ATS645 Datasheet

ATS645LSH
Two-Wire True Zero Speed Miniature Differential
Peak-Detecting Gear Tooth Sensor IC
Not for New Design
These parts are in production but have been determined to be
NOT FOR NEW DESIGN. This classification indicates that sale of
this device is currently restricted to existing customer applications.
The device should not be purchased for new design applications
because obsolescence in the near future is probable. Samples are no
longer available.
Date of status change: January 2, 2009
Recommended Substitutions:
NOTE: For detailed information on purchasing options, contact your
local Allegro field applications engineer or sales representative.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, revisions to the anticipated product life cycle plan
for a product to accommodate changes in production capabilities, alternative product availabilities, or market demand. 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.
ATS645LSH
Two-Wire True Zero Speed Miniature Differential
Peak-Detecting Gear Tooth Sensor IC
Features and Benefits
Description
•
•
•
•
•
•
•
•
•
•
The components in speed sensing applications continue to
diminish in size to meet spatial constraints and weight reduction
requirements. As the geometries of gears become smaller, this
can compromise the capabilities of a gear speed sensor. The
ATS645 Hall-element-to-Hall-element spacing of only 1.5 mm
makes this device uniquely capable of accommodating very
fine-pitch gears. In addition, the ATS645 signal peak-detecting
algorithm supports consistent switching at relatively large air
gaps, where the peak-to-peak amplitude is small. These features
make the ATS645 the ideal solution to detect the speed of finepitch targets such as those found in ABS (antilock braking)
systems.
Fully optimized differential digital gear tooth sensor IC
Single chip IC for high reliability
Internal current regulator for 2-wire operation
Small mechanical size (8 mm diameter x 5.5 mm depth)
Air gap independent switchpoints
Digital output representing gear profile
Precise duty cycle signal over operating temperature range
Large operating air gaps
Automatic Gain Control (AGC)
Automatic Offset Adjustment (AOA)
Continued on the next page…
The ATS645 combines a Hall-effect sensing integrated circuit
and rare earth pellet to provide a manufacturer-friendly solution
for true zero-speed digital gear-tooth sensing in two-wire
applications. The device consists of a single-shot molded
plastic package that includes a samarium cobalt pellet, a
pole piece, and a Hall-effect integrated circuit 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.
Packages: 4 pin SIP (suffix SH)
Continued on the next page…
Not to scale
Functional Block Diagram
Hall
Amplifier
Automatic Offset
Control
Tracking
DAC
VCC
Gain
AOA DAC
AGC DAC
Internal Regulator
Peak Hold
GND
Test Signals
ATS645-DS, Rev. 6
Test
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
Features and Benefits (continued)
• True zero-speed operation
• Undervoltage lockout
• Wide operating voltage range
• Defined power-on state
Description (continued)
The integrated circuit incorporates a dual-element Hall effect circuit
as well as signal processing that switches the output state in response
to changes in the magnetic gradients created by ferromagnetic
gear teeth. The circuitry contains a sophisticated digital circuit to
eliminate magnet and system offsets and to achieve true zero speed
operation (U.S. Patent 5,917,320). A-D and D-A converters are
used to adjust the device gain at power-on and to allow switching
independent of the breadth of the air gap.
The regulated current output is configured for two wire applications,
requiring one less wire for operation than do switches with the more
traditional open-collector output. The package is available in a lead
(Pb) free version, with 100% matte tin leadframe plating.
Part Number
Packing*
ICC Typical
ATS645LSHTN-I1-T
Tape and Reel 13-in. 800 pcs./reel
6.0 Low to 14.0 High mA
ATS645LSHTN-I2-T
Tape and Reel 13-in. 800 pcs./reel
7.0 Low to 14.0 High mA
*Contact Allegro
for additional packing options. Some restrictions may apply to certain types of sales. Contact
Allegro for details.
