A1699 Datasheet

A1699
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
FEATURES AND BENEFITS
• Integrated IC and capacitor, single overmolded package
to reduce external EMI-protection requirements
• Two-wire, pulse-width output protocol
• Highly configurable output protocol options
• Digital output representing target profile
• Speed and direction information of target
• Vibration tolerance
□□ Small-signal lockout for small amplitude vibration
□□ Proprietary vibration detection algorithms for large
amplitude vibration
• Air-gap-independent switchpoints
• Large operating air gap capability
• Undervoltage lockout
• True zero-speed operation
• Wide operating voltage range
• AEC-Q100 automotive qualified
• Robust test-coverage capability with Scan Path and
IDDQ measurement
Package: 2-Pin SIP (Suffix UB)
DESCRIPTION
The A1699 is an optimized Hall-effect integrated circuit (IC)
that provides a user-friendly solution for direction detection
and true zero-speed, digital ring-magnet sensing. The small
package can be easily assembled and used in conjunction with
a wide variety of target sensing applications.
The IC employs patented algorithms for the special operational
requirements of automotive transmission applications. The
speed and direction of the target are communicated through a
variable pulse-width output protocol. The A1699 is particularly
adept at handling vibration without sacrificing maximum air
gap capability or creating any erroneous direction information.
The advanced vibration detection algorithm will systematically
calibrate the sensor IC on the initial magnetic poles of true
target rotation and not on vibration, always guaranteeing an
accurate signal in running mode.
Advanced signal processing and innovative algorithms make
the A1699 an ideal solution for a wide range of speed- and
direction-sensing needs.
The A1699 is provided in a 2-pin miniature SIP package
(suffix UB) that is lead (Pb) free, with tin leadframe plating.
The UB package includes an IC and capacitor integrated into a
single overmolded package to reduce external EMI protection
requirements.
Not to scale
VCC
Regulator
(Analog)
Regulator
(Digital)
Hall Amp
Offset
Adjust
AGC
Filter
ADC
Synchronous
Digital Controller
Hall Amp
Offset
Adjust
AGC
Filter
Output
Control
ADC
GND
Functional Block Diagram
A1699-DS, Rev. 6
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Complete Part
Number Format
Configuration
A1699 L UB TN -X X X X X -T
Allegro Identifier and Device Type
Operating Temperature Range
Package Designation
Instructions (Packing)
Leadframe Plating
Allegro Identifier and Device Type
[A1699]
Operating Temperature Range
[L]
Package Designation
[UB] 2-pin plastic SIP
Instructions (Packing)
[TN] Tape and reel
Configuration
Rotation Direction
[-F] pin 1-to-2 forward or
[-R] pin 2-to-1 forward
Number of Pulses
[S] single, one pulse per magnetic pole pair or
[D] dual, one pulse for each north and south pole
Reverse Pulse
Width
[N] 90 µs (narrow) or
[W] 180 µs (wide)
Calibration Pulses
[B] Blanked, no output during Calibration or
[P] Pulses during Calibration
Vibration Immunity
/ Direction Change
[L] Low vibration immunity with immediate
direction change detection or
[H] High vibration immunity with non-direction
pulses
Leadframe Plating
[T] Lead (Pb) free
For example: A1699LUBTN-RSNPL-T
Where a configuration character is unspecified, “x” will be used. For example, -xSNPL applies to both
Rotation Direction configuration variants.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
SPECIFICATIONS
SELECTION GUIDE
Part Number
Packing*
A1699LUBTN–xxxxx–T
4000 pieces per 13-in. reel
*Contact Allegro™ for additional packing options.
ABSOLUTE MAXIMUM RATINGS*
Characteristic
Symbol
Supply Voltage
VCC
Reverse Supply Voltage
VRCC
Rating
Unit
28
V
–18
V
–40 to 150
ºC
TJ(max)
165
ºC
Tstg
–65 to 170
ºC
Value (Typ.)
