Allegro ATS468 Wide operating voltage range Datasheet

ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
FEATURES AND BENEFITS
• Wide operating voltage range
• Peak detecting algorithm robust against signal
perturbations
• Capable of sensing a wide range of target types
• Running mode calibration for continuous optimization
• Single chip IC for high reliability
• Precise duty cycle signal throughout operating
temperature range
• Large operating air gaps
• Automatic Gain Control (AGC) for air-gap–independent
switchpoints
• Automatic Offset Adjustment (AOA) for signal
processing optimization
• True zero-speed operation
Continued on the next page…
Packages:
4-Pin SIP (suffix SG)
4-Pin SIP (suffix SJ)
DESCRIPTION
The ATS468 is a true zero-speed gear tooth sensor IC consisting
of an optimized Hall IC and a permanent magnet pellet
configuration in a single overmolded package. The integrated
circuit provides a manufacturer-friendly solution for digital
gear tooth sensing applications. This small package can be
easily assembled and used in conjunction with gears of various
shapes and sizes.
The integrated circuit incorporates dual Hall effect elements
with a 2.2 mm spacing and signal processing that switches
in response to differential magnetic signals created by a
ferromagnetic target. The circuitry contains a sophisticated
digital circuit to reduce system offsets, to calibrate the gain for
air-gap–independent switchpoints, and to achieve true zerospeed operation. Signal optimization occurs at power-on through
the combination of offset and gain adjust, and is maintained
throughout the operating time with the use of a running-mode
calibration. The running-mode calibration provides immunity
to environmental effects such as micro-oscillations of the target
or sudden air gap changes.
The device is ideally suited to obtaining speed and duty cycle
information in gear tooth–based speed, position, and timing
applications, such as in speedometers.
Continued on the next page…
Not to scale
VCC
E1
Hall
Amplifier
∑
Internal
Regulator
Gain
E2
Automatic Offset
Adjustment (AOA)
Control
AOA DAC
Automatic Gain
Control (AGC)
AGC DAC
Tracking DAC
Peak Hold
OUT
+
–
Current
Limit
Test Signals
TEST
GND
Functional Block Diagram
ATS468-DS
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
ATS468
Description (continued)
Features and Benefits (continued)
• Undervoltage lockout
• Reverse battery protection
• Robust test coverage capability with Scan Path and IDDQ
measurement
The ATS468 is available in two 4-pin SIPs (suffix SG and SJ). The
packages are lead (Pb) free, with 100% matte tin leadframe plating.
SPECIFICATIONS
Selection Guide
Part Number
Package
Packing*
ATS468LSGTN-T
ATS468LSJTN-T
4-pin through hole SIP
4-pin through hole SIP
800 pieces per reel
800 pieces per reel
Operating Ambient
Temperature Range, TA
(°C)
-40 to 150
-40 to 150
*Contact Allegro™ for additional packing options.
Absolute Maximum Ratings
Characteristic
Symbol
Notes
Rating
Unit
28
V
Forward Supply Voltage
VCC
Reverse Supply Voltage
VRCC
–18
V
Output Current
IOUT
30
mA
Reverse Output Current
IROUT
–50
mA
Reverse Output Voltage
VROUT
–0.5
V
Output Off Voltage
VOUT
28
V
Refer to Power Derating Curves chart
Operating Ambient Temperature
TA
–40 to 150
ºC
Maximum Junction Temperature
TJ(max)
165
ºC
Tstg
–65 to 170
ºC
Storage Temperature
L temperature range
Terminal List Table
Branded
Face
1
2
3
Number
Name
Function
1
VCC
2
VOUT
Output
3
TEST
Test pin, float
4
GND
Ground
Supply voltage
4
Package SG and SJ, 4-Pin SIP Pin-out Diagram
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2
ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
OPERATING CHARACTERISTICS: valid throughout operating voltage and ambient temperature ranges using Allegro reference target 60-0, typical data applies at VCC = 12 V and TA = 25°C; unless otherwise specified
Characteristics
Symbol
Test Conditions
Min.
Typ.
Max.
