ATS640JSB: True Zero-Speed, Self-Calibrating, Differential Hall-Effect Gear-Tooth Sensor IC For Two-Wire Applications

Data Sheet
27627.114a
ATS640JSB
TRUE ZERO-SPEED, SELF-CALIBRATING,
DIFFERENTIAL HALL-EFFECT GEAR-TOOTH SENSOR IC
FOR TWO-WIRE APPLICATIONS
4
3
2
The ATS640JSB Hall-effect gear-tooth sensor IC is a peak detecting device
that uses internal gain control to provide extremely stable duty cycles down to
zero speed. Each device consists of a high-temperature plastic shell
that holds together a samarium-cobalt pellet, a pole piece, and a true zerospeed BiCMOS differential Hall-effect gear-tooth sensor IC that has been
optimized to the magnetic circuit. This small package can be easily assembled
and used in conjunction with a wide variety of gear shapes and sizes.
1
Dwg. AH-006-3A
PRELIMINARY INFORMATION
I
T
N
O
ABSOLUTE MAXIMUM RATINGS
at TA = 25°C
L
P
Output OFF Voltage, VOUT ................... 26.5 V
Reverse Output Current, IROUT ............ 50 mA
I
D
E
R
H
S
6
S
AT
L
5
4
D
E
Y
B
continued next page…
C
A
Supply Voltage, VCC .......................... 26.5 V*
Reverse Supply Voltage, VRCC .............. -24 V
C
S
D
E
P
O
R
This device is ideal for use in gathering speed, position, and timing
information using gear-tooth-based configurations. The ATS640JSB is
particularly suited to those applications that require extremely accurate duty
cycle control or accurate edge detection. The lower vibration sensitivity also
makes this device extremely useful for transmission speed sensing.
U
N
(subject to change without notice)
August 28, 2002
U
D
The technology used for this device is Hall-effect based.
The chip incorporates a dual-element Hall IC that switches in
response to differential magnetic signals created by a ferrous target. The
sophisticated self-calibrating digital-processing circuitry normalizes the
internal gain of the device to minimize the effect of air gap variations. and to
reduce vibration sensitivity. The circuit eliminates magnet and system offsets
such as those caused by tilt yet provides zero-speed detection capabilities
without the associated running jitter inherent in classical digital solutions.
Pin 1 = Supply
Pin 2 = Current Output
Pin 3 = No Connection
Pin 4 = Ground
T
C
Package Power Dissipation,
PD .......................................... See Graph
Operating Temperature Range,
TA ................................ -40°C to +115°C*
Storage Temperature, TS .................. +170°C
Some restrictions may apply to certain types of sales.
Contact factory for details.
* Operation at increased supply voltages with
external circuitry is described in Applications
Information. Devices for operation at increased
temperatures are available on special order.
Always order by complete part number: ATS640JSB .
ATS640JSB
TRUE ZERO-SPEED,
TWO-WIRE
GEAR-TOOTH SENSOR IC
FEATURES AND BENEFITS
TYPICAL APPLICATION
Vcc
1
2
NC
X
3
SUPPLY
Icc + Io
0.1 µF
1V
–
+
-
Internal Current Regulator for 2-Wire Operation
True Zero-Speed Operation
Self Calibrating
Extremely Stable Duty Cycle with Temperature
Fully Optimized Differential Digital Gear-Tooth Sensor IC
Large Operating Air Gaps
Air-Gap Independent Switch Points
High Vibration Immunity
Single-Chip Sensing IC for High Reliability
Digital Output Representing Target Profile
Small Mechanical Size
Optimized Magnetic Circuit
<200 µs Typical Power-On Time
AGC and Reference-Adjust Circuit
Under-Voltage Lockout
Wide Operating Voltage Range
Defined Power-On State
X
+
4
100 Ω
Dwg. EH-011-1B
FUNCTIONAL BLOCK DIAGRAM
1 SUPPLY
UVLO
–
GAIN
X
E1
MAGNET
X
+
–
+
E2
3
INTERNAL
CONNECTION
CURRENT
OUTPUT
POWER-ON
LOGIC
–
OUTPUT
LOGIC
REG
2
REFERENCE
GENERATOR
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
+
4
GROUND
POSITIVE PEAK
ADC - DAC
TRACK & HOLD
NEGATIVE PEAK
ADC - DAC
TRACK & HOLD
Dwg. FH-019
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 2002 Allegro MicroSystems, Inc.
ATS640JSB
TRUE ZERO-SPEED,
TWO-WIRE
GEAR-TOOTH SENSOR IC
MECHANICAL INFORMATION
Component
Material
Package Face
Thermoset epoxy
Function
Units
170
°C*
Maximum temperature
Plastic Housing
Thermoplastic PBT
264 psi deflection temp. (DTUL)
66 psi deflection temp. (DTUL)
Approximate melting temperature
204°C
216°C
225°C
Flame Class Rating
—
—
UL94V-0
Leads
Copper
—
—
Lead Finish
90/10 tin/lead solder plate
—
†
Lead Pull
—
—
8N
*Temperature excursions to 225 °C for 2 minutes or less are permitted.
†All industry-accepted soldering techniques are permitted for these packages provided the indicated maximum temperature for each component (e.g., sensor face, plastic housing) is not exceeded. Reasonable dwell times, which do not
cause melting of the plastic housing, should be used.
Element Location (in millimeters)
(element location relative to package center is the design objective)
2.235
1.1
Lead Cross Section (in millimeters)
0.48
0.36
0.41
0.1
NOM.
0.38
A
NOM.
Dwg. MH-018 mm
www.allegromicro.com
0.44
0.35
0.0076
MIN. PLATING
THICKNESS
Dwg. MH-019A mm
ATS640JSB
TRUE ZERO-SPEED,
TWO-WIRE
GEAR-TOOTH SENSOR IC
DIMENSIONS IN MILLIMETERS
1.27
8.8
7.0
TYP
1
2
3
7.0
4
0.41
0.38
3.9
3.0 NOM
A
0.9 DIA
8.09
2.0
8.96
Dwg. MH-017-1B mm
Tolerances, unless otherwise specified: 1 place ±0.1 mm, 2 places ±0.05 mm.
The products described herein are manufactured under one or
more of the following U.S. patents: 5,045,920; 5,264,783; 5,442,283;
5,389,889; 5,581,179; 5,517,112; 5,619,137; 5,621,319; 5,650,719;
5,686,894; 5,694,038; 5,729,130; 5,917,320; and other patents
pending.
Allegro MicroSystems, Inc. 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 products are not authorized for use as critical components
in life-support appliances, devices, or systems without express written
approval.
The information included herein is believed to be accurate and
reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights
of third parties that may result from its use.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000