Unit
10000
pF
Operating Ambient Temperature
TA
Maximum Junction Temperature
Storage Temperature
Notes
Refer to Power Derating Section
L temperature range
INTERNAL DISCRETE CAPACITOR RATINGS
Characteristic
Symbol
Nominal Capacitance
CSUPPLY
Test Conditions
Connected between VCC and GND
Terminal List Table
1
Name
Number
Function
VCC
1
Supply Voltage
GND
2
Ground
2
Package UB, 2-Pin SIP Pinout Diagram
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
OPERATING CHARACTERISTICS: Valid throughout full operating and temperature ranges, unless otherwise specified
Characteristic
Symbol
Test Conditions
Min.
Typ.1
Max.
Unit
ELECTRICAL CHARACTERISTICS
Supply Voltage2
Undervoltage Lockout
Reverse Supply Current3
Supply Zener Clamp Voltage
Supply Current
VCC
Operating, TJ < TJ(max)
4
–
24
V
VCC transitioning from 0 → 5 V or 5 → 0 V
–
3.6
3.95
V
VCC = VRCC(max)
–
–
–10
mA3
VZSUPPLY
ICC = ICC(max) + 3 mA, TA = 25ºC
28
–
–
V
ICC(LOW)
Low-current state (running mode)
5
–
8
mA
ICC(HIGH)
High-current state (running mode)
12
–
16
mA
Low-current level (calibration) and Power-on
mode
5
–
8.5
mA
1.9
–
–
–
VCC(UV)
IRCC
ICC(SU)
(LOW)
Supply Current Ratio
ICC(HIGH)/
ICC(LOW)
Measured as a ratio of high current to low
current
OUTPUT
Output Rise Time
tr
ΔI/Δt from 10% to 90% ICC level; Corresponds to
measured output slew rate with CSUPPLY
–
2
4
μs
Output Fall Time
tf
ΔI/Δt from 90% to 10% ICC; Corresponds to
measured output slew rate with CSUPPLY
–
2
4
μs
OUTPUT PULSE CHARACTERISTICS4
Pulse Width, Forward Rotation
Pulse Width, Reverse Rotation
Pulse Width, Non-Direction
tw(FWD)
tw(REV)
tw(ND)
38
45
52
μs
-xxNxx variant
76
90
104
μs
-xxWxx variant
153
180
207
μs
-xxNPx and -xxNxH variants
153
180
207
μs
-xxWPx and -xxWxH variants
306
360
414
μs
Continued on the next page…
VS
1 VCC
CSUPPLY
A1699
2 GND
VOUT
CL
RL
Figure 1: Typical Application Circuit
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
OPERATING CHARACTERISTICS (continued): Valid throughout full operating and temperature ranges, unless otherwise
specified
Characteristic
Symbol
Test Conditions
Min.
Typ.1
Max.
Unit
Operate Point
BOP
% of peak-to-peak IC-processed magnetic signal
–
69
–
%
Release Point
BRP
% of peak-to-peak IC-processed magnetic signal
–
31
–
%
-xSxxx variant
0
–
12
kHz
-xDxxx variant
0
–
6
kHz
-xSNxx variant
0
–
7
kHz
-xDNxx variant
0
–
3.5
kHz
-xSWxx variant
0
–
4
kHz
-xDWxx variant
0
–
2
kHz
-xSNxx variant
0
–
4
kHz
-xDNxx variant
0
–
2
kHz
-xSWxx variant
0
–
2.2
kHz
-xDWxx variant
0
–
1.1
kHz
Magnitude valid for both differential magnetic
channels
–300
–
300
G
Peak to peak differential signal; valid for each
magnetic channel.
30
–
1200
G
-xxxxL variant
TTARGET
–
–
deg.
-xxxxH variant
TTARGET
–
–
deg.
-xxxxL variant
0.12 ×
TTARGET
–
–
deg.
-xxxxH variant
TTARGET
–
–
deg.
–
–0.2
–
%/°C
OPERATING CHARACTERISTICS
Operating Frequency, Forward
Rotation
fFWD
Operating Frequency, Reverse
Rotation5
fREV
Operating Frquency, Non-Direction
Pulses5
fND
DAC CHARACTERISTICS
Allowable User-Induced Offset
PERFORMANCE CHARACTERISTICS
Operational Magnetic Range
BIN
Vibration Immunity (Startup)
ErrVIB(SU)
See Figure 2
Vibration Immunity (Running Mode)
ErrVIB
See Figure 2
Magnetic Temperature Coefficient
TCMAG
Optimized value, for ring magnet
1 Typical
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 representative discussions in Power Derating section.