Unit1
Operating, TJ ≤ 165°C
4
–
26.5
V
VCC = 0 → VCC(min) + 1 V and
VCC(min) + 1 V → 0 V
–
–
VCC(min)
V
3.0
5.0
7.5
mA
Electrical Characteristics
Supply Voltage2
Undervoltage Lockout
Supply Current
VCC
VCC(uv)
ICC
VCC > VCC(min)
Power-On Characteristics
Power-On State
POS
Power-On Time3
tPO
VOUT, connected as in figure 6
–
High
–
V
VCC > VCC(min)
–
–
2.3
ms
ICC = ICC(max) + 3 mA, TA = 25 °C
38
–
–
V
mA
mA
Transient Protection Characteristics
Supply Zener Clamp Voltage
Supply Zener Current
Reverse Supply Current
VZ(supply)
IZ(supply)
IRCC
Vsupply = 38 V
–
–
ICC(max)
+3
VRCC = –18 V, TJ < TJ(max)
–
–
–1
Output Zener Clamp Voltage
VZ(output)
IOUT = 3 mA, TA = 25°C
28
–
–
V
Output Zener Current
IZ(output)
VOUT = 28 V
–
–
3
mA
Output Current Limit
IOUT(lim)
30
–
85
mA
IOUT(sink) = 20 mA
–
220
400
mV
VOUT = 24 V, output off
–
–
10
µA
RPU = 1 kΩ, VPU = 20 V, COUT = 10 pF
–
2
–
µs
Output Stage Characteristics
Output Saturation Voltage
Output Leakage Current
Output Fall Time
VOUT(sat)
IOFF
tf
11
G (gauss) = 0.1 mT (millitesla).
voltage operation must not exceed maximum junction temperature. Refer to Power Derating Curves chart.
3Time required to initialize device. Power-On Time includes the time required to complete the internal automatic offset adjust. The DAC is then ready for peak acquisition.
2Maximum
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115 Northeast Cutoff
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3
ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
OPERATING CHARACTERISTICS (continued): valid throughout operating voltage and ambient temperature ranges using
Allegro reference target 60-0, typical data applies at VCC = 12 V and TA = 25°C; unless otherwise specified
Characteristics
Symbol
Test Conditions
Min.
Typ.
Max.
Unit1
DOUT within specification
0.5
–
3.5
mm
20
–
1200
G
–
120
–
mV
3
–
10
G
–
120
–
mV
Performance Characteristics
Operational Air Gap Range2
AG
Operating Magnetic Signal Range
BDIFF
Peak-to-peak of differential signal; operation
within specification
Operate Point3
BOP
See figure 5
Release Point3
BRP
Operating Frequency
fOP
Analog Signal Bandwidth
BW
ncal
Initial Calibration Cycle4
See figure 5
3
–
10
G
0
–
10
kHz
Equivalent to f = –3 dB
20
–
–
kHz
Output rising edges before calibration is
completed, 0 offset, fOP ≤ 200 Hz
–
–
3
edge
Output Duty Cycle Precision
DOUT
Using a pure sine magnetic signal, with fOP and
BDIFF within specification
–
–
±15
%
Output Period Precision
TOUT
Using pure sine magnetic signal with
BDIFF = 50 Gpk-pk and fOP = 1 kHz
–
0.3
–
%
–60
–
60
G
Allowable User Induced Differential
Offset
BDIFFEXT
Output switching only
11
G (gauss) = 0.1 mT (millitesla).
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.
3Values in G are based on device in maximum gain setting.
4Non-uniform magnetic profiles may require additional output pulses before calibration is complete.
2AG
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115 Northeast Cutoff
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ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
Thermal Characteristics may require derating at maximum conditions, see Power Derating section
Characteristic
Package Thermal Resistance
Symbol
Test Conditions*
Single layer PCB, with copper limited to solder pads
RθJA
Single layer PCB, with copper limited to solder pads and 3.57
(23.03 cm2) copper area each side
in.2
Value
Unit
126
ºC/W
84
ºC/W
*Additional thermal information available on the Allegro website
Maximum Allowable VCC (V)
Power Derating Curve
27
26
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 °C/W)
(RθJA = 126 °C/W)
VCC(min)
20
40
60
80
100
120
140
160
180
Temperature (°C)
Power Dissipation, PD (m W)
Power Dissipation versus Ambient Temperature
1900
1800
1700
1600
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
RqJA = 84 ºC/W
RqJA = 126 ºC/W
20
40
60
80
100
120
Temperature (°C)
140
160
180
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115 Northeast Cutoff
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Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
ATS468
CHARACTERISTIC PERFORMANCE
Supply Current (Output On) versus Supply Voltage
7
6
6
Supply Current, Icc (mA)
Supply Current, Icc (mA)
Supply Current (Output On) versus Temperature
7
5
4
Vcc (V)
3
4
2
12
5
4
TA (°C)
3
-40
2
25
85
1
1
26.5
150
0
0
-50
-25
0
25
50
75
100
125
0
150
5
Ambient Temperature, TA (ºC)
20
25
30
Supply Current (Output Off) versus Supply Voltage
7
6
6
Supply Current, Icc (mA)
Supply Current, Icc (mA)
Supply Current (Output Off) versus Temperature
5
4
Vcc (V)
4
2
12
1
5
4
TA (°C)
3
-40
2
25
85
1
26.5
150
0
0
-50
-25
0
25
50
75
100
125
150
0
5
Ambient Temperature, T A (°C)
Output Saturaon Voltage versus Temperature
500
I OUT(mA)
450
10
15
20
25
400
350
300
250
200
150
100
50
0
-50
-25
0
25
50
75
100
Ambient Temperature, TA (°C)
10
15
20
25
30
Supply Voltage, Vcc ( V)
125
150
Output Saturation Voltage, VOUT(sat)(mV)
Output Saturation Voltage, VOUT(sat)(mV)
15
Supply Voltage, Vcc (V)
7
3
10
Output Saturaon Voltage versus Output Current
500
TA (°C)
450
400
-40
350
25
300
85
250
150
200
150
100
50
0
0
5
10
15
20
25
30
Output Current, I OU T (mA)
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115 Northeast Cutoff
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Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
ATS468
REFERENCE TARGET CHARACTERISTICS
Reference Target 60-0
Symbol
Test Conditions
Typ.
