ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
DYNAMIC, PEAK-DETECTING, DIFFERENTIAL
HALL-EFFECT GEAR-TOOTH SENSORS
1
2
3
4
Pin 1 = Supply
Pin 2 = Output
Pin 3 = Capacitor
Pin 4 = Ground
PRELIMINARY INFORMATION
(subject to change without notice)
December 2, 1998
ABSOLUTE MAXIMUM RATINGS
over operating temperature range
Supply Voltage, VCC.........................16 V*
Reverse Supply Voltage, V
Output OFF Voltage, V
Reverse Output Voltage, V
Continuous Output Current, I
Minimum External Capacitance,
............................................. 0.1 µF
C
3
Package Power Dissipation,
.................................... See Graph
P
D
Operating Temperature Range,
........................... -40°C to +150°C*
T
A
Storage Temperature, TS............ +170°C
* Operation at increased supply voltages with
external circuitry is described in Applications
Information. Devices for operation at increased
temperatures are available on special order.
RCC
................. 18 V
OUT
OUT
OUT
Dwg. AH-006
....... -0.5 V
....... -0.5 V
... 25 mA
ATS610LSA
AND
ATS611LSB
The ATS610LSA and ATS611LSB gear-tooth sensors are optimized Hall IC plus magnet subassemblies that provide a user-friendly
solution for digital gear-tooth sensing applications. Each subassembly
combines in a compact high-temperature plastic package, a samarium-cobalt
magnet, a pole piece, and a differential Hall-effect IC that has been
optimized to the magnetic circuit. These sensors can be easily used in
conjunction with a wide variety of gear or target shapes and sizes.
The ATS610LSA is designed to provide increased immunity to
false switching in applications that require the sensing of large-tooth
gears (e.g., crank angle or cam angle). The ATS611LSB is optimized
to sense fine-pitch gears over large working air gaps (e.g., transmission or ABS). These sensor subassemblies are ideal for use in
gathering speed, position, and timing information using gear-tooth-based
configurations.
The gear-sensing technology used for these sensor plus magnet
subassemblies is Hall-effect based. The sensor incorporates a
dual-element Hall IC that switches in response to differential magnetic
signals created by the ferrous target. The circuitry contains a patented
track-and-hold peak-detecting circuit to eliminate magnet and system
offset effects. This circuit has the ability to detect relatively fast changes,
such as those caused by gear wobble and eccentricities, and provides
stable operation at extremely low rotation speeds.
continued next page…
FEATURES AND BENEFITS
■ Fully Optimized Differential Digital Gear-Tooth Sensor
■ Single-Chip Sensing IC for High Reliability
■ Extremely Low Timing Accuracy Drift with Temperature
■ Large Operating Air Gaps
■ Small Mechanical Size
■ Optimized Magnetic Circuit
■ Patented Peak-Detecting Filter:
<200 µs Power-On Time
<10 RPM Operation (single-tooth target)
Correct First-Edge Detection
Uses Small Value Ceramic Capacitors
■ Under-Voltage Lockout
■ Wide Operating Voltage Range
■ Defined Power-Up State
Always order by complete part number, e.g., ATS610LSA .
Data Sheet
27627.100
ATS610LSA AND ATS611LSB
ALLOWABLE PACKAGE POWER DISSIPATION IN mW
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
Both sensors are packaged in miniature plastic
housings that have been optimized for size, ease of assembly,
and manufacturability. High operating temperature materials are used in all aspects of construction. Devices for
operation at increased temperatures are also available on
special order.
ATS610LSA: Large-tooth, gear-position sensing —
crank angle, cam angle.
ATS611LSB: Fine-pitch, large air gap, gear-speed
sensing — transmission, ABS.