3 Negative current is defined as conventional current coming out of (sourced from) the specified device terminal.
4 Load circuit is RL = 100 Ω and CL = 10 pF. Pulse duration measured at threshold of ( (I
CC(HIGH) + ICC(LOW)) /2).
5 Maximum Operating Frequency is determined by satisfactory separation of output pulses: I
CC(LOW) of tw(FWD)(MIN). If the customer can resolve shorter low-state durations,
maximum fREV and fND may be increased.
2 Maximum
Target
S
N
S
360º (degrees prime)
N
VSP
T TARGET
VPROC
VPROC(BOP)
TVPROC
VPROC(pk-pk)
VPROC = the processed analog signal of the sinusoidal magnetic input (per channel)
TTARGET = the period between successive sensed target magnetic edges of the same
polarity (either both north-to-south or both south-to-north)
(BOP)
(BRP)
VPROC(BRP)
VSP
VSP(sep) =
VSP
VPROC(pk-pk)
Figure 2: Definition of TTARGET
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
OPERATING CHARACTERISTICS (continued): Valid throughout full operating and temperature ranges, unless otherwise
specified
Characteristic
Symbol
Test Conditions
Min.
Typ.1
Max.
Unit
INPUT MAGNETIC CHARACTERISTICS
Allowable Differential Sequential
Signal Variation
BSEQ(n+1) /
BSEQ(n)
Signal cycle-to-cycle variation (see Figure 3)
0.6
–
–
–
BSEQ(n+i) /
BSEQ(n)
Overall signal variation (see Figure 3)
0.4
–
–
–
BIN > 60 GPP
BIN ≤ 1200 GPP
–
2×
TTARGET
<3 ×
TTARGET
degrees
30 GPP ≤ BIN
BIN ≤ 60 GPP
–
2.5 ×
TTARGET
<4 ×
TTARGET
degrees
-xxxxL variant
–
1
–
switchpoint
-xxxxH variant
1×
TTARGET
2×
TTARGET
3×
TTARGET
degrees
-xxxxL variant
–
–
1.25 ×
TTARGET
degrees
-xxxxH variant
1×
TTARGET
2×
TTARGET
3×
TTARGET
degrees
20
–
–
%
pk-pk
CALIBRATION
First Direction Output
Amount of target rotation
(constant direction) following
power-on until first electrical
output pulse of either tw(FWD)
or tw(REV). See Figure 2
Pulse6
First Direction Pulse Output Following
Direction Change
NCD
Amount of target rotation
(constant direction) following
event until first electrical
output pulse of either tw(FWD)
or tw(REV). See Figure 2
First Direction Pulse Output Following
Running Mode Vibration
Switch Point Separation
6 Power-up
Amount of target rotation
(constant direction) following
event until first electrical
output pulse of either tw(FWD)
or tw(REV). VSP(sep) ≥ 35.
See Figure 2
VSP(sep)
Minimum separation between channels as a
percentage of signal amplitude at each switching
point. See Figure 2
frequencies ≤ 200 Hz. Higher power-on frequencies may require more input magnetic cycles until output edges are achieved.
BSEQ(n)
BSEQ(n + 1)
BSEQ(n+1), i ≥ 2
Figure 3: Differential Signal Variation
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
6
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
THERMAL CHARACTERISTICS
Characteristic
Package Thermal
Resistance
Symbol
Test Conditions*
RθJA
Single-layer PCB with copper limited to solder pads
Value
Unit
213
ºC/W
*Additional thermal information is available on the Allegro website.
