
= 25°C
over operating temp. range
Min.
50
30
10
10
20
20
Typ.
100
100
45
45
55
55
Max.
160
175
130
145
80
80
A3142–
Min. Typ.
130
115
75
60
30
30
180
180
125
125
55
55
Max.
230
245
175
190
80
80
Min.
220
205
165
150
30
30
A3143–
Typ.
280
280
225
225
55
55
Max.
340
355
285
300
80
80
Min.
70
35
50
25
20
20
55
55
A3144–
Typ.
Max.
350
450
330
430
NOTES: Typical values are at T
A
= +25°C and V
CC
= 8 V.
B
OP
= operate point (output turns ON); B
RP
= release point (output turns OFF); B
hys
= hysteresis (B
OP
- B
RP
).
*Complete part number includes a suffix to identify operating temperature range (E- or L-) and package type ( -LT, -U, or -UA).
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 1993, 1999, Allegro MicroSystems, Inc.
3141
THRU
3144
SENSITIVE
HALL-EFFECT SWITCHES
FOR HIGH-TEMP. OPERATION
SENSOR LOCATIONS
(
±
0.005” [0.13 mm] die placement)
TYPICAL OPERATING CHARACTERISTICS (cont.)
CHANGE IN OPERATE POINT
20
Suffix “LT”
ACTIVE AREA DEPTH
0.0305"
0.775 mm
NOM
0.089"
2.26 mm
CHANGE IN OPERATE POINT IN GAUSS
0.043"
1.09 mm
15
T
A
= +25°C
10
A
1
2
3
5.0
Dwg. MH-008-2D
Suffix “U”
ACTIVE AREA DEPTH
0.0165"
0.42 mm
NOM
0.091"
2.31 mm
0
-5.0
0
5
10
15
20
25
SUPPLY VOLTAGE IN VOLTS
0.070"
1.78 mm
Dwg. GH-042-1
A
BRANDED
SURFACE
1
2
3
OPERATION
The output of these devices (pin 3) switches low when the magnetic field
at the Hall sensor exceeds the operate point threshold (B
OP
). At this point, the
output voltage is V
OUT(SAT)
. When the magnetic field is reduced to below the
release point threshold (B
RP
), the device output goes high. The difference in
the magnetic operate and release points is called the hysteresis (B
hys
) of the
device. This built-in hysteresis allows clean switching of the output even in
the presence of external mechanical vibration and electrical noise.
Dwg. MH-002-2C
Suffix “UA”
ACTIVE AREA DEPTH
0.0195"
0.50 mm
NOM
0.082"
2.07 mm
A
BRANDED
SURFACE
1
2
3
0.055"
1.39 mm
Dwg. MH-011-10A
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000