3195
PROTECTED, HIGH-TEMP.,
ACTIVE PULL-DOWN
HALL-EFFECT LATCH
HALL-EFFECT LATCH WITH ACTIVE PULL-DOWN
X
LATCH
CC
V
1
32
3195
PROTECTED, HIGH-TEMPERATURE,
These Hall-effect latches are capable of sensing magnetic fields
while using an unprotected power supply. The A3195– can provide
position and speed information by providing a digital output for magnetic fields that exceed their predefined switch points. These devices
operate down to zero speed and have switch points that are designed
to be extremely stable over a wide operating temperature and voltage
range. The latching characteristics make them ideal for use in pulse
counting applications when used with a multi-pole ring magnet.
A 25 mA high-side driver combined with an active pull-down is especially useful for driving capacitive loads. Output short-circuit protection
allows for an increased wiring harness fault tolerance. The temperature compensated switch points, the wide operating voltage range, and
the integrated protection make these devices ideal for use in automotive applications such as transmission speed sensors and integrated
wheel bearing speed sensors.
Data Sheet
27609.15*
SUPPLY
Pinning is shown viewed from branded side.
GROUND
Dwg. PH-013
OUTPUT
ABSOLUTE MAXIMUM RATINGS
␣
Supply Voltage, VCC (100 ms) .......... 115 V*
(continuous)................................... 26 V
Reverse Battery Voltage,
V
(100 ms)............................ -100 V
RCC
(continuous)................................. -30 V
Magnetic Flux Density, B........... Unlimited
Reverse Output Voltage, V
Continuous Output Current,
I
........................... Internally Limited
OUT
Package Power Dissipation,
P
........................................ See Graph
D
Junction Temperature, T
Operating Temperature Range, T
Suffix “E–”.................... -40°C to +85°C
Suffix “L–” .................. -40
Storage Temperature, T
......... -0.5 V
OUT
................. 170°C
J
A
°C to +150°C
................. 170°C
S
Each monolithic device contains an integrated Hall-effect transducer, a temperature-compensated comparator, a voltage regulator,
and a buffered high-side driver with an active pull-down. Supply
protection is made possible by the integration of overvoltage shutdown
circuitry that monitors supply fault conditions. Output protection
circuitry includes source and sink current current limiting for short
circuits to supply or ground.
The A3195E– is rated for operation over a temperature range of
-40°C to +85°C; the A3195L– is rated for operation over an extended
temperature range of -40°C to +150°C. They are supplied in a threelead SIP (suffix –U) or a surface-mount SOT-89 (suffix –LT).
FEATURES
■ Internal Protection For Automotive (ISO/DIN) Transients
■ Operation From Unregulated Supply
■ Reverse Battery Protection
■ Undervoltage Lockout
■ Supply Noise-Suppression Circuitry
■ Output Short-Circuit Protection
■ Output Zener Clamp
■ Thermal Protection
■ Symmetrical Latching Switch Points
■ Operable with Multipole Ring Magnets
*Fault condition, internal overvoltage shutdown
above 28 V.
Always order by complete part number, e.g., A3195LU .
3195
PROTECTED, HIGH-TEMP.,
ACTIVE PULL-DOWN
HALL-EFFECT LATCH
FUNCTIONAL BLOCK DIAGRAM
V
CC
OVERVOLT.
LOCKOUT
REG.
800
700
600
500
Dwg. FH-013
"U" PACKAGE
R
θJA
= 183°C/W
X
LATCH
OUTPUT
CURRENT
15kΩ
LIMIT
GROUND
TRANSFER CHARACTERISTICS
26 V
MAX
VOUT(H)
400
300
200
100
0
ALLOWABLE PACKAGE POWER DISSIPATION IN mW
"LT" PACKAGE
R
θJA
= 258°C/W
20
60 100 140 180
40 80 120
AMBIENT TEMPERATURE IN °C
160
Dwg. GH-054A
OUTPUT VOLTAGE IN VOLTS
0
-B
B
RP
0+B
FLUX DENSITY
B
OP
OUT(L)
V
Dwg. GH-034-3
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
W
Copyright © 1995, 1997, Allegro MicroSystems, Inc.
3195
PROTECTED, HIGH-TEMP.,
ACTIVE PULL-DOWN
HALL-EFFECT LATCH
ELECTRICAL CHARACTERISTICS
over operating voltage and temperature range (unless otherwise specified).
Limits
Characteristic Symbol Test Conditions Min. Typ. Max. Units
Supply Voltage V
Overvoltage Shutdown* V
Output Voltage, High V
(Source Voltage)
CC
CC(OV)
OUT(H)
Operating (but VCC x ICC VS TA limited) 3.8 12 26 V
B > B
B < B
OP
= -20 mA VCC -2 — VCC -0.3 V
RP, IOUT
28 — 55 V
Output Voltage, Low V
OUT(L)
(Sink Voltage) B > B
Output Clamp Voltage V
Output Current Limit I
Supply Current I
Reverse Battery Current* I
Output Rise Time t
Output Fall Time t
Package Thermal Resist. R
OUT(CLMP)
OUTMAX
CC
RCC
r
f
θJA
B > B
B < BRP, VCC > 26 V, I
<100 µA — 0.1 0.2 V
OP, IOUT
= 5 mA — 0.25 0.5 V
OP, IOUT
= 0 15 18 21 V
OUT
B < BRP, VCC = 12 V -26 — -70 mA
B > B
B < BRP, VCC = 18 V, I
B > B
V
V
V
, V
OP
OP
= +115 V* — 8.0 17 mA
CC
= -35 V* — -0.1 -5.0 mA
RCC
= -100 V* — -0.1 -10 mA
RCC
< 14 V 8.0 — 25 mA
OUT
= 0 — 6.0 9.0 mA
OUT
, VCC = 18 V, I
= 0 — 8.0 12 mA
OUT
CL = 20 pF, RL = 330 Ω — 0.12 2.0 µs
CL = 20 pF, RL = 330 Ω — 0.30 5.0 µs
“LT” Package — 258 — °C/W
“U” Package — 183 — °C/W
MAGNETIC CHARACTERISTICS
over operating voltage range (unless otherwise specified).
Limits
Characteristic Symbol Test Conditions Min. Typ. Max. Units
Operate Point B
Release Point B
Hysteresis B
(B
- BRP)T
OP
OP
RP
hys
TA = -40°C 60 125 200 G
T
= +25°C 50 110 160 G
A
T
= Maximum 40 100 150 G
A
TA = -40°C -200 -125 -60 G
T
= +25°C -160 -110 -50 G
A
T
= Maximum -150 -100 -40 G
A
TA = -40°C 150 250 — G
= +25°C 130 220 — G
A
T
= Maximum 110 200 — G
A
NOTES: Negative current is defined as coming out of (sourcing) the output.
BOP = magnetic operate point (output turns ON); BRP = magnetic release point (output turns OFF).
As used here, negative flux densities are defined as less than zero (algebraic convention).
Typical values are at TA = +25°C and VCC = 12 V.
* Fault condition. Device is shut down and operation is not possible.