Power Derating Curve
26
VCC(max)
Maximum Allowable VCC (V)
24
22
20
18
16
RθJA = 213 °C/W
14
12
10
8
6
VCC(min)
4
2
0
20
40
60
80
100
120
140
160
Ambient Temperature, TA (ºC)
Power Dissipation versus Ambient Temperature
1000
Power Dissipation, PD (mW)
900
800
700
600
500
RθJA = 213 °C/W
400
300
200
100
0
20
40
60
80
100
120
140
160
Ambient Temperature, TA (ºC)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
CHARACTERISTIC PERFORMANCE
Supply Current
18
18
VCC = 4 V
TA = +25ºC
16
16
ICC HIGH
14
SUPPLY CURRENT (mA)
SUPPLY CURRENT (mA)
ICC HIGH
12
10
8
14
12
10
8
6
6
ICC LOW
4
ICC LOW
4
-50
-25
0
25
50
75
100
125
0
150
5
AMBIENT TEMPERATURE (ºC)
10
15
18
25
18
VCC = 24 V
TA = +150ºC
16
16
ICC HIGH
ICC HIGH
14
SUPPLY CURRENT (mA)
SUPPLY CURRENT (mA)
20
SUPPLY VOLTAGE (V)
12
10
8
14
12
10
8
ICC LOW
6
6
4
ICC LOW
4
-50
-25
0
25
50
75
AMBIENT TEMPERATURE (ºC)
100
125
150
0
5
10
15
20
25
SUPPLY VOLTAGE (V)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
8
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Supply Current Ratio
5
Vcc = 4 V
4.5
4.5
4
4
3.5
3.5
SUPPLY CURRENT RATIO
SUPPLY CURRENT RATIO
5
3
2.5
ICC RATIO
2
1.5
3
ICC RATIO
2.5
2
1.5
1
1
0.5
0.5
0
TA = +25°C
0
-50
-25
0
25
50
75
100
125
150
0
5
AMBIENT TEMPERATURE (°C)
15
5
Vcc = 24 V
4.5
4.5
4
4
SUPPLY CURRENT IN MILLIAMPERE
SUPPLY CURRENT IN MILLIAMPERE
5
3.5
3
2.5
10
20
25
SUPPLY VOLTAGE (V)
ICC RATIO
2
1.5
TA = +150°C
3.5
3
ICC RATIO
2.5
2
1.5
1
1
0.5
0.5
0
0
-50
-25
0
25
50
75
AMBIENT TEMPERATURE (°C)
100
125
150
0
5
10
15
20
25
SUPPLY VOLTAGE (V)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
9
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Pulse Width
500
500
Vcc = 4 V
NON DIRECTION (-xxWPx and -xxWxH variants)
400
NON DIRECTION (-xxWPx and -xxWxH variants)
400
350
PULSE WIDTH (µs)
350
PULSE WIDTH (µs)
TA = +25°C
450
450
300
250
REVERSE ( -xxWxx variant )
200
150
250
REVERSE ( -xxNxx variant )
100
FORWARD
50
REVERSE ( -xxWxx variant )
200
150
REVERSE ( -xxNxx variant )
100
300
FORWARD
50
0
0
-50
-25
0
25
50
75
100
125
0
150
5
500
450
20
25
TA = +150°C
450
NON DIRECTION (-xxWPx and -xxWxH variants)
NON DIRECTION (-xxWPx and -xxWxH variants)
400
350
350
PULSE WIDTH (µs)
PULSE WIDTH (µs)
15
500
Vcc = 24 V
400
10
SUPPLY VOLTAGE (V)
AMBIENT TEMPERATURE (°C)
300
250
REVERSE ( -xxWxx variant )
200
150
250
REVERSE ( -xxWxx variant )
200
150
REVERSE ( -xxNxx variant )
100
300
REVERSE ( -xxNxx variant )
100
FORWARD
50
0
-50
-25
0
25
50
FORWARD
50
75
AMBIENT TEMPERATURE (°C)
100
125
150
0
0
5
10
15
20
25
SUPPLY VOLTAGE (V)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
10
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
FUNCTIONAL DESCRIPTION
Sensing Technology
Direction Detection
The sensor IC contains a single-chip Hall-effect circuit that
supports a trio of Hall elements. These elements are used in
differential pairs to provide electrical signals containing information regarding edge position and direction of target rotation. The
A1699 is intended for use with ring magnet and gear targets.
The sensor IC compares the relative phase of its two differential
channels to determine which direction the target is moving. The
relative switching order is used to determine the direction, which
is communicated through the output protocol.