Absolute Maximum Ratings
Characteristic
Symbol
Supply Voltage
VCC
Reverse-Supply Voltage
VRCC
–
V
ºC
TJ(max)
165
ºC
Tstg
–65 to 170
ºC
Maximum Junction Temperature
Range L
Terminal List
Name
VCC
NC
1 2 3 4
Units
28
–18
TA
Pin-out Diagram
Rating
–40 to 150
Operating Ambient Temperature
Storage Temperature
Notes
Description
Number
Connects power supply to chip
1
No connection
2
TEST
For Allegro use, float or tie to GND
3
GND
Ground terminal
4
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
OPERATING CHARACTERISTICS using reference target 60-0, TA and VCC within specification, unless otherwise noted
CHARACTERISTIC
Min.
Typ.1
Max.
Units
4.0
–
24
V
VCC 0 → 5 V and 5 → 0 V
–
–
4.0
V
Symbol
Test Conditions
ELECTRICAL CHARACTERISTICS
Supply Voltage2
Undervoltage Lockout
VCC
VCC(UV)
Operating; TJ < 165 °C
Supply Zener Clamp Voltage
VZ
ICC = ICC(max) + 3 mA; TA = 25°C
28
–
–
V
Supply Zener Current
IZ
Test conditions only; VZ = 28 V
–
–
ICC(max)+
3 mA
mA
ATS645LSH-I1
4.0
6
8.0
mA
ATS645LSH-I2
5.9
7
8.4
mA
ATS645LSH-I1
12.0
14.0
16.0
mA
ATS645LSH-I2
11.8
14.0
16.8
mA
1.85
–
3.05
–
t > tPO
–
ICC(High)
–
–
ICC(Low)
Supply Current
ICC(High)
Supply Current Ratio
ICC(High)/ Ratio of high current to low current
ICC(Low)
POWER-ON STATE CHARACTERISTICS
Power-On State
POS
Power-On Time3
tPO
Target gear speed < 100 rpm
–
1
2
ms
dI/dt
RLOAD = 100 Ω, CLOAD = 10 pF
–
10
–
mA/μs
OUTPUT STAGE
Output Slew Rate4
Continued on the next page.
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
OPERATING CHARACTERISTICS (continued) using reference target 60-0, TA and VCC within specification, unless otherwise noted
Characteristic
Symbol
Min.
Typ.1
Max.
Units
Reference Target 60-0
0
–
8,000
rpm
Equivalent to f – 3dB
20
40
–
kHz
–
120
–
mV
–
120
–
mV
–
–
3
Edge
Output switching only; may not meet datasheet specifications
–60
–
60
G
∆DC within specification
0.5
–
2.75
mm
–
–
3
mm
43
53
63
%
Operating within specification
30
–
1000
G
Output switching (no missed edges); ∆DC not
guaranteed
20
–
–
G
Test Conditions
SWITCHPOINT CHARACTERISTICS
Rotation Speed
SROT
Analog Signal Bandwidth
BW
Operate Point
BOP
Release Point
BRP
Transitioning from ICC(High) to ICC(Low); positive peak
referenced; AG < AGMAX
Transitioning from ICC(Low) to ICC(High); negative peak
referenced; AG < AGMAX
CALIBRATION
Initial Calibration
CI
Quantity of rising output (current) edges required for
accurate edge detection
DAC CHARACTERISTICS
Allowable User-Induced Differential
Offset
FUNCTIONAL CHARACTERISTICS5
Operational Air Gap Range6
Maximum Operational Air Gap
Range
Duty Cycle Variation7
Operating Magnetic Flux Density
Differential8
Minimum Operating Signal
AG
AGOP(max)
∆DC
BAG(p-p)
SigOP(min)
Output switching (no missed edges); ∆DC not
guaranteed
Wobble < 0.5mm; Typical value at AG = 1.5 mm, for
max., min., AG within specification
1Typical
values are at TA = 25°C and VCC = 12 V. Performance may vary for individual units, within the specified maximum and minimum limits.
voltage must be adjusted for power dissipation and junction temperature; see Power Derating section.
3Power-On Time includes the time required to complete the internal automatic offset adjust. The DACs are then ready for peak acquisition.
4dI is the difference between 10% of I
CC(Low) and 90% of ICC(High), and dt is time period between those two points.
Note: di/dt is dependent upon the value of the bypass capacitor, if one is used.
5Functional characteristics valid only if magnetic offset is within the specified range for Allowable User Induced Differential Offset.