1000
800
600
400
200
0
"SA" PACKAGE
θJA
= 147°C/W
R
"SB" PACKAGE
θJA
~ 150°C/W
R
60 100 140 18020
40 80 120
AMBIENT TEMPERATURE IN °C
160
Dwg. GH-065
1
REG
MAGNET
SUPPLY
X
X
FUNCTIONAL BLOCK DIAGRAM
POWER-ON
LOGIC
TRACK &
HOLD
3
CAPACITOR
E1
E2
UVLO
+
–
OUTPUT
2
+
–
4
GROUND
Dwg. FH-014
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
W
Copyright © 1997, Allegro MicroSystems, Inc.
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
ELECTRICAL CHARACTERISTICS over operating voltage and temperature range,
C
= 0.1 µF to 0.47 µF.
3
Limits
Characteristic Symbol Test Conditions Min. Typ. Max. Units
Supply Voltage V
CC
Power-On State POS V
Under-Voltage Lockout V
Under-Voltage Hysteresis V
Output Saturation Voltage V
Output Leakage Current I
Supply Current I
CC(UV)
CC(hys)
OUT(SAT)
OFF
CC
Operating, TJ < 165°CV
= 0 → 5 V HIGH HIGH HIGH –
CC
I
= 20 mA, VCC = 0 → 5 V 2.5 – 3.5 V
OUT
Lockout (V
I
= 20 mA – 90 400 mV
OUT
V
= 16 V – 0.2 15 µA
OUT
) – Shutdown – 0.1 – V
CC(UV)
Output OFF 5.5 7.7 11 mA
Output ON 8.5 10.5 13 mA
Power-On Delay t
Output Rise Time t
Output Fall Time t
NOTE: Typical data is at VCC = 5 V and TA = +25°C and is for design information only.
on
r
f
RL = 500 Ω, CL = 10 pF – 0.2 2.0 µs
RL = 500 Ω, CL = 10 pF – 0.2 2.0 µs
CC(UV)
– 16 V
––200 µs
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
ATS610LSA OPERATION over operating voltage and temperature range with reference target
(unless otherwise specified).
Limits
Characteristic Symbol Test Conditions Min. Typ. Max. Units
Air Gap Range AG Operating, 0.4 – 2.25 mm
Target Speed > 20 RPM
Minimum Air Gap AG
Maximum Air Gap AG
Timing Accuracy t
min
max
θ
Operating, One-Tooth (180°) – 0.25 – mm
Target, Target Speed = 1000 RPM
Operating, One-Tooth (180°) – 2.75 – mm
Target, Target Speed = 1000 RPM
Target Speed = 1000 RPM, – ±0.5 ±1.0 °
0.4 mm ≤ AG ≤ 2 mm
ATS611LSB OPERATION over operating voltage and temperature range with reference target
(unless otherwise specified).
Limits
Characteristic Symbol Test Conditions Min. Typ. Max. Units
Air Gap Range AG Operating, 0.4 – 2.5 mm
Target Speed > 20 RPM
Minimum Air Gap AG
min
Operating, One-Tooth (180°) – 0.75 – mm
Target*, Target Speed = 1000 RPM
Maximum Air Gap AG
Timing Accuracy t
max
θ
Operating, One-Tooth (180°) – 3.25 – mm
Target*, Target Speed = 1000 RPM
Target Speed = 1000 RPM, – ±0.5 ±1.0 °
0.4 mm ≤ AG ≤ 2 mm
* The one-tooth (180°) target is not recommended for use with the ATS611LSB.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
D = 115 mm
o
TARGET
F (THICKNESS) ≥ 3 mm
t
h = 5 mm
REFERENCE TARGET
3 mm
T = 3 mm
T = 180°
(ONE TOOTH)
E1 E2
SENSOR
POLE PIECE
SOUTH
PERMANENT
MAGNET
NORTH
1 2 3 4
TARGET
F (THICKNESS) ≥ 3 mm
E1 E2
SENSOR
POLE PIECE
SOUTH
D = 115 mm
o
AIR GAP
AIR GAP
t
h = 5 mm
Dwg. MH-016 mm
ONE-TOOTH (180
°) TARGET
PERMANENT
MAGNET
NORTH
1 2 3 4
Dwg. MH-016-1 mm
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