After proper power is applied to the sensor IC, it is capable of
providing digital information that is representative of the magnetic features of a rotating target. The waveform diagrams in
Figure 4 present the automatic translation of the target profiles to
the digital output signal of the sensor IC
Data Protocol Description
When a target passes in front of the device (opposite the branded
face of the package case), the A1699 generates an output pulse(s)
for each pair of magnetic poles of the target. Speed information is
provided by the output pulse rate, while direction of target rotation is provided by the duration of the output pulses. The sensor
IC can sense target movement in both the forward and reverse
directions.
Target
N
Device Orientation to Target
(Pin 2 Side)
(Top View of
Package Case)
E3
Package Case Branded Face
E2
IC
Channel B
Element Pitch
E1
Channel A
Element Pitch
Mechanical Position (Target moves past device pin 1 to pin 2)
Target
(Radial Ring Magnet)
This pole
sensed earlier
N
This pole
sensed later
(Top View of
(Pin 2
Package Case)
Side)
Back-Biasing
Rare-Earth Pellet
B Channel
Target Magnetic Profile
Channel
Element Pitch
+B
E3
IC
ICE2
E1
(Pin 1
Side)
South Pole
Pole Piece
(Concentrator)
A Channel
North Pole
Mechanical Position (Target moves past device pin 1 to pin 2)
N
S
Package Case
Branded Face
Device Orientation to Target
(Pin 1 Side)
This tooth
sensed later
This tooth
sensed earlier
Target Magnetic Profile
Channel
Element Pitch
+B
–B
IC Internal Differential Analog Signals, VPROC
BOP
BOP
A Channel
BOP
IC Internal Differential Analog Signals, VPROC
BOP
A Channel
BRP
BOP
B Channel
BRP
Detected Channel Switching
A Channel
B Channel
BRP
Detected Channel Switching
A Channel
B Channel
B Channel
Device Output Signal
Device Output Signal
I
ICC(High)
I
ICC(Low)
CC(High)
CC(Low)
BRP
Figure 4: The magnetic profile reflects the features of the target, allowing the sensor IC to present an accurate
digital output (-xSxxx variant shown).
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
11
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Forward Rotation (see Figure 5)
When the target is rotating such that a magnetic pole near the
sensor IC (of -Fxxxx variant) passes from pin 1 to pin 2, this is
referred to as forward rotation. This direction is opposite for the
-Rxxxx variant. Forward rotation is indicated by output pulse
widths of tw(FWD) (45 μs typical).
Reverse Rotation (see Figure 5)
When the target is rotating such that a magnetic pole passes from
pin 2 to pin 1, it is referred to as reverse rotation for the -Fxxxx
variant. This direction is opposite for the -Rxxxx variant. Reverse
rotation is indicated by output pulse widths of tw(REV) (90 μs typical for -xxNxx variant, or 180 μs typical for -xxWxx variant).
Timing
As shown in Figure 6, the pulse appears at the output slightly
before the sensed magnetic edge traverses the package branded
face. For targets rotating from pin 2 to 1, this shift (Δfwd with R
variants, with south pole of backbiasing pellet toward IC) results
in the pulse corresponding to the valley with the sensed mechanical edge; for targets rotating from pin 1 to 2, the shift (Δrev)
results in the pulse corresponding to the tooth with the sensed
edge. Figure 7 shows pulse timing for F variants. The sensed
mechanical edge that stimulates output pulses is kept the same for
both forward and reverse rotation by using only one channel to
control output switching.
Direction Validation
For the -xxxxL variant, following a direction change in running mode, direction changes are immediately transmitted to the
output.
For the -xxxxH variant, following a direction change in running
mode, output pulses have a width of tw(ND) until direction information is validated.
Pin 2 to 1 Rotation
Pin 1 to 2 Rotation
N
S
N
S
N
S N
S
N
Output Pulse
(Pin 2 to 1 Rotation)
S
Δrev
tw(REV)
Pin 1
Pin 2
Branded Face
of Sensor
Rotating Target
S
N
S
N
S N
S
N
t
Output Pulse
(Pin 1 to 2 Rotation)
(A) Forward Rotation
N
Tooth
Δfwd
tw(FWD)
Branded Face
of Sensor
Rotating Target
Valley
Figure 6: Output Protocol (-RSxxx variant)
Δrev
tw(REV)
S
Pin 1
Pin 2
(B) Reverse Rotation
Output Pulse
(Pin 2 to 1 Rotation)
Δfwd
tw(FWD)
Figure 5: Target Rotation for -Fxxxx Variant.