6AG is dependent on the available magnetic field. The available field is dependent on target geometry and material, and should be independently
characterized. The field available from the reference target is given in the reference target parameter section of the datasheet.
7Duty cycle specification may not be met if the magnetic signal during the calibration period is not representative of the installation air gap.
8In order to remain in specification, the magnetic gradient must induce an operating signal greater than the minimum value specified. This includes the
effect of target wobble.
2Maximum
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
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4
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
REFERENCE TARGET, 60-0 (60 Tooth Target)
Characteristics
Symbol
Test Conditions
Typ.
Units
120
mm
Outside Diameter
Do
Outside diameter of target
Face Width
F
Breadth of tooth, with respect to
branded face
6
mm
Circular Tooth Length
t
Length of tooth, with respect to
branded face; measured at Do
3
mm
Circular Valley Length
tv
Length of valley, with respect to
branded face; measured at Do
3
mm
Tooth Whole Depth
ht
3
mm
–
–
Material
Low Carbon Steel
Symbol Key
of Package
Reference Gear Magnetic Gradient Amplitude
With Reference to Air Gap
800
600
500
400
300
200
Branded Face
of Package
100
0
0.5
1
1.5
2
2.5
Reference Target
60-0
3
Air Gap (mm)
Reference Gear Magnetic Profile
Two Tooth-to-Valley Transitions
500
Air Gap
400
(mm)
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
300
Differential B* (G)
Peak-to-Peak Differential B (G)
700
200
100
0
-100
-200
3.00 mm AG
-300
0.50 mm AG
-400
-500
0
2
4
6
8
10
12
Gear Rotation (°)
*Differential B corresponds to the calculated difference in the magnetic field as
sensed simultaneously at the two Hall elements in the device (BDIFF = BE1 – BE2).
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115 Northeast Cutoff
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True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
Characteristic Data
I1 Trim
Duty Cycle vs. Air Gap
100 RPM, VCC = 12 V
65
TA, (ºC)
-40
25
150
60
TA, (ºC)
-40
25
150
60
55
Duty Cycle (%)
55
Duty Cycle (%)
Duty Cycle vs. Target Speed
Air Gap 1.5 mm, VCC = 12 V
65
50
45
40
50
45
40
35
35
0
0.5
1
1.5
2
2.5
3
3.5
0
200
400
600
Air Gap (mm)
Duty Cycle vs. Air Gap
1000 RPM, VCC = 12 V
65
800
1000
1200
1400
1600
Target Speed (RPM)
Supply Current vs. Supply Voltage
18
60
ICC(High)
15
12
ICC (mA)
Duty Cycle (%)
55
50
45
9
ICC(Low)
6
TA, (ºC)
-40
25
150
40
35
0
0.5
1
1.5
2
Air Gap (mm)
2.5
3
TA, (ºC)
-40
25
150
3
3.5
0
0
5
10
15
20
25
30
VCC (V)
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True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
THERMAL CHARACTERISTICS may require derating at maximum conditions, see application information
CHARACTERISTIC
Symbol
TEST CONDITIONS*
RθJA
Package Thermal Resistance
Value
Units
Single-layer PCB with copper limited to solder pads
126
ºC/W
Two-layer PCB with 3.8 in.2 of copper area on each side connected with thermal vias and to device ground pin
84
ºC/W
Maximum Allowable VCC (V)
*Additional information is available on the Allegro Web site.
Power Derating Curve
TJ(max) = 165ºC; ICC = ICC(max)
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
VCC(max)
(RθJA = 84 ºC/W)
(RθJA = 126 ºC/W)
VCC(min)
20
40
60
80
100
120
140
160
180
Power Dissipation, PD (m W)
Temperature (ºC)
Maximum Power Dissipation, PD(max)
TJ(max) = 165ºC; VCC = VCC(max); ICC = ICC(max)
1900
1800
1700
1600
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
(R
θJ
(R
θJ
20
40
60
A
=1
26
ºC
A
=
/W
84
ºC
/W
)
)
80
100
120
Temperature (°C)
140
160
180
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
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True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
Functional Description
Hall Technology
Output Polarity
The gear tooth sensor IC subassembly contains a single-chip
differential Hall effect sensor IC, an optimized samarium cobalt
pellet, and a flat ferrous pole piece. The Hall IC supports two
Hall elements, which sense the magnetic profile of the ferromagnetic target simultaneously, but at different points (spaced at a
1.5 mm pitch), generating a differential internal analog voltage
(VPROC) that is processed for precise switching of the digital
output signal.