TYPICAL ATS610LSA AND ATS611LSB ELECTRICAL CHARACTERISTICS
14
12
11
10
9.0
8.0
7.0
SUPPLY CURRENT IN mA
6.0
4.0
-40
0 40 80 120
AMBIENT TEMPERATURE IN °C
OUTPUT ON
V = 5 V
CC
OUTPUT OFF
160
200
Dwg. GH-014-1
13
12
11
10
9.0
8.0
7.0
SUPPLY CURRENT IN mA
6.0
5.0
OUTPUT ON
OUTPUT OFF
T = 25°C
A
2.0 6.0 10 14 18
SUPPLY VOLTAGE IN VOLTS
Dwg. GH-058
150
125
100
75
I = 20 mA
OUT
OUTPUT SATURATION VOLTAGE IN mV
50
-40
0 40 80 120
AMBIENT TEMPERATURE IN °C
175
150
125
100
75
50
25
OUTPUT SATURATION VOLTAGE IN mV
160
200
0
0
10 20 30
OUTPUT SINK CURRENT IN mA
Dwg. GH-013-1
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
T = 25°C
A
40
Dwg. GH-059
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
TYPICAL ATS610LSA OPERATING CHARACTERISTICS
(with reference target)
3.0
TRAILING TARGET EDGE
2.5
2.0
1.5
1.0
0.5
RELATIVE ACCURACY IN DEGREES
0
-40°C
+25°C
+150°C
0.5 1.5 2.5 3.5
1.0 2.0 3.00
AIR GAP IN MILLIMETERS
Dwg. GH-008
3.0
LEADING TARGET EDGE
2.5
2.0
1.5
1.0
0.5
RELATIVE ACCURACY IN DEGREES
0
-40°C
+25°C
+150°C
0.5 1.5 2.5
1.0 2.0 3.00
AIR GAP IN MILLIMETERS
3.5
Dwg. GH-008-2
53.0
52.8
52.6
52.4
52.2
52.0
51.8
DUTY CYCLE IN PER CENT
51.6
51.4
-40°C
+25°C
+150°C
0.5 1.5 2.5 3.5
1.0 2.0 3.00
AIR GAP IN MILLIMETERS
Dwg. GH-008-1
continued next page…
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
TYPICAL ATS610LSA OPERATING CHARACTERISTICS
(with reference target) — Continued
4.5
4.0
3.5
3.0
2.5
2.0
1.5
MAXIMUM AIR GAP IN MILLIMETERS
1.0
0
10 30 50 70
20 40 60
REFERENCE TARGET SPEED IN RPM
TYPICAL ATS611LSB OPERATING CHARACTERISTICS
-40°C
+25°C
+150°C
4.5
4.0
3.5
3.0
2.5
2.0
1.5
MAXIMUM AIR GAP IN MILLIMETERS
1.0
0
Dwg. GH-011-1
(with reference target)
-40°C
+25°C
+150°C
500 1500 2500 3500
1000 2000 3000
REFERENCE TARGET SPEED IN RPM
Dwg. GH-011
4.5
4.0
3.5
3.0
2.5
2.0
1.5
MAXIMUM AIR GAP IN MILLIMETERS
1.0
0
500 1500 2500 3500
1000 2000 3000
REFERENCE TARGET SPEED IN RPM
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
-40°C
+25°C
+150°C
Dwg. GH-011-2
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
DEVICE DESCRIPTION
The ATS610LSA and ATS611LSB dynamic,
peak-detecting, differential Hall-effect gear-tooth sensors
are Hall IC plus magnet subassemblies that are fully
optimized to provide digital detection of gear-tooth edges
in a small package size. Both sensors are packaged in
identical miniature plastic housings that have been
optimized for size, ease of assembly, and manufacturability.
High operating temperature materials are used in all
aspects of construction.
The application of these sensors is uncomplicated.
After power is applied to the device, they are capable of
quickly providing digital information that is representative
of a rotating gear or specially designed target. No additional optimization or processing circuitry is required. This
ease of use should reduce design time and incremental
assembly costs for most applications.