-Rxxxx variant inverts detected direction of rotation.
t
Output Pulse
(Pin 1 to 2 Rotation)
Figure 7: Output Protocol (-FDxxx variant)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
12
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Target Rotation Forward
N
S
N
S
Target Rotation Reverse
S
N
S
N
Target
Differential
Magnetic
Profile
tw(REV)
tw(FWD)
tw(FWD)
IOUT
tw(REV)
t
Figure 8: Example Running Mode Direction Change (-FSxxL variant)
Target Rotation Forward
N
S
N
S
Target Rotation Reverse
S
N
S
N
Target
Differential
Magnetic
Profile
IOUT
tw(FWD)
tw(FWD)
tw(ND)
tw(REV)
t
Figure 9: Example Running Mode Direction Change (-FSxxH variant)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
13
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Startup Detection/Calibration
When power is applied to the A1699, the sensor IC internally
detects the profile of the target. The gain and offset of the
detected signals are adjusted during the calibration period, normalizing the internal signal amplitude for the air gap range of the
device.
The Automatic Gain Control (AGC) feature ensures that operational characteristics are isolated from the effects of installation
air gap variation.
Automatic Offset Adjustment (AOA) is circuitry that compensates for the effects of chip, magnet, and installation offsets.
This circuitry works with the AGC during calibration to adjust
VPROC in the internal A-to-D range to allow for acquisition of
signal peaks. AOA and AGC function separately on the two differential signal channels.
Direction information is available after calibration is complete.
For the -xxxBx variant, the output becomes active at the end of
calibration. Figure 10 shows where the first output edges may
occur for various starting target phases.
For the -xxxPx variant, output pulses of tw(ND) are supplied during calibration. Figure 11 shows where the first output edges may
occur for various starting target phases.
Target Rotation
N
S
N
N
S
S
Target
Differential
Magnetic
Profile
ICC
Opposite
north pole
Opposite
N→S boundary
N
S
N
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
Opposite
south pole
Opposite
S→N boundary
t
Device Location at Power-On
Figure 10: Startup Position Effect on First Device Output Switching (-xxxBx variant)
Target Rotation
N
S
N
N
S
Target
Differential
Magnetic
Profile
ICC
Opposite
north pole
Opposite
N→S boundary
N
S
S
N
tW(ND)
tW(ND)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
tW(ND)
tW(ND)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
tW(ND)
tW(ND)
tW(FWD) or
tW(REV)
tW(ND)
tW(ND)
tW(FWD) or
tW(REV)
tW(FWD) or
tW(REV)
Opposite
south pole
Opposite
S→N boundary
t
Device Location at Power-On
Figure 11: Startup Position Effect on First Device Output Switching (-xxxPx variant)
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
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14
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Vibration Detection
Algorithms embedded in the IC’s digital controller detect the
presence of target vibration through analysis of the two magnetic
input channels.
For the -xxxxL variant, the first direction change is immediately
transmitted to the output. During any subsequent vibration, the
output is blanked and no output pulses will occur for vibrations
less than the specified vibration immunity. Output pulses containNormal Target Rotation
N
S
N
Vibration
S
ing the proper direction information will resume when direction
information is validated on constant target rotation.
For the -xxxxH variant, in the presence of vibration, output pulses
of tw(ND) may occur or no pulses may occur, depending on the
amplitude and phase of the vibration. Output pulses have a width
of tw(ND) until direction information is validated on constant
target rotation.
Normal Target Rotation
S
N
S
N
Target
Differential
Magnetic
Profile
t W (FWD)
t W (FWD)
[or t W (REV)]
[or t W (REV)]
t W (REV)
t W (FWD)
t W (FWD)
[or t W (REV)]
[or t W (REV)]
[or t W (FWD)]
t
Figure 12: Output Functionality in the Presence of Running Mode Target Vibration (-xxxxL variant)
Normal Target Rotation
N
S
N
Vibration
S
Normal Target Rotation
S
N
S
N
Target
Differential
Magnetic
Profile
t W (FWD)
t W (FWD)
[or t W (REV)]
[or t W (REV)]
t W (FWD)
t W (FWD)
[or t W (REV)]
[or t W (REV)]
t W (ND)
t W (ND)
t W (FWD)
[or t W (REV)]
t W (ND)
t W (ND)
t W (ND)
t W (FWD)
[or t W (REV)]
t
Figure 13: Output Functionality in the Presence of Running Mode Target Vibration (-xxxxH variant)
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
15
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
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 website.)
