ATS660LSB
Data Sheet
27627.107
TRUE ZERO-SPEED, HALL-EFFECT
ADAPTIVE GEAR-TOOTH SENSOR
The ATS660LSB is an ideal gear-tooth sensor solution for uniform
teeth targets as found in today's demanding transmission applications.
This digital differential Hall-effect sensor is the choice when repeatabil-
ity and timing accuracy count. The ATS660LSB incorporates patented
self-calibration circuitry (U.S. Pat. 5,917,320) that nulls out the effects
of installation air gap, ambient temperature, and magnet offsets to
provide superior timing accuracy with symmetrical targets over large
operating air gaps -- typical of targets used in speed-sensing applica-
tions (pitches varying from below 0.5 to over 1.2 teeth per diametric
millimeter). The self-calibration at power up keeps the performance
optimized over the life of the sensor. The ATS660LSB has an open-
collector output for direct digital interfacing with no further signal
processing required. This device is available in a small 9-mm diameter
by 7-mm long package for optimal manufacturing.
The integrated circuit incorporates a dual-element Hall-effect
sensor and signal processing that switches in response to differential
magnetic signals created by the ferrous gear teeth. The circuitry
contains a sophisticated digital circuit to eliminate magnet and system
offsets and to achieve true zero-speed operation . D-to-A converters are
used to adjust the device gain at power on and to allow air-gap indepen-
dent switching, which greatly reduces vibration sensitivity of the
device.
FEATURES AND BENEFITS
I Fully optimized differential digital gear-tooth sensor
I Single-chip sensing IC for high reliability
I High vibration immunity
I Precise duty cycle
I Small mechanical size (9 mm diameter x 7 mm length)
I Automatic gain control circuitry (self calibration)
I True zero-speed operation
I Under-voltage lockout
I Wide operating temperature range
I Optimized Hall IC magnetic circuit
I Digital signal processing
I Large operating air gap range
I Wide operating voltage range
I Excellent repeatability performance
I Defined power-on state
Always order by complete part number: ATS660LSB .
Dwg. AH-006-4
1
2
3
4
Pin 1 = Supply
Pin 2 = Output
Pin 3 = Internal Connection
Pin 4 = Ground
ABSOLUTE MAXIMUM RATINGS
at T
A
= 25
C
Supply Voltage, V
CC
........................ 26.5 V*
Reverse Supply Voltage, V
RCC
............ -24 V
Output OFF Voltage, V
OUT
................. 26.5 V
Reverse Output Voltage, V
ROUT
.......... -24 V
Continuous Output Current, I
OUT
....... 20 mA
Reverse Output Current, I
ROUT
.......... 50 mA
Package Power Dissipation,
P
D
.......................................... See Graph
Operating Temperature Range,
T
A
............................. -40
C to +150
C*
Junction Temperature,
(continuous), T
J
.......................... +165
C
(100 hr), T
JM
............................... +180
C
Storage Temperature, T
S
................... +170
C
* Operation at increased supply voltages with
external circuitry is described in Applications
Information. Devices for operation at in-
creased temperatures are available on special
order.
PRELIMINARY INFORMATION
(subject to change without notice)
October 20, 2000
Some restrictions may apply to cer-
tain types of sales. Contact factory
for details.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
ATS660LSB
TRUE ZERO-SPEED,
HALL-EFFECT ADAPTIVE
GEAR-TOOTH SENSOR
2
Copyright 2000 Allegro MicroSystems, Inc.
FUNCTIONAL BLOCK DIAGRAM
SUPPLY
1
REG
UVLO
POWER-ON
LOGIC
+
REF
INTERNAL
CONNECTION
3
E2
MAGNET
E1
X
X
+
Dwg. FH-019-2A
OUTPUT
LOGIC
+
+
POSITIVE PEAK
DIGITAL PROC.
NEGATIVE PEAK
DIGITAL PROC.
32 V
THRESHOLD
COMPARATORS
GROUND
OUTPUT
<1
CURRENT
LIMIT
2
4
CONTROL
REFERENCE
GENERATOR
600
400
200
40
80
120
160
0
AMBIENT TEMPERATURE IN
C
ALLOWABLE PACKAGE POWER DISSIPATION IN mW
Dwg. GH-065-6
60
100
140
180
20
800
1000
R
JA
= 147
C/W
CO
NTINUO
US
100 HO
URS M
AX.
Pin 3 must be externally connected to pin 4.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
ATS660LSB
TRUE ZERO-SPEED,
HALL-EFFECT ADAPTIVE
GEAR-TOOTH SENSOR
4
OPERATION with reference gear at T
A
= +25
C.
Limits
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
Air-Gap Range
AG
Operational
0.5
2.5
mm
Calibration Cycle
n
cal
Output edges before which
1
1
1
Tooth
calibration is completed
Recalibration (Update)
n
rcal
Operating
646464Teeth
Minimum Speed
v
min
Teeth (cycles) per second
0
kHz
Maximum Speed
v
max
Teeth (cycles) per second
20
kHz
Duty Cycle Range
DC
1000 rpm, 0.5 mm < AG < 2.0 mm
5
%
REFERENCE GEAR DIMENSIONS
Limits
Characteristic
Symbol
Description
Min.
Typ.
Max.
Units
Diameter
D
O
120
mm
Tooth Width
T
3.0
mm
Valley Width
(p
C
T)
3.0
mm
Valley Depth
h
t
3.0
mm
Thickness
F
3.0
mm
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