Unit
120
mm
Outside Diameter
Do
Outside diameter of target
Face Width
F
Breadth of tooth, with respect to
branded face
6
mm
Angular Tooth Thickness
t
Length of tooth, with respect to
branded face; measured at Do
3
deg.
Angular Valley Thickness
tv
Length of valley, with respect to
branded face; measured at Do
3
deg.
Tooth Whole Depth
ht
3
mm
–
–
Material
Low Carbon Steel
Symbol Key
Branded Face
of Package
Do
ht
F
t tv
Characteristics
Air Gap
Reference Gear Magnetic Gradient Amplitude
With Reference to Air Gap
Branded Face
of Package
1200
Pin4
1000
Pin1
800
600
400
200
0
0.5
1
1.5
2
2.5
3
Reference Target 60-0
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
Magnetic Flux Density, BDIFF (G)
1400
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 (°)
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Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
ATS468
FUNCTIONAL DESCRIPTION
Sensing Technology
Determining Output Signal Polarity
The ATS468 contains a single-chip differential Hall-effect sensor
IC, a permanent magnet pellet, and a flat ferrous pole piece (concentrator). As shown in Figure 1, the Hall IC supports two Hall
elements, which sense the magnetic profile of the ferrous gear
target simultaneously, but at different points (spaced at a 2.2 mm
pitch), generating a differential internal analog voltage, VPROC,
that is processed for precise switching of the digital output signal.
In Figure 3 the top panel, labeled Mechanical Position, represents
the mechanical features of the target gear and orientation to the
device. The bottom panel, labeled Device Output Signal, displays
the square waveform corresponding to the digital output signal
that results from a rotating gear configured as shown in Figure 2,
and electrically connected as in Figure 6. That direction of rotation (of the gear side adjacent to the package face) 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
low state to high state 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 switches to its high polarity when a tooth is the target feature nearest to the package. If the
direction of rotation is reversed, so that the gear rotates from the
pin 4 side to the pin 1 side, then the output polarity inverts. That
is, the output signal goes high when a falling edge is detected,
and a valley is nearest to the package.
The Hall IC is self-calibrating and also possesses a temperature
compensated amplifier and offset cancellation circuitry. The
built-in 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 compensation circuitry. The Hall transducers and signal
processing electronics are integrated on the same silicon substrate, using a proprietary BiCMOS process.
Target Profiling During Operation
An operating device is capable of providing digital information
that is representative of the mechanical features of a rotating gear.
The waveform diagram 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 ATS468. No additional optimization is needed and minimal processing circuitry is
required. This ease of use reduces design time and incremental
assembly costs for most applications.
Mechanical Position (Target movement pin 1 to pin 4)
This tooth sensed earlier
This tooth sensed
later
Target
(Gear)
Target Magnetic Profile
+B
Device Orientation to Target
Hall Element Pitch
Branded Face
Target (Gear)
IC
Element Pitch
Hall Element 2
Dual-Element
Hall Effect Device
South Pole
Hall Element 1
Hall IC
Pole Piece
(Concentrator)
North Pole
Permanent
Magnet Pellet
Case
(Pin 4 Side)
Back-Biasing
Permanent Magnet Pellet
Sensor Branded Face
Pin 4 Side
Pin 1 Side
(Package Top View)
Device Internal Differential Analog Signal, VPROC
(Pin 1 Side)
Figure 1: Relative Motion of the Target
Relative Motion of the Target is Detected by the Dual Hall Elements
in the Hall IC.