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,
UB, 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)
∆T = PD × RθJA (2)
TJ = TA + ∆T (3)
For example, given common conditions such as: TA= 25°C,
VCC = 12 V, RθJA = 213 °C/W, and Icc = 6.5 mA, then:
PD = VCC × ICC = 12 V × 6.5 mA = 78 mW
∆T = PD × RθJA = 78 mW × 213 °C/W = 16.6°C
TJ = TA + ∆T = 25°C + 16.6°C = 41.6°C
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.
Observe the worst-case ratings for the device, specifically:
RθJA = 213°C/W, TJ(max) = 165°C, VCC(max) = 24 V, and ICC(mean)
= 14.8 mA. (Note: For variant -xxWPx, at maximum target
frequency, ICC(LOW) = 8 mA, ICC(HIGH) = 16 mA, and maximum
pulse widths, the result is a duty cycle of 84% and thus a worstcase mean ICC of 14.8 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 ÷ RθJA = 15°C ÷ 213 °C/W (estimated) = 70.4
mW
Finally, invert equation 1 with respect to voltage:
VCC(est) = PD(max) ÷ ICC(max) = 70.4 mW ÷ 14.8 mA = 4.7 V
The result indicates 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.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
16
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
PACKAGE OUTLINE DRAWING
For Reference Only – Not for Tooling Use
(Reference DWG-9070)
Dimensions in millimeters – NOT TO SCALE
Dimensions exclusive of mold flash, gate burs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
4.00 ±0.05
B
4X10°
E 1.45
1.50 ±0.10
1.45 E
C
0.55 E
1.41 E
4.00 ±0.05
E E1
Mold Ejector
Pin Indent
E3 E
E2 E
A
4 X 2.50 REF
0.25 REF
0.30 REF
45°
Branded
Face
NNN
YYWW
LLLL
0.85 ±0.05
0.42 ±0.10
2.54 REF
4 X 0.85 REF
D Standard Branding Reference View
1
N
Y
W
L
2
1.00 ±0.10
= Supplier emblem
= Last three digits of device part number
= Last 2 digits of year of manufacture
= Week of manufacture
= Lot number
12.20 ±0.10
4 X 7.37 REF
+0.05
0.25 –0.03
1.80 REF
A Dambar removal protrusion (8×)
B Gate and tie burr area
C Active Area Depth, 0.38 mm REF
0.38 REF
D Branding scale and appearance at supplier discretion
0.25 REF
4 X 0.85 REF
E Hall elements (E1, E2, and E3); not to scale
0.85 ±0.05
F Molded Lead Bar for preventing damage to leads during shipment
1.80 ±0.05
F
4.00 ±0.05
1.50 ±0.10
Figure 14: Package UB, 2-Pin SIP
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
17
Two-Wire, Differential, Vibration-Resistant
Sensor IC with Speed and Direction Output
A1699
Revision History
Revision
Revision Date
–
March 1, 2014
1
October 7, 2014
2
December 12, 2014
3
March 24, 2015
4
September 23, 2015
5
March 1, 2016
6
April 7, 2016
Description of Revision
Initial release
Updated Package Outline Drawing and reformatted document
Revised CSUPPLY, tr, and tf
Updated branding on Package Outline Drawing
Updated Hall element number and positions in top outline of Package Outline Drawing; updated
Figures 6 and 7 and associated text on page 12; updated Pulse Width Characteristic Performance
plots on page 10; removed bulk offering on page 2-3; additional editorial changes
Updated Package Outline Drawing molded lead bar footnote and Internal Discrete Capacitor
Ratings table.
Corrected Figure 6 and 7 captions.
Copyright ©2016, 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
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
18
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