ATS616 Datasheet

ATS616LSG
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
Features and Benefits
Description
• Self-calibrating for tight timing accuracy
• First-tooth detection
• Immunity to air gap variation and system offsets
• Eliminates effects of signature tooth offsets
• Integrated capacitor provides analog peak and valley
information
• Extremely low timing-accuracy drift with temperature
changes
• Large air gap capability
• Small, integrated package
• Optimized magnetic circuit
• Undervoltage lockout (UVLO)
• Wide operating voltage range
The ATS616 gear-tooth sensor IC is a peak-detecting device
that uses automatic gain control and an integrated capacitor
to provide extremely accurate gear edge detection down to
low operating speeds. Each package consists of a high-temperature plastic shell that holds together a samarium-cobalt
pellet, a pole piece, and a differential open-collector Hall 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.
The technology used for this circuit is Hall-effect based.
The chip incorporates a dual-element Hall IC that switches
in response to differential magnetic signals created by ferromagnetic targets. The sophisticated processing circuitry
contains an A-to-D converter that self-calibrates (normalizes) the internal gain of the device to minimize the effect of
air-gap variations. The patented peak-detecting filter circuit
eliminates magnet and system offsets and has the ability to
discriminate relatively fast changes such as those caused by
tilt, gear wobble, and eccentricities. This easy-to-integrate
solution provides first-tooth detection and stable operation
to extremely low rpm. The ATS616 can be used as a replacement for the ATS612LSB, eliminating the external peakholding capacitor needed by the ATS612LSB.
Package: 4-pin SIP (suffix SG)
Not to scale
Continued on the next page…
Functional Block Diagram
VCC
Voltage
Regulator
Power-On
Logic
UVLO
Tooth and Valley
Comparator
VOUT
Hall
Amp
Gain
Track and
Hold
Current
Limit
Reference
Generator
Hall
Amp
Track and
Hold
GND
TEST
(Recommended)
ATS616LSG-DS, Rev. 4
ATS616LSG
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
Description (continued)
The ATS616 is ideal for use in systems that gather speed, position, and timing information using gear-tooth-based configurations. This device is particularly suited to those applications that
require extremely accurate duty cycle control or accurate edge-
detection, such as automotive camshaft sensing.
TheATS616 is provided in a 4-pin SIP that is Pb (lead) free, with
a 100% matte tin plated leadframe.
Selection Guide
Part Number
Package
ATS616LSGTN-T
4-pin plastic SIP
*Contact Allegro™ for additional packing options
Packing*
800 pieces per 13-in. reel
Absolute Maximum Ratings
Characteristic
Symbol
Notes
Unit
Supply Voltage
VCC
26.5
V
Reverse-Supply Voltage
VRCC
–18
V
Output Off Voltage
See Power Derating section
Rating
VOUTOFF
24
V
Continuous Output Current
IOUT
25
mA
Reverse-Output Current
IROUT
50
mA
–40 to 150
ºC
TJ(max)
165
ºC
Tstg
–65 to 170
ºC
Operating Ambient Temperature
TA
Maximum Junction Temperature
Storage Temperature
L temperature range
Pin-out Diagram
Terminal List Table
1
2
3
Number
Name
1
VCC
2
VOUT
3
Test Pin (tie to GND)
4
GND
4
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115 Northeast Cutoff
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1.508.853.5000; www.allegromicro.com
2
ATS616LSG
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
OPERATING CHARACTERISTICS over operating voltage and temperature range, unless otherwise noted
Characteristic
Symbol Test Condition
Min.
Typ.1
Max.