Device Internal Switch State
Branded Face
of Sensor
Rotating Target
Off
On
Off
On
Device Output Signal, VOUT
Pin 1
Pin 4
Figure 2: Left-to-Right Direction of Target Rotation
This left-to-right (pin 1 to pin 4) direction of target rotation results
in a high output state when a tooth of the target gear is nearest the
package face (see figure 3). A right-to-left (pin 4 to pin 1) rotation
inverts the output signal polarity.
Figure 3: Magnetic Profile
The magnetic profile reflects the geometry of the target, allowing the
ATS468 to present an accurate digital output response.
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115 Northeast Cutoff
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8
ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
Automatic Gain Control (AGC)
This feature allows the device to operate with an optimal internal
electrical signal, regardless of the differential signal amplitude
(within the BDIFF and BDIFFEXT specifications). During calibration, the device determines the peak-to-peak amplitude of the
signal generated by the target. The gain of the device is then automatically adjusted. Figure 4 illustrates the effect of this feature.
During running mode, the AGC continues to monitor the system
amplitude, reducing the gain if necessary; see the Device Operation section for more details.
Automatic Offset Adjust (AOA)
The AOA is patented circuitry that automatically compensates for
the effects of chip, magnet, and installation offsets. This circuitry
is continuously active, including both during calibration mode
and running mode, compensating for offset drift. Continuous
operation also allows it to compensate for offsets induced by
temperature variations over time.
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 5, 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. After 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 device
to achieve true zero-speed operation.
Target
Ring Magnet
N
S
N
S
V+
Internal Differential
Analog Signal
Response, without AGC
AGLarge
AGSmall
V+
Internal Differential
Analog Signal
Response, with AGC
AGSmall
AGLarge
Figure 4: 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, as shown in the lowest panel.
V+
Internal
Differential
Analog Signal,
VPROC
0
BOP
BOP
BRP
BRP
V–
VCC
Device Output,
VOUT
VOUT(sat)
Figure 5: The Peaks in the Resulting Differential Signal
are Used to Set the Operate, BOP , and Release, BRP ,
Switchpoints.
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ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
Power Supply Protection
gets ready to track the VPROC signal. After power-on, there are
conditions that could induce a change in the output state. Such an
event could be caused by thermal transients, but would require a
static applied magnetic field, proper signal polarity, and particular
direction and magnitude of internal signal drift.
The device contains an on-chip regulator and can operate
throughout a wide VCC range. For devices that must be operated
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 for
information on the circuitry required for compliance with various
EMC specifications. Refer to figure 6 for an example of a basic
application circuit.
Initial Offset Adjust The device initially cancels the effects of
chip, magnet, and installation offsets. After offsets have been
cancelled, the device is ready to provide the first output switch.
The period of time required for both Power-On and Initial Offset
Adjust is defined as the Power-On Time.
Undervoltage Lockout
Calibration Mode The calibration mode allows the device to
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.
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 internal analog signal is properly centered.
Assembly Description
During this mode, the tracking DAC is active and output switching occurs, but the duty cycle is not guaranteed to be within
specification.
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.
Running Mode After the Initial Calibration period, CI, establishes a signal gain, the device moves to running mode. During
running mode, the device 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.
Device Operation
Each operating mode is described in detail below.
Power-On When power (VCC > VCC(min)) is applied to the
The ATS468 incorporates an algorithm for adjusting the signal
gain during running mode. This algorithm is designed to optimize
the VPROC signal amplitude in instances where the magnetic
device, a short period of time is required to power the various
portions of the IC. During this period, the ATS468 powers-on in
the high voltage state, VOUT(high), and the digital tracking DAC
Vsupply
VPU
RS
100 Ω
VCC
CBYP
0.1 µF
RPU
1 kΩ
ATS468
TEST
OUT
GND
VOUT
COUT
Figure 6: Typical Application Diagram
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10
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
ATS468
signal “seen” during the calibration period is not representative of
the amplitude of the magnetic signal for the installed device air
gap (see figure 7). Note that in this mode, the gain can be reduced
but not increased, so this algorithm applies only to instances in
which the magnetic signal amplitude during running is higher
than that during calibration.
1
2
3
4
5
BOP
Internal Differential
Signal, VPROC
BOP
BRP
BRP
Device Electrical
Output, VOUT
Figure 7: Operation of Running Mode Gain Adjust
• Position1. The device is initially powered-on. Self-calibration occurs.