Sensing Technology. Both gear-tooth sensor subassemblies contain a single-chip differential Hall-effect
sensor IC, a samarium-cobalt magnet, and a flat ferrous
pole piece. The Hall IC consists of two Hall elements
spaced 2.235 mm (0.088") apart, which sense the magnetic gradient created by the passing of a ferrous object (a
gear tooth). The two Hall voltages are compared and the
difference is then processed to provide a digital output
signal.
The processing circuit uses a patented peak-detection
technique to eliminate magnet and system offsets. This
technique allows coupling and filtering of offsets without
the power-up and settling time disadvantages of classical
high-pass filtering schemes. Here, the peak signal of
every tooth and valley is detected and is used to provide
an instant reference for the operate-point and releasepoint comparators. In this manner, the thresholds are
adapted and referenced to individual signal peaks and
valleys, thereby providing immunity to zero-line variation
due to installation inaccuracies (tilt, rotation, and
off-center placement), as well as for variations caused by
target and shaft eccentricities. The peak detection
concept also allows extremely low-speed operation when
used with small-value capacitors.
OPERATE
0
DIFFERENTIAL
MAGNETIC FLUX
V
BB
OUTPUT
V
OUT(SAT)
RELEASE
OPERATE
RELEASE
Dwg. WH-011
Power-On Operation. The device will power on in the
OFF state (output high) irrespective of the magnetic field
condition. The power-on time of the circuit is no greater
than 200 µs. The circuit is then ready to accurately detect
the first target edge that results in a HIGH-to-LOW transition.
Under-Voltage Lockout. When the supply voltage is
below the minimum operating voltage (V
CC(UV)
), the device
is OFF and stays OFF irrespective of the state of the
magnetic field. This prevents false signals, which may be
caused by under-voltage conditions (especially during turn
on), from appearing at the output.
Output. The device output is an open-collector stage
capable of sinking 25mA. An external pull-up (resistor) to
a supply voltage of not more than 18V must be supplied.
Superior Performance. The ATS610LSA and
ATS611LSB peak-detecting differential gear-tooth sensor
sub-assemblies have several advantages over conventional Hall-effect gear-tooth sensors.
continued next page…
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
DEVICE DESCRIPTION — Continued
Differential vs. Single-Element Sensing. The differential Hall-element configuration is superior in most applications to the classical single-element gear-tooth sensor.
The single-element configuration commonly used
(Hall-effect sensor mounted on the face of a simple
permanent magnet) requires the detection of a small
signal (often <100G) that is superimposed on a large
back-biased field, often 1500G to 3500G. For most
gear/target configurations, the back-biased field values
change due to concentration effects, resulting in a varying
baseline with air gap, with valley widths, with eccentricities, and with vibration. The differential configuration
cancels the effects of the back-biased field and avoids
many of the issues presented by the single Hall element.
NOTE — 10 G = 1 mT, exactly.
Peak-Detecting vs. AC-Coupled Filters. High-pass
filtering (normal ac coupling) is a commonly used technique for eliminating circuit offsets. AC coupling has
errors at power up because the filter circuit needs to hold
the circuit zero value even though the circuit may power
up over a large signal. Such filter techniques can only
perform properly after the filter has been allowed to settle,
which is typically greater than one second. Also, highpass filter solutions cannot easily track rapidly changing
baselines such as those caused by eccentricities. Peak
detection switches on the change in slope of the signal
and is baseline independent at power up and during
running.
Track-and-Hold Peak Detecting vs. Zero-Crossing
Reference. The usual differential zero-crossing sensors
are susceptible to false switching due to off-center and
tilted installations, which result in a shift in baseline that
changes with air gap. The track-and-hold peak-detection
technique ignores baseline shifts versus air gaps and
provides increased immunity to false switching. In addition, using track-and-hold peak-detecting techniques,
increased air gap capabilities can be expected because a
peak detector utilizes the entire peak-to-peak signal range
as compared to zero-crossing detectors that switch on
fixed thresholds.
