Allegro A1369 Customer programmable linear hall-effect sensor Datasheet

A1369
Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
FEATURES AND BENEFITS
• Customer programmable offset, and sensitivity
• Sensitivity & QVO temperature coefficients programmed
at Allegro for improved accuracy
• Output value decreases with South Magnetic Field and
increases with North Magnetic field.
• 3-pin SIP package for easy integration with magnetic
concentrator
• Low noise, moderate bandwidth, analog output
• High speed chopping scheme minimizes QVO drift over
temperature
• Temperature-stable quiescent voltage output and
sensitivity
• Precise recoverability after temperature cycling
• Output voltage clamps provide short circuit diagnostic
capabilities
• Under voltage lock-out (UVLO)
Continued on the next page…
Package: 3-Pin SIP (suffix UA)
DESCRIPTION
The Allegro™ A1369 is a customer programmable, high
accuracy linear Hall effect-based current sensor IC. It is
packaged in a thin 3-pin SIP package to allow for easy integration
with a magnetic core to create a highly accurate current sensing
module. The programmable nature of the A1369 enables it
to account for manufacturing tolerances in the final current
sensing module assembly.
This temperature-stable device is available in a through-hole
single in-line package (TO-92). The accuracy of the device
is enhanced via programmability on the output pin for endof-line optimization without the added complexity and cost of
a fully programmable device. The device features One-TimeProgramming (OTP), using non-volatile memory, to optimize
device sensitivity and the quiescent output voltage (QVO)
(output with no magnetic field) for a given application or
circuit. The A1369 also allow for optimized performance over
temperature through programming the temperature coefficient
for both Sensitivity and QVO at Allegro end of line test.
These ratiometric Hall effect sensor ICs provide a voltage
output that is proportional to the applied magnetic field. The
quiescent voltage output is user adjustable around 50% of the
supply voltage and the output sensitivity is programmable
within a range of 8.5 mV/G to 12.5 mV/G for the A1369-10
and 22 mV/G to 26 mV/G for the A1369-24.
Not to scale
Continued on the next page…
Tuned Filter
VCC
Dynamic Offset
Cancellation
V+
Sensitivity and
Sensitivity TC
Offset and
Offset TC
Trim Control
GND
Functional Block Drawing
A1369-DS, Rev. 1
VOUT/
Programming
Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
FEATURES AND BENEFITS (CONTINUED)
• Wide ambient temperature range: -40ºC to +85ºC
• Immune to mechanical stress
DESCRIPTION (CONTINUED)
The features of this linear device makes it ideal for use in industrial
applications requiring high accuracy and are guaranteed over a wide
temperature range, –40°C to+85°C.
Selection Guide
Part Number
Sensitivity Range (mV/G)
A1369EUA-10-T
8.5 to 12.5
A1369EUA-24-T
22 to 26
*Contact Allegro™ for additional packing options.
Functional Block Diagram
Specifications
Absolute Maximum Ratings
Thermal Characteristics
Pin-out Diagram and Terminal List
Electrical Characteristics
Characteristic Definitions
Chopper Stabilization Technique
1
3
3
3
3
4
7
10
Programming Guidelines
11
Programming procedures
13
Overview
Definition of Terms
Mode/Parameter Selection
Try Mode Bitfield Addressing
11
11
13
13
Table of Contents
Fuse Blowing
Locking the Device
Additional Guidelines
14
15
15
Programming Modes
16
Programming State Machine
18
Package Outline Drawing
21
Try Mode
Blow Mode
Read Mode
Initial State
Mode Selection State
Parameter Selection State
Bitfield Addressing State
Fuse Blowing State
16
16
16
19
19
19
19
19
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
2
Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
SPECIFICATIONS
Absolute Maximum Ratings
Rating
Unit
Forward Supply Voltage
Characteristic
Symbol
VCC
8
V
Reverse Supply Voltage
VRCC
–0.1
V
Forward Output Voltage
VOUT
15
V
Reverse Output Voltage
VROUT
Output Source Current
IOUT(SOURCE)
Output Sink Current
IOUT(SINK)
Notes
VOUT to
VCC to VOUT
–0.1
V
2
mA
10
mA
Operating Ambient Temperature
TA
–40 to 85
ºC
Maximum Junction Temperature
TJ(max)
165
ºC
Tstg
–65 to 170
ºC
Storage Temperature
Thermal Characteristics may require derating at maximum conditions, see application information
Characteristic
Package Thermal Resistance
Symbol
Test Conditions*
Value
Unit
RθJA
Package UA, on 1-layer PCB with copper limited to solder pads
165
ºC/W
*Additional thermal information available on the Allegro website.