Units
ELECTRICAL CHARACTERISTICS
Supply Voltage2
VCC
Operating, TJ < 165C
Power-On State
POS
Undervoltage Lockout Threshold
Output On Voltage
VCC(UV)
3.5
–
24
V
VCC = 0 → 5 V
–
HIGH
–
V
VCC = 0 → 5 V; VCC = 5 → 0 V
–
–
3.5
V
–
200
400
mV
VOUT(SAT) IOUT = 20 mA
Supply Zener Clamp Voltage
VZsupply
ICC = 16 mA, TA = 25°C
28
–
–
V
Output Zener Clamp Voltage
VZoutput
IOUT = 3 mA, TA = 25°C
30
–
–
V
Supply Zener Current
IZsupply
VS = 28 V
–
–
15
mA
Output Zener Current
IZoutput
VOUT = 30 V
–
–
3
mA
Output Current Limit
IOUTM
VOUT = 12 V
25
45
55
mA
IOUTOFF
VOUT = 24 V
–
–
15
μA
Output Leakage Current
Supply Current
ICC
VCC > VCC(min)
3
6
12
mA
Power-On Time
tPO
VCC > 5 V
–
80
500
μs
Output Rise Time3
tr
RLOAD = 500 Ω, CS = 10 pF
–
0.3
5.0
μs
Output Fall Time3
tf
RLOAD = 500 Ω, CS = 10 pF
–
0.2
5.0
μs
PERFORMANCE CHARACTERISTICS
Operating Air Gap Range
Operating Magnetic Flux Density
Differential4
Operating Frequency
Initial Calibration
Cycle5
AG
Operating within specification, Target Speed > 10 rpm
0.4
–
2.5
mm
BAG(p-p)
Operating within specification, Target Speed > 10 rpm
60
–
–
G
10
–
10 000
Hz
ƒ
ncal
Output edges before calibration is completed, at fsig < 100 Hz
1
1
1
Edge
Calibration Mode Disable
ndis
Output falling edges for startup calibration to be complete
64
64
64
Edge
Relative Timing Accuracy, Sequential
Eθ
Target Speed = 1000 rpm, BAG(p-p) > 100 G
–
±0.5
±0.75

Target Speed = 1000 rpm, BAG(p-p) > 60 G
–
–
±1.5

Output switching only; may not meet data sheet specifications
–
–
±50
G
Allowable User Induced Differential Offset4
∆BApp
1Typical
data is at VCC = 8 V and TA = 25°C. Performance may vary for individual units, within the specified maximum and minimum limits.
Maximum voltage must be adjusted for power dissipation and junction temperature; see Power Derating section.
3 C is the probe capacitance of the oscilloscope used to make the measurement.
S
4 10 G = 1 mT (millitesla), exactly.
5Non-uniform magnetic profiles may require additional edges before calibration is complete.
2
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
ATS616LSG
Reference Target (Gear) Information
REFERENCE TARGET 60+2
Characteristics
Symbol
Test Conditions
Typ.
Unit
120
mm
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
Signature Region Circular Tooth Length
tSIG
Length of signature tooth,
with respect to branded face;
measured at Do
15
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
Branded Face
of Package
t,t
SI
G
Outside Diameter
Symbol Key
tV
ØDO
F
ht
Air Gap
Signature Region
Pin 4
Pin 1
Branded Face
of Package
Reference Target
60+2
Figure 1. Configuration with Radial-Tooth Reference Target
For the generation of adequate magnetic field levels, the following recommendations should be followed in the design and
specification of targets:
• 2 mm < tooth width, t < 4 mm
• Valley width, tv > 2 mm
• Valley depth, ht > 2 mm
• Tooth thickness, F ≥ 3 mm
• Target material must be low carbon steel
Although these parameters apply to targets of traditional
geometry (radially oriented teeth with radial sensing, shown in
figure 1), they also can be applied in applications using stamped
targets (an aperture or rim gap punched out of the target material) and axial sensing. For stamped geometries with axial sensing, the valley depth, ht, is intrinsically infinite, so the criteria for
tooth width, t, valley width, tv, tooth material thickness, F, and
material specification need only be considered for reference. For
example, F can now be < 3 mm.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
ATS616LSG
Characteristic Data
Supply Current (On) versus Supply Voltage
9
9
8
8
7
7
6
TA (°C)
–40
25
85
150
5
4
3
2
ICCON (mA)
ICCOFF (mA)
Supply Current (Off) versus Supply Voltage
6
4
3
2
1
1
0
0
0
5
10
15
VCC (V)
20
25
30
0
Supply Current (Off) versus Ambient Temperature
9
9
8
8
10
15
VCC (V)
5
3.5
5.0
12
24
4
3
ICCON (mA)
VCC (V)
25
30
6
VCC (V)
5
3.5
5.0
12
24
4
3
2
2
1
1
0
0
0
50
100
150
–50
200
0
50
100
150
200
TA (°C)
TA (°C)
Output Voltage (On) versus Ambient Temperature
Output Leakage Current versus Ambient Temperature
350
1.2
300
1.0
250
ISINK(mA)
200
20
150
0.8
IOUTOFF (µA)
VOUT(SAT) (mV)
20
7
6
–50
5
Supply Current (On) versus Ambient Temperature
7
ICCOFF (mA)
TA (°C)
–40
25
85
150
5
VOUT (V)
10
0.6
0.4
100
0.2
50
0
0
–50
0
50
100
TA (°C)
150
200
–50
0
50
100
150
200
TA (°C)
Continued on the next page.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
ATS616LSG
Characteristic Data (continued)
