The A3240-- Hall-effect switch is an extremely temperature-stable
and stress-resistant sensor especially suited for operation over extended
temperature ranges to +150
C. Superior high-temperature performance
is made possible through dynamic offset cancellation, which reduces the
residual offset voltage normally caused by device overmolding, tempera-
ture dependencies, and thermal stress.
The device includes on a single silicon chip a voltage regulator,
Hall-voltage generator, small-signal amplifier, chopper stabilization,
Schmitt trigger, and a short-circuit protected open-collector output to
sink up to 25 mA. A south pole of sufficient strength will turn the
output on. An on-board regulator permits operation with supply voltages
of 4.2 to 24 volts.
The first character of the part number suffix determines the device
operating temperature range; suffix `E' is for -40
C to +85
C and
`L' is -40
C to +150
C. Three package styles provide a magnetically
optimized package for most applications. Suffix `LH' is a modified
SOT23W surface-mount package, `LT' is a miniature SOT89/TO-
243AA transistor package for surface-mount applications; while suffix
`UA' is a three-lead ultra-mini-SIP for through-hole mounting.
Data Sheet
27621.20
b
FEATURES
s
Resistant to Physical Stress
s
Superior Temperature Stability
s
Output Short-Circuit Protection
s
Operation From Unregulated Supply
s
Reverse Battery Protection
s
Solid-State Reliability
s
Small Size
Suffix `LT' & `UA' Pinning
(SOT89/TO-243AA & ultra-min SIP)
Pinning is shown viewed from branded side.
CHOPPER-STABILIZED, PRECISION
HALL-EFFECT SWITCH
3240
Supply Voltage, V
CC
........................ 26.5 V
Reverse Battery Voltage, V
RCC
.......... -30 V
Magnetic Flux Density, B ........... Unlimited
Output OFF Voltage, V
OUT
................. 26 V
Continuous Output Current,
I
OUT
.......................................... 25 mA*
Reverse Output Current, I
OUT
........ -50 mA
Package Power Dissipation, P
D
. See Graph
Junction Temperature, T
J
............... +1
65
C
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
*Internal current limiting is intended to protect
the device from output short circuits.
ABSOLUTE MAXIMUM RATINGS
at T
A
= +25
C
Always order by complete part number: the prefix `A' + the basic four-
digit part number + a suffix to indicate operating temperature range +
a suffix to indicate package style, e.g.,
A3240ELH .
Dwg. PH-003-2
1
SUPPLY
V
CC
GROUND
3
2
OUTPUT
X
PTCT
3240
CHOPPER-STABILIZED,
PRECISION
HALL-EFFECT SWITCH
www.allegromicro.com
3
Limits
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
Supply Voltage Range
V
CC
Operating, T
J
< 1
65
C
1
4.2
24
V
Output Leakage Current
I
OFF
V
OUT
= 24 V, B < B
RP
10
A
Output Saturation Voltage
V
OUT(SAT)
I
OUT
= 20 mA, B > B
OP
185
500
mV
Output Current Limit
I
OM
B > B
OP
30
60
mA
Power-On Time
t
po
V
CC
> 4.2 V
50
s
Chopping Frequency
f
C
340
kHz
Output Rise Time
t
r
R
L
= 820
, C
L
= 20 pF
0.2
2.0
s
Output Fall Time
t
f
R
L
= 820
, C
L
= 20 pF
0.1
2.0
s
Supply Current
I
CC
B < B
RP
, V
CC
= 12 V
3.0
6.0
mA
B > B
OP
, V
CC
= 12 V
4.0
6.0
mA
Reverse Battery Current
I
CC
V
RCC
= -30 V
-5.0
mA
Zener Voltage
V
Z
+ V
D
I
CC
= 15 mA, T
A
= 25
C
28
32
37
V
Zener Impedance
z
z
+ z
D
I
CC
= 15 mA, T
A
= 25
C
50
NOTES:1. Maximum voltage must be adjusted for power dissipation and junction temperature.
2. B
OP
= operate point (output turns on); B
RP
= release point (output turns off).
3. Typical Data is at T
A
= +25
C and V
CC
= 12 V and is for design information only.
ELECTRICAL CHARACTERISTICS over operating temperature range.
Limits
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
Operate Point
B
OP
35
50
G
Release Point
B
RP
5.0
25
G
Hysteresis
B
hys
B
OP
- B
RP
10
G
NOTES: 1. Typical Data is at T
A
= +25
C and V
CC
= 12 V and is for design information only.
2. 1 gauss (G) is exactly equal to 0.1 millitesla (mT).
MAGNETIC CHARACTERISTICS over operating supply voltage and temperature ranges.