Figure 3 shows the output polarity for the orientation of target
and package shown in figure 2. The target direction of rotation shown is: perpendicular to the leads, across the face of the
device, from the pin 1 side to the pin 4 side. This results in the
IC output switching from high, ICC(High), to low ICC(Low), as the
leading edge of a tooth (a rising mechanical edge, as detected by
the IC) passes the package face. In this configuration, the device
output current switches to its low polarity when a tooth is the
target feature nearest to the package. If the direction of rotation
is reversed, then the output polarity inverts.
The Hall IC is self-calibrating and also possesses a temperature compensated amplifier and offset cancellation circuitry. Its
voltage regulator provides supply noise rejection throughout the
operating voltage range. Changes in temperature do not greatly
affect this device due to the stable amplifier design and the offset
rejection circuitry. The Hall transducers and signal processing
electronics are integrated on the same silicon substrate, using a
proprietary BiCMOS process.
Target Profiling
An operating device is capable of providing digital information
that is representative of the mechanical features on a rotating
target. The waveform diagram shown in figure 3 presents the
automatic translation of the mechanical profile, through the magnetic profile that it induces, to the digital output signal of the IC.
Note that output voltage polarity is dependent on the position of
the sense resistor, RSENSE (see figure 4).
Target
Mechanical Profile
Representative
Differential
Magnetic Profile
IC Electrical
Output Profile, IOUT
Figure 3. Output Profile of a ferrous target for the polarity indicated in
figure 2.
VCC
VCC
Target (Gear)
RSENSE
Element Pitch
Hall Element 2
Dual-Element
Hall Effect Device
ICC
VOUT(H)
Hall Element 1
Hall IC
Pole Piece
(Concentrator)
Back-biasing
Rare-earth Pellet
South Pole
North Pole
Case
(Pin 4 Side)
(Pin 1 Side)
1
1
VCC
VCC
ATS645
ATS645
GND
4
GND
4
VOUT(L)
Figure 1. Relative motion of the target is detected by the dual Hall elements mounted on the Hall IC.
ICC
RSENSE
Branded Face
of Package
Rotating Target
I+
IOUT
V+
1
4
VOUT(L)
V+
Figure 2. This left-to-right (pin 1 to pin 4) direction of target rotation
results in a low output signal when a tooth of the target gear is nearest
the face of the package (see figure 3). A right-to-left (pin 4 to pin 1) rotation inverts the output signal polarity.
VOUT(H)
Figure 4: Voltages profiles for high side and low side two-wire sensing.
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ATS645LSH
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
sate for offsets induced by temperature variations over time.
Automatic Gain Control (AGC)
This feature allows the device to operate with an optimal internal
electrical signal, regardless of the air gap (within the AG specification). During calibration, the device determines the peak-topeak amplitude of the signal generated by the target. The gain
of the IC is then automatically adjusted. Figure 5 illustrates the
effect of this feature.
Automatic Offset Adjust (AOA)
The AOA is patented circuitry that automatically cancels the
effects of chip, magnet, and installation offsets. (For capability,
see Dynamic Offset Cancellation, in the Operating Characteristics table.) This circuitry is continuously active, including both
during calibration mode and running mode, compensating for
any offset drift. Continuous operation also allows it to compen-
Digital Peak Detection
A digital DAC tracks the internal analog voltage signal VPROC,
and is used for holding the peak value of the internal analog
signal. In the example shown in figure 6, the DAC would first
track up with the signal and hold the upper peak’s value. When
VPROC drops below this peak value by BOP, the device hysteresis, the output would switch and the DAC would begin tracking
the signal downward toward the negative VPROC peak. Once the
DAC acquires the negative peak, the output will again switch
states when VPROC is greater than the peak by the value BRP. At
this point, the DAC tracks up again and the cycle repeats. The
digital tracking of the differential analog signal allows the IC to
achieve true zero-speed operation.