Relative Timing Accuracy versus Air Gap
Relative Timing Accuracy versus Air Gap
Sequential Tooth Falling Edge
Sequential Tooth Rising Edge
1000 rpm
1.5
1.0
TA (°C)
0.5
–40
0
0.0
25
85
125
150
-0.5
-1.0
0
0.5
1.0
1.5
2.0
2.5
Edge Position (°)
Edge Position (°)
1.0
-1.5
25
85
125
150
-0.5
-1.0
0
0.5
1.0
1.5
2.0
2.5
AG (mm)
Relative Timing Accuracy versus Air Gap
Relative Timing Accuracy versus Air Gap
Signature Tooth Falling Edge
1000 rpm
Signature Tooth Rising Edge
1000 rpm
1.5
3.0
1.0
TA (°C)
0.5
–40
0
25
85
125
150
0.0
-0.5
-1.0
0
0.5
1.0
1.5
AG (mm)
2.0
2.5
3.0
Edge Position (°)
1.0
Edge Position (°)
–40
0
0.0
-1.5
3.0
TA (°C)
0.5
AG (mm)
1.5
-1.5
1000 rpm
1.5
TA (°C)
0.5
–40
0
25
85
125
150
0.0
-0.5
-1.0
-1.5
0
0.5
1.0
1.5
2.0
2.5
3.0
AG (mm)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
6
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
ATS616LSG
Characteristic Data (continued)
Relative Timing Accuracy versus Ambient Temperature
Relative Timing Accuracy versus Ambient Temperature
Sequential Tooth Falling Edge
Signature Tooth Falling Edge
0.5 mm
1.5
1.0
rpm
0.5
10
100
0.0
500
1000
1500
2000
-0.5
-1.0
–50
0
50
100
150
Edge Position (°)
Edge Position (°)
1.0
-1.5
0.5 mm
1.5
10
100
0.0
500
1000
1500
2000
-0.5
-1.0
-1.5
200
rpm
0.5
–50
0
50
100
150
200
TA (°C)
TA (°C)
Relative Timing Accuracy versus Ambient Temperature
Relative Timing Accuracy versus Ambient Temperature
Sequential Tooth Rising Edge
0.5 mm
Signature Tooth Rising Edge
0.5 mm
1.5
1.5
1.0
rpm
0.5
10
100
500
1000
1500
2000
0.0
-0.5
-1.0
-1.5
–50
0
50
100
TA (°C)
150
200
Edge Position (°)
Edge Position (°)
1.0
rpm
0.5
10
100
500
1000
1500
2000
0.0
-0.5
-1.0
-1.5
–50
0
50
100
150
200
TA (°C)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
ATS616LSG
THERMAL CHARACTERISTICS may require derating at maximum conditions, see application information
Characteristic
Symbol
RθJA
Package Thermal Resistance
Test Conditions*
Value
Units
Single-sided PCB with copper limited to solder pads
126
ºC/W
Two-sided PCB with copper limited to solder pads and 3.57 in.2
(23.03 cm2) of copper area each side, connected to GND 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
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
8
ATS616LSG
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
Functional Description
Assembly Description. The ATS616 is a Hall IC/rare earth
pellet configuration that is fully optimized to provide digital response to gear tooth edges. This device is packaged in a
molded miniature plastic body that has been optimized for size,
ease of assembly, and manufacturability. High operating temperature materials are used in all aspects of construction.
After proper power is applied to the component, the IC is
capable of instantly providing digital information that is representative of the profile of a rotating gear. No additional optimization or processing circuitry is required. This ease of use should
reduce design time and incremental assembly costs for most
applications.
Hall Technology. The package contains a single-chip differential
Hall effect sensor IC, a samarium cobalt pellet, and a flat ferrous
pole piece (figure 2). The Hall IC consists of 2 Hall elements
(spaced 2.2 mm apart) located so as to measure the magnetic
gradient created by the passing of a ferromagnetic object. The
two elements measure the magnetic gradient and convert it to an
analog voltage that is then processed in order to provide a digital
output signal.
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.
Internal Electronics. The processing circuit uses a patented
peak detection scheme to eliminate magnet and system offsets.
This technique allows dynamic coupling and filtering of offsets
without the power-up and settling time disadvantages of classical
high-pass filtering schemes. The peak signal of every tooth and
valley is detected by the filter and is used to provide an instant
reference for the operate and release point comparator. In this
manner, the thresholds are adapted and referenced to individual
signal peaks and valleys, providing immunity to zero line variation from 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 for small value filter capacitors.
The ATS616 also includes self-calibration circuitry that is
engaged at power on. The signal amplitude is measured, and
then the device gain is normalized. In this manner switchpoint
drift versus air gap is minimized, and excellent timing accuracy
can be achieved.