NOTE — “Baseline” refers to the zero-gauss differential where each Hall-effect element is subject to the
same magnetic field strength.
TARGET
-2000
-2500
-3000
-3500
-4000
-4500
SINGLE ELEMENT MAGNETIC FIELD IN GAUSS
-5000
0
10 20 30 60
ANGLE OF TARGET ROTATION IN DEGREES
AIR GAP = 0.5 mm
AIR GAP = 1.0 mm
AIR GAP = 1.5 mm
AIR GAP = 2.0 mm
AIR GAP = 2.5 mm
showing the impact of varying valley widths
T = 25°C
A
5040
Dwg. GH-061-1
1500
1000
500
0
-500
-1000
DIFFERENTIAL MAGNETIC FIELD IN GAUSS
-1500
0
AIR GAP = 0.5 mm
AIR GAP = 1.0 mm
AIR GAP = 2.5 mm
AIR GAP = 2.0 mm
AIR GAP = 1.5 mm
10 20 30 60
ANGLE OF TARGET ROTATION IN DEGREES
Differential flux maps vs. air gapsSingle-element flux maps
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
TARGET
T = 25°C
A
5040
Dwg. GH-061
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
CRITERIA FOR DEVICE QUALIFICATION
All Allegro sensors are subjected to stringent qualification requirements prior to being released to production.
To become qualified, except for the destructive ESD tests, no failures are permitted.
Qualification Test Test Method and Test Conditions Test Length Samples Comments
Temperature Humidity JESD22-A101, 1000 hrs 48 Device biased for
Bias Life TA = 85°C, RH = 85% minimum power
Bias Life JESD22-A108, 1000 hrs 48
TA = 150°C, TJ = 165°C
(Surge Operating Life) JESD22-A108, 168 hrs 24
TA = 175°C, TJ = 190°C
Autoclave, Unbiased JESD22-A102, 96 hrs 48
TA = 121°C, 15 psig
High-Temperature JESD22-A103, 1000 hrs 48
(Bake) Storage Life TA = 170°C
Temperature Cycle JESD22-A104 1000 cycles 60
ESD, CDF-AEC-Q100-002 Pre/Post 3 per Test to failure
Human Body Model Reading test All leads > 3 kV
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
APPLICATIONS INFORMATION
Gear Diameter and Pitch. Signal frequency is a direct
function of gear pitch and rotational speed (RPM). The
width of the magnetic signal in degrees and, hence, the
signal slope created by the tooth is directly proportional to
the circumference of the gear (πDo). Smaller diameters
limit the low-speed operation due to the slower rate of
change of the magnetic signal per degree of gear rotation
(here the limitation is the droop of the capacitor versus the
signal change). Larger diameters limit high-speed operation due to the higher rate of change of magnetic signal
per degree of rotation (here the limitation is the maximum
charge rate of the capacitor versus the rate of signal
change). These devices are optimized for a 50mm gear
diameter (signal not limited by tooth width), 0.33 µF
capacitor, and speeds of 10 RPM to 8000 RPM. For very
large diameter gears (diameter >200 mm), the devices
must be configured with a lower value capacitor, but not
less than 0.1 µF. This allows for a range of 5:1 in gear
diameters.
NOTE — In application, the terms “gear” and “target” are
often interchanged. However, “gear” is preferred when
motion is transferred.
Air Gap and Tooth Geometry. Operating specifications
are impacted by tooth width (T), valley width (pc - T) and
depth (ht), gear material, and gear face thickness (F). The
target can be a gear or a specially cut shaft-mounted tone
wheel made of stamped ferrous metal. In general, the
following gear or target guidelines must be followed to
achieve greater than 2mm air gap from the face of unit:
Tooth width, T.............................. >2 mm
Valley width, pc - T...................... >2 mm
(Whole) depth, ht......................... >3 mm
Gear material............................... low-carbon steel
Gear face width (thickness), F .... >3 mm
Deviation from these guidelines will result in a reduction of air gap and a deterioration in timing accuracy. For
applications that require the sensing of large-tooth targets,
the optimal sensor choice is the ATS610LSA. Here, the
higher switching thresholds provide increased immunity to
false switching caused by magnetic overshoot and other
non-uniformities in the gear or target. For applications
that require the sensing of a target with a repetitive target
structure (valley width less than 5mm), the optimal sensor
choice is the ATS611LSB. Here, the lower switching
thresholds make the device more sensitive to magnetic
field changes and will provide larger operating air gaps.