• Position 2. Small amplitude oscillation of the target sends an erroneously small differential signal to the device. The amplitude of VPROC is
greater than the switching hysteresis (BOP and BRP), and the device output switches.
• Position 3. The calibration period completes on the third rising output edge, and the device enters running mode.
• Position 4. True target rotation occurs and the correct magnetic signal is generated for the installation air gap. The established signal gain
is too large for the target rotational magnetic signal at the given air gap.
• Position 5. Running mode calibration corrects the signal gain to an optimal level for the installation air gap.
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11
ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
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, RθJA, 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, RθJC, is relatively
small component of RθJA. 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)
ΔT = PD × RθJA
(2)
TJ = TA + ΔT
(3)
For example, given common conditions such as: TA= 25°C,
VCC = 12 V, ICC = 5 mA, and RθJA = 126 °C/W, then:
A worst-case estimate, PD(max), represents the maximum allowable power level (VCC(max) , ICC(max)), without exceeding
TJ(max), at a selected RθJA and TA.
Example: Reliability for VCC at TA = 150°C, package SG or SJ
using single-layer PCB.
Observe the worst-case ratings for the device, specifically:
RθJA = 126°C/W, TJ(max) = 165°C, VCC(max) = 26.5 V, and
ICC(max) = 7.5 mA.
Calculate the maximum allowable power level, PD(max). First,
invert equation 3:
ΔTmax = 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) = ΔTmax ÷ RθJA = 15°C ÷ 126 °C/W = 119 mW
Finally, invert equation 1 with respect to voltage:
VCC(est) = PD(max) ÷ ICC(max) = 119 mW ÷ 7.5 mA = 15.9 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 RθJA. If VCC(est) ≥ VCC(max), then operation between
VCC(est) and VCC(max) is reliable under these conditions.
PD = VCC × ICC = 12 V × 5 mA = 60 mW
ΔT = PD × RθJA = 60 mW × 126 °C/W = 7.6°C
TJ = TA + ΔT = 25°C + 7.6°C = 32.6°C
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
12
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
ATS468
PACKAGE OUTLINE DRAWINGS
5.50 ±0.05
F
2.20
E
B
8.00 ±0.05
LLLLLLL
NNN
E1
5.80 ±0.05
E2
F
F
YYWW
Branded
Face
1.70 ±0.10
D Standard Branding Reference View
4.70 ±0.10
1
2
3
4
L
N
Y
W
A
0.60 ±0.10
0.71 ±0.05
= Supplier emblem
= Lot identifier
= Last three numbers of device part number
= Last two digits of year of manufacture
= Week of manufacture
For Reference Only, not for tooling use (reference DWG-9200)
Dimensions in millimeters
A Dambar removal protrusion (16X)
0.38
+0.06
–0.04
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
D Branding scale and appearance at supplier discretion
E Active Area Depth, 0.43 mm
0.40 ±0.10
15.30 ±0.10
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
Figure 8: Package SG, 4-Pin SIP
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
13
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
ATS468
5.50 ±0.05
F
2.20
E
B
8.00 ±0.05
LLLLLLL
E1 F
NNN
E2 F
YYWW
Branded
Face
5.80 ±0.05
1.70 ±0.10
D Standard Branding Reference View
A
5.30 ±0.10
1
6.60 ±0.10
2
3
L
N
Y
W
4
0.71 ±0.05
= Supplier emblem
= Lot identifier
= Last three numbers of device part number
= Last two digits of year of manufacture
= Week of manufacture
0.60±0.10
+0.06
0.38
–0.04
For Reference Only, not for tooling use (reference DWG-9006)
Dimensions in millimeters
A Dambar removal protrusion (16X)
B Metallic protrusion, electrically connected to pin 4 and substrate (both sides)
24.65 ±0.10
C Thermoplastic Molded Lead Bar for alignment during shipment
D Branding scale and appearance at supplier discretion
10.90 ±0.10
E Active Area Depth, 0.043 mm REF
1.0 REF
F Hall elements (E1 & E2), not to scale
2.00 ±0.10
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
Digure 9: Package SJ, 4-Pin SIP
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
14
ATS468
Three-Wire True Zero-Speed Differential Peak-Detecting
Sensor IC with Continuous Calibration
Revision History
Revision
Current
Revision Date
–
September 29, 2014
Description of Revision
Initial Release
Copyright ©2014, 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 any devices or systems, including but not limited to life support devices or systems, in which a failure of
Allegro’s product can reasonably be expected to cause bodily harm.
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
15