The AGC (Automatic Gain Control) circuitry, in conjunction
with a unique hysteresis circuit, also eliminates the effect of
gear edge overshoot as well as increases the immunity to false
switching caused by gear tooth anomalies at close air gaps. The
B+
Differential
Magnetic Flux
Target (Gear)
BOP
BOP
0
BRP
Element Pitch
Hall Element 2
Dual-Element
Hall Effect Device
South Pole
North Pole
(Pin n >1 Side)
Hall Element 1
Hall IC
Pole Piece
(Concentrator)
Back-biasing
rare-earth pellet
Case
(Pin 1 Side)
BRP
B–
VCC
Device Output
VOUT
VOUT(sat)
Figure 2. Relative motion of the target is detected by the dual Hall elements mounted on the Hall IC.
Figure 3. The peaks in the resulting differential signal are used to set the
operate, BOP , and release, BRP , switchpoints.
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
9
ATS616LSG
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
AGC circuit sets the gain of the device after power-on. Up to a
0.25 mm air gap change can occur after calibration is complete
without significant performance impact.
Superior Performance. The ATS616 has several advantages
over conventional Hall-effect devices. The signal-processing
techniques used in the ATS616 solve the catastrophic issues that
affect the functionality of conventional digital gear-tooth sensors, such as the following:
• Temperature drift. Changes in temperature do not greatly
affect this device due to the stable amplifier design and the
offset rejection circuitry.
monly used (Hall-effect element mounted on the face of a simple
permanent magnet) requires the detection of a small signal (often
<100 G) that is superimposed on a large back-biased field, often
1500 G to 3500 G. For most gear/target configurations, the backbiased field values change due to concentration effects, resulting
in a varying baseline with air gap, valley widths, eccentricities,
and vibration (figure 4). The differential configuration (figure 5)
cancels the effects of the back-biased field and avoids many of
the issues presented by the single Hall element design.
Peak Detecting vs. AC-Coupled Filters. High-pass filtering
• Timing accuracy variation due to air gap. The accuracy variation caused by air gap changes is minimized by the self-calibration circuitry. A 2×-to-3× improvement can be seen.
• Dual edge detection. Because this device switches based on
the positive and negative peaks of the signal, dual edge detection is guaranteed.
• Tilted or off-center installation. Traditional differential sensor
ICs can switch incorrectly due to baseline changes versus air
gap caused by tilted or off-center installation. The peak detector circuitry references the switchpoint from the peak and is
immune to this failure mode. There may be a timing accuracy
shift caused by this condition.
• Large operating air gaps. Large operating air gaps are achievable with this device due to the sensitive switchpoints after
power-on (dependent on target dimensions, material, and
speed).
Figure 4. Affect of varying valley widths on single-element circuits.
• Immunity to magnetic overshoot. The patented adjustable
hysteresis circuit makes the ATS616 immune to switching on
magnetic overshoot within the specified air gap range.
• Response to surface defects in the target. The gain-adjust
circuitry reduces the effect of minor gear anomalies that would
normally cause false switching.
• Immunity to vibration and backlash. The gain-adjust circuitry
keeps the hysteresis of the device roughly proportional to the
peak-to-peak signal. This allows the device to have good immunity to vibration even when operating at close air gaps.
• Immunity to gear run out. The differential chip configuration
eliminates the baseline variations caused by gear run out.
Differential vs. Single-Element Design. The differential chip
configuration is superior in most applications to the classical
single-element design. The single-element configuration com-
Figure 4. Affect of varying air gaps on differential circuits.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
10
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
ATS616LSG
(normal AC coupling) is a commonly used technique for eliminating circuit offsets. However, AC coupling has errors at poweron because the filter circuit needs to hold the circuit zero value
even though the circuit may power-on over a large signal. Such
filtering techniques can only perform properly after the filter
has been allowed to settle, which typically takes longer than 1s.
Also, high-pass filter solutions cannot easily track rapidly changing baselines, such as those caused by eccentricities. (The term
baseline refers to a 0 G differential field, where each Hall-effect
element is subject to the same magnetic field strength; see figure
3.) In contrast, peak detecting designs switch at the change in
slope of the differential signal, and so are baseline-independent
both at power-on and while running.
Peak Detecting vs. Zero-Crossing Reference. The usual dif-
ferential zero-crossing sensor ICs are susceptible to false switching due to off-center and tilted installations that result in a shift
of the 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 detection techniques, increased air
gap capabilities can be expected because peak detection utilizes
the entire peak-to-peak signal range, as compared to zero-crossing detectors, which switch at half the peak-to-peak signal.