Operation with Fine-Pitch Gears. For targets with a
circular pitch of less than 4mm, a performance improvement can be observed by rotating the front face of the
sensor subassembly. This sensor rotation decreases the
effective sensor-to-sensor spacing and increases the
capability of detecting fine tooth or valley configurations,
provided that the Hall elements are not rotated beyond the
width of the target.
2.235
TARGET FACE WIDTH, F
>2.235 SIN
α
α
α
2.235 COS
A
A
Dwg. MH-018-1 mm
Signal Timing Accuracy. The magnetic field profile
width is defined by the sensor element spacing and
narrows in degrees as the target diameter increases. This
results in improved timing accuracy performance for larger
gear diameters (for the same number of gear teeth). The
slope of this magnetic profile also changes with air gap,
resulting in timing accuracy shift with air gap (refer to
typical operating characteristic curves). Valley-to-tooth
transitions will generally provide better accuracy than
tooth-to-valley transitions for large-tooth or large-valley
configurations. For highest accuracy, targets greater than
100mm in diameter should be used.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
continued next page…
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
APPLICATIONS INFORMATION — Continued
Signal Duty Cycle. For repetitive target structures,
precise duty cycle is maintained over the operating air gap
and temperature range due to an extremely good symmetry in the magnetic switch points of the device. For
nonrepetitive target structures, there will be a small but
measureable change in pulse width versus air gap.
Output Polarity. The output of the device will switch from
HIGH to LOW as the leading edge of the target passes
the subassembly in the direction indicated below (pin 4 to
pin 1), which means that the output will be LOW when the
unit is facing a tooth. If rotation is in the opposite direction
(pin 1 to pin 4), the output of the device will switch from
LOW to HIGH as the leading edge of the target passes
the subassembly, which means that the output will be
HIGH when the unit is facing a tooth.
1
2
3
4
4
3
2
1
Dwg. AH-007
Operation From a Regulated Power Supply. These
devices require minimal protection circuitry during operation from a low-voltage regulated line. The on-chip
voltage regulator provides immunity to power supply
variations between 3.5V and 16V. However, even while
operating from a regulated line, some supply and output
filtering is required to provide immunity to coupled and
injected noise on the supply line. A basic RC low-pass
circuit (R1C1) on the supply line and an optional output
capacitor (C2) is recommended for operation in noisy
environments. Because the device has an open-collector
output, an output pull-up resistor (RL) must be included
either at the sensor output (pin 2) or by the signal processor input.
Dwg. AH-006-1
Power Supply Protection. The sensor contains an onchip voltage regulator and can operate over a wide supply
voltage range. For devices that need to operate from an
unregulated power supply, transient and double-battery
protection should be added externally. For applications
using a regulated supply, external EMI/RFI protection is
often required. Insufficient protection can result in unexplained pulses on the output line, providing inaccurate
sensing information to the user.
The filter capacitor and EMI protection circuitry can
easily be added to a PC board for use with these devices.
Provisions have been made for simple mounting of a
board on the back of the unit.