Ferrous Target
Mechanical Profile
V+
Internal Differential
Analog Signal
Response, without AGC
V+
AGLarge
Internal
Differential
Analog Signal
BOP
BRP
AGSmall
V+
Internal Differential
Analog Signal
Response, with AGC
I+
AGSmall
AGLarge
Figure 5. Automatic Gain Control (AGC). The AGC function corrects for
variances in the air gap. Differences in the air gap affect the magnetic
gradient, but AGC prevents that from affecting device performance, a
shown in the lowest panel.
Device
Output Current
Figure 6: Peak Detecting Switchpoint Detail
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115 Northeast Cutoff
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ATS645LSH
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
Power Supply Protection
The device contains an on-chip regulator and can operate over
a wide VCC range. For devices that need to operate from an
unregulated power supply, transient protection must be added
externally. For applications using a regulated line, EMI/RFI protection may still be required. Contact Allegro MicroSystems for
information on the circuitry needed for compliance with various
EMC specifications. Refer to figure 7 for an example of a basic
application circuit.
Undervoltage Lockout
When the supply voltage falls below the undervoltage lockout
voltage, VCC(UV), the device enters Reset, where the output state
returns to the Power-On State (POS) until sufficient VCC is supplied. ICC levels may not meet datasheet limits when
VCC < VCC(min).
Assembly Description
This device is integrally molded into a plastic body that has been
optimized for size, ease of assembly, and manufacturability.
High operating temperature materials are used in all aspects
of construction.
V+
1
VCC
ATS645
Pins 2 and 3 floating
CBYP
0.01 µF
GND
4
ECU
100 Ω
RSENSE
Figure 7: Typical Application Circuit
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ATS645LSH
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
DEVICE OPERATION
internal analog signal is properly centered.
Each operating mode is described in detail below.
During this mode, the tracking DAC is active and output switching occurs, but the duty cycle is not guaranteed to be within
specification.
Power-On
When power (VCC > VCCMIN) is applied to the device, a short
period of time is required to power the various portions of the
IC. During this period, the ATS645 is guaranteed to power-on in
the high current state, ICC(High).
Initial Offset Adjust
The IC intially cancels the effects of chip, magnet, and installation offsets. Once offsets have been cancelled, the digital tracking DAC is ready to track the signal and provide output switching. The period of time required for both Power-On and Initial
Offset Adjust is defined as the Power-On Time.
Diagnostics
The regulated current output is configured for two wire applications, requiring one less wire for operation than do switches
with the more traditional open-collector output. Additionally,
the system designer inherently gains diagnostics because there
is always output current flowing, which should be in either of
two narrow ranges. Any current level not within these ranges
indicates a fault condition.
Calibration Mode
Running Mode
The calibration mode allows the IC to automatically select
the proper signal gain and continue to adjust for offsets. The
AGC is active, and selects the optimal signal gain based on the
amplitude of the VPROC signal. Following each adjustment to
the AGC DAC, the Offset DAC is also adjusted to ensure the
After the initial calibration period, CI, during which a signal
gain is established, the device moves to Running mode. During Running mode, the IC tracks the input signal and gives an
output edge for every peak of the signal. AOA remains active to
compensate for any offset drift over time.
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ATS645LSH
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
Power Derating
The device must be operated below the maximum junction
temperature of the device, TJ(max). Under certain combinations of
peak conditions, reliable operation may require derating supplied power or improving the heat dissipation properties of the
application. This section presents a procedure for correlating
factors affecting operating TJ. (Thermal data is also available on
the Allegro MicroSystems Web site.)
The Package Thermal Resistance, RJA, is a figure of merit summarizing the ability of the application and the device to dissipate
heat from the junction (die), through all paths to the ambient air.
Its primary component is the Effective Thermal Conductivity,
K, of the printed circuit board, including adjacent devices and
traces. Radiation from the die through the device case, RJC, is
relatively small component of RJA. Ambient air temperature,
TA, and air motion are significant external factors, damped by
overmolding.