This prevents false signals, which may be caused by undervoltage conditions (especially during power-up), from appearing at
the output.
Output. The device output is an open-collector stage capable of
sinking up to 20 mA. An external pull-up (resistor) must be supplied to a supply voltage of not more than 24 V.
Output Polarity. The output of the unit will switch from low to
high as the leading edge of a tooth passes the branded face of the
package in the direction indicated in figure 6. This means that in
such a configuration, the output voltage will be high when the
package is facing a tooth. If the target rotation is in the opposite direction relative to the package, the output polarity will be
opposite as well, with the unit switching from low to high as the
leading edge passes the unit.
Branded Face
of Package
Rotating Target
Power-On Operation. The device powers-on in the Off state
(output voltage high), irrespective of the magnetic field condition. The power-up time of the circuit is no greater than 500 μs.
The circuit is then ready to accurately detect the first target edge
that results in a high-to-low transition of the device output.
Undervoltage Lockout (UVLO). When the supply voltage, VCC ,
is below the minimum operating voltage, VCC(UV) , the device is
off and stays off, irrespective of the state of the magnetic field.
1
Figure 6. This left-to-right (pin 1 to pin 4) direction of target rotation
results in a high output signal when a tooth of the target gear is nearest
the branded face of the package. A right-to-left (pin 4 to pin 1) rotation
inverts the output signal polarity.
Target
Mechanical Profile
Target
Magnetic Profile
4
Signature Tooth
B+
BIN
IC Output
Switch State
On
Off
On
Off
On
Off
On
Off
On
Off
On Off On Off On Off
V+
IC Output
Electrical Profile
Target Motion from
Pin 1 to Pin 4
VOUT
IC Output
Electrical Profile
Target Motion from
Pin 4 to Pin 1
VOUT
V+
Figure 7. The magnetic profile reflects the geometry of the target, allowing the device to present an accurate digital output response.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
11
ATS616LSG
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect 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
(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
able power level (VCC(max), ICC(max)), without exceeding TJ(max),
at a selected RJA and TA.
Example: Reliability for VCC at TA = 150°C, package SG, 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) = 12 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 ÷ 12 mA = 9.92 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.
This value applies only to the voltage drop across the ATS616
chip. If a protective series diode or resistor is used, the effective maximum supply voltage is increased. For example, when a
standard diode with a 0.7 V drop is used:
VCC(max) = 9.9 V + 0.7 V = 10.6 V
TJ = TA + T = 25°C + 7°C = 32°C
A worst-case estimate, PD(max), represents the maximum allow-
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
12
ATS616LSG
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
Device Evaluation: EMC (Electromagnetic Compatibility)
Characterization Only
Test Name*
Reference Specification
ESD – Human Body Model
AEC-Q100-002
ESD – Machine Model
AEC-Q100-003
Conducted Transients
ISO 7637-1
Direct RF Injection
ISO 11452-7
Bulk Current Injection
ISO 11452-4
TEM Cell
ISO 11452-3
*Please contact Allegro MicroSystems for EMC performance
Mechanical Information
Component
Material
Description
Value
Package Material
Thermoset Epoxy
Maximum Temperature
170°Ca
Leads
Copper
0.016 in. thick
aTemperature
excursions of up to 225°C for 2 minutes or less are permitted.
accepted soldering techniques are acceptable for this package as long as the indicated maximum temperature is not exceeded.
Additional soldering information is available on the Allegro Web site.
bIndustry
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
13
Dynamic Self-Calibrating Peak-Detecting Differential
Hall Effect Gear Tooth Sensor IC
ATS616LSG
Package SG, 4-Pin SIP
5.50±0.05
F
2.20
E
B
8.00±0.05
LLLLLLL
NNN
5.80±0.05
E1
YYWW
Branded
Face
E2
1.70±0.10
D
4.70±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
0.71±0.05
0.60±0.10
Standard Branding Reference View
For Reference Only, not for tooling use (reference DWG-9002)
Dimensions in millimeters
A Dambar removal protrusion (16X)
+0.06
0.38 –0.04
B Metallic protrusion, electrically connected to pin 4 and substrate (both sides)
C Thermoplastic Molded Lead Bar for alignment during shipment
24.65±0.10
D Branding scale and appearance at supplier discretion
0.40±0.10
15.30±0.10
E
Active Area Depth, 0.43 mm
F
Hall elements (E1, E2), not to scale
1.0 REF
A
1.60±0.10
C
1.27±0.10
0.71±0.10
0.71±0.10
5.50±0.10
Copyright ©2005-2013, Allegro MicroSystems, LLC
Allegro MicroSystems, LLC 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, LLC 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, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
14
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