SUPPLY
20 Ω
OUTPUT
C
R
L
C
R
1
0.033 µF
1
12
Vcc
X
2
100 pF
0.22 µF
C
3
4
3
+
-
X
continued next page…
Dwg. EH-008-1A
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
APPLICATIONS INFORMATION — Continued
Operation From an Unregulated Power Supply. In
automotive applications, where the device receives its
power from an unregulated supply such as the battery, full
protection is generally required so that the device can
withstand the many supply-side transients. Specifications
for such transients vary between car manufacturers, and
protection-circuit design should be optimized for each
application. In the circuit below, a simple
Zener-controlled regulator is constructed using discrete
components. The RC low-pass filter on the supply line
(R1C1) and a low-value supply bypass capacitor (CS) can
be included, if necessary, so as to minimize susceptibility
to EMI/RFI. The npn transistor should be chosen with
sufficiently high forward breakdown voltage so as to
withstand supply-side transients. The series diode should
be chosen with sufficiently high reverse breakdown
capabilities so as to withstand the most negative transient. The current-limiting resistor (RZ) and the Zener
diode should be sized for power dissipation requirements.
SUPPLY
R
L
OUTPUT
C
2
100 pF
Capacitor Requirements. The choice of the capacitor at
pin 3 (C3) defines the minimum operating speed of the
target. This capacitor (0.1 µF minimum) is required to
stabilize the internal amplifiers as well as to eliminate the
signal offsets. Typically, a 0.33 µF low-leakage ceramic
capacitor is recommended. Values greater than 0.47 µF
should not be used as this may cause high-speed performance degradation.
Capacitor leakage current at pin 3 will cause degradation in the low-speed performance of the device. Excess
capacitor leakage can result in the sensor changing output
state without movement of the gear tooth being sensed.
In addition to the capacitor leakage, it is extremely important to minimize the leakage at the PC board and between
the pins of the sensor. Up to 50nA of external leakage
can be tolerated at the capacitor pin node to ground.
Choice of low-leakage-current potting compounds and the
use of clean PC board techniques are extremely important.
0.033 µF
C
2.5 kΩ
R
S
20 Ω
R
1
Z
6.8 V
C
1
0.033 µF
12
Vcc
0.22 µF
3
C
3
4
Additional applications Information on gear-tooth and
other Hall-effect sensors is provided in the Allegro Electronic Data Book AMS-702 or Application Note 27701.
+
-
X
X
Dwg. EH-008A
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
MECHANICAL INFORMATION
Component Material Function Units
Sensor Face Thermoset epoxy Maximum temperature 170°C*
Plastic Housing Thermoplastic PBT, 264 psi deflection temp. (DTUL) 204°C
30% glass filled 66 psi deflection temp. (DTUL) 216°C
Approximate melting temperature 225°C
Leads Copper ––
Lead Pull –– 8 N
Lead Finish 90/10 tin/lead solder plate –†
Flame Class Rating –– UL94V-0
*Temperature excursions to 225 °C for 2 minutes or less are permitted.
†All industry-accepted soldering techniques are permitted for these subassemblies 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.
Sensor Location (in millimeters)
(sensor location relative to package center is the design
objective)
2.235
1.1
0.1
Lead Cross-Section (in millimeters)
0.41
0.38
A
Dwg. MH-018 mm
0.0076
MIN. PLATING
THICKNESS
Dwg. MH-019 mm
continued next page…
ATS610LSA AND ATS611LSB
DYNAMIC, PEAK-DETECTING,
DIFFERENTIAL HALL-EFFECT
GEAR-TOOTH SENSORS
ATS610LSA DIMENSIONS IN MILLIMETERS
3.0
NOM
0.38
0.38
1.27
TYP
1 2 3 4
8.3
8.0
SEE NOTE
1.27
TYP
1 2 3 4
0.41
0.9
7.25
5.00
DIA
2.0
9.0
3.9
ATS611LSB DIMENSIONS IN MILLIMETERS
0.41
8.8
7.0
7.0
A
9.0
Dwg. MH-017A mm
3.0
NOM
0.9
DIA
3.9
A
2.0
Tolerances unless otherwise specified:1 place ±0.1 mm, 2 places ±0.05 mm.
NOTE — Nominal dimension and tolerances dependent on package material. Contact factory.
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 design of its products.
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 which may result from its use.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
8.968.09
Dwg. MH-017-1B mm
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