The effect of varying power levels (Power Dissipation, PD), can
be estimated. The following formulas represent the fundamental
relationships used to estimate TJ, at PD.
PD = VIN × IIN

(1)
T = PD × RJA (2)
TJ = TA + ΔT
Example: Reliability for VCC at TA = 150°C, package SH
(I1 trim), using minimum-K PCB
Observe the worst-case ratings for the device, specifically:
RJA = 126°C/W, TJ(max) = 165°C, VCC(max) = 24 V, and
ICC(max) = 16 mA.
Calculate the maximum allowable power level, PD(max). First,
invert equation 3:
Tmax = TJ(max) – TA = 165 °C – 150 °C = 15 °C
This provides the allowable increase to TJ resulting from internal
power dissipation. Then, invert equation 2:
PD(max) = Tmax ÷ RJA = 15°C ÷ 126 °C/W = 119 mW
Finally, invert equation 1 with respect to voltage:
VCC(est) = PD(max) ÷ ICC(max) = 119 mW ÷ 16 mA = 7 V
The result indicates that, at TA, the application and device can
dissipate adequate amounts of heat at voltages ≤VCC(est).
Compare VCC(est) to VCC(max). If VCC(est) ≤ VCC(max), then reliable operation between VCC(est) and VCC(max) requires enhanced
RJA. If VCC(est) ≥ VCC(max), then operation between VCC(est) and
VCC(max) is reliable under these conditions.
(3)
For example, given common conditions such as: TA= 25°C,
VCC = 12 V, ICC = 4 mA, and RJA = 140 °C/W, then:
PD = VCC × ICC = 12 V × 4 mA = 48 mW

T = PD × RJA = 48 mW × 140 °C/W = 7°C
TJ = TA + T = 25°C + 7°C = 32°C
A worst-case estimate, PD(max), represents the maximum allowable power level (VCC(max), ICC(max)), without exceeding TJ(max),
at a selected RJA and TA.
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
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12
True Zero Speed Miniature Differential PeakDetecting Gear Tooth Sensor IC
ATS645LSH
Package SH SIP
F
5.50±0.05
0.75
E
0.75 F
B
8.00±0.05
LLLLLLL
NNN
5.80±0.05
E1
E2
YYWW
Branded
Face
1.70±0.10
5.00±0.10
D
4.00±0.10
1
2
3
4
= Supplier emblem
L = Lot identifier
N = Last three numbers of device part number
Y = Last two digits of year of manufacture
W = Week of manufacture
A
0.60±0.10
Standard Branding Reference View
0.71±0.05
For Reference Only, not for tooling use (reference DWG-9003)
Dimensions in millimeters
A Dambar removal protrusion (16X)
24.65±0.10
B Metallic protrusion, electrically connected to pin 4 and substrate (both sides)
C Thermoplastic Molded Lead Bar for alignment during shipment
+0.06
0.38 –0.04
1.00±0.10
13.10±0.10
D Branding scale and appearance at supplier discretion
E Active Area Depth 0.43 mm REF
F
Hall elements (E1, E2); not to scale
A
1.0 REF
1.60±0.10
C
1.27±0.10
0.71±0.10
0.71±0.10
5.50±0.10
Copyright ©2004-2009, Allegro MicroSystems, Inc.
The products described herein are manufactured under one or more of the following U.S. patents: 5,264,783; 5,389,889; 5,442,283; 5,517,112;
5,581,179; 5,619,137; 5,621,319; 5,650,719; 5,686,894; 5,694,038; 5,729,130; 5,917,320; 6,091,239; 6,100,680; 6,232,768; 6,242,908; 6,265,865;
6,297,627; 6,525,531; 6,690,155; 6,693,419; 6,919,720; 7,046,000; 7,053,674; 7,138,793; 7,199,579; 7,253,614; 7,365,530; 7,368,904; or 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’s products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the
failure of that life support device or system, or to affect the safety or effectiveness of that device or system.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use;
nor for any infringement of patents or other rights of third parties which may result from its use.
For the latest version of this document, visit our website:
www.allegromicro.com
Allegro MicroSystems, Inc.
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
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