Pin-out Diagram and Terminal List Table
Terminal List Table
Number
1
2
3
Name
Function
1
VCC
Input power supply; tie to GND with
bypass capacitor
2
GND
Ground
3
VOUT
Output Signal; also used for
programming
Package UA, 3-Pin SIP Pin-out Diagram
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
3
Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
ELECTRICAL CHARACTERISTICS: valid over TA, CBYPASS = 0.1 µF, VCC = 5 V, unless otherwise noted
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
Electrical Characteristics
Supply Voltage
Under-voltage Threshold1
VCC
4.5
5.0
5.5
V
VUVLOHI
TA = 25°C (device power on)
−
−
3
V
VUVLOLOW
TA = 25°C (device power on)
2.5
−
–
V
ICC
No load on VOUT
−
9
12
mA
Power On Time2
tPO
TA = 25ºC, CL(PROBE) = 10 pF
−
60
−
µs
Delay to Clamp3
tCLP
TA = 25ºC, CL = 10 nF
–
30
–
µs
Supply Zener Clamp Voltage
VZ
TA = 25ºC, ICC = 24.5 mA
6
7.3
–
V
Small signal -3 dB
–
7
–
kHz
TA = 25ºC
–
400
–
kHz
TA = 25°C,
Sens = 10.5 mV/G, CL = 1 nF
−
10
–
mV(p-p)
TA = 25°C,
Sens = 24 mV/G, CL = 1 nF
–
24
−
mV(p-p)
TA = 25°C,
No load out VOUT, f <<BWi
−
1.5
−
mG/√Hz
Supply Current
Internal Bandwidth
Chopping Frequency4
BWi
fC
Output Characteristics
Output Referred Noise5
VN
Input Referred Noise Density
VNRMS
DC Output Resistance
ROUT
−
<1
−
Ω
Output Load Resistance
RL
VOUT to GND
4.7
–
–
kΩ
Output Load Capacitance
CL
VOUT to GND
Output Voltage Clamp6
−
–
1
nF
VCLP(HIGH)
TA = 25°C, B = + X G;
RL = 10 kΩ (VOUT to GND)
4.55
–
–
V
VCLP(LOW)
TA = 25°C, B = –X G;
RL = 10 kΩ (VOUT to GND)
–
–
0.45
V
VOUT(Q)init
B = 0 G, TA = 25ºC
−
2.5
–
V
A1369-10, TA = 25°C
–
-10
–
mV/G
A1369-24, TA = 25°C
–
-24
–
mV/G
Initial QVO and Sensitivity
Pre-Programming Quiescent Voltage
Output
Pre-Programming Sensitivity
Sensinit
Target Sensitivity Temperature
Coefficient
TCSens
TA = 85°C, calculated relative to 25°C
–
0
–
%/ºC
ΔVOUT(Q)
TA = 85°C, calculated relative to 25°C
–
0
–
%/ºC
Target Quiescent Voltage Output Drift
Continued on the next page…
1On
power-up, the output of the A1369 will be held low until VCC exceeds VUVLOHI. Once powered, the output will remain valid until VCC drops below VUVLOLO,
when the output will be pulled low
2See Characteristic Definitions
3See Characteristic Definitions
4f varies up to approximately ±20% over the full operating ambient temperature range & process
C
5 Value is derived as 6 sigma value from the spectral noise density.
6V
CLP(LOW) and VCLP(HIGH) will scale with VCC due to ratiometry
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115 Northeast Cutoff
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1.508.853.5000; www.allegromicro.com
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Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
ELECTRICAL CHARACTERISTICS (continued): valid over TA, CBYPASS = 0.1 µF, VCC = 5 V, unless otherwise noted
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
2.45
–
2.55
V
−
5
–
Bits
4.75
7.5
10.5
mV
–
StepVOUT(Q)
× ±0.5
Customer Quiescent Voltage Output Programming
Guaranteed Quiescent Voltage Output
Range7
VOUT(Q)
TA = 25ºC
Quiescent Voltage Output
Programming Bits
Average Quiescent Voltage Output
Step Size8,9
StepVOUT(Q)
Quiescent Voltage Output
Programming Resolution10
ErrPGVOUT(Q) TA = 25ºC
TA = 25ºC
Customer Sensitivity Programming
Sensitivity Programming Bits
Default Sensitivity
Sens
Guaranteed Fine Step Sensitivity
Range11
Sens
Average Sensitivity Step Size8,9
StepSens
Sensitivity Programming Resolution10
–
7
–
Bits
−
-10.5
−
mV/G
A1369-24, TA = 25ºC
−
-24
−
mV/G
A1369-10, TA = 25ºC
-8.5
–
-12.5
mV/G
A1369-24, TA = 25ºC
-22
–
-26
mV/G
A1369-10, TA = 25ºC
-72
-102
-133
µV/G
A1369-24, TA = 25ºC
-163
-233
-303
µV/G
–
StepSens
× ±0.5
–
µV/G
–
1
–
Bit
A1369-10, TA = 25ºC
ErrPROGSENS TA = 25ºC
Customer Clamp Disable Programming
Clamp Disable Bit
Output
Voltage12
VSAT,HIGH
B = -X G;
RL = 4.7 kΩ (VOUT to GND)
4.75
–
–
V
VSAT,LOW
B = + X G;
RL = 4.7 kΩ (VOUT to GND)
–
–
0.25
V
–
1
–
Bit
Customer Lock
Overall Programming Lock Bit
LOCK
Continued on the next page…
7V
OUT(Q)(max) is the value available with all programming fuses blown (maximum programming code set). VOUT(Q) is the total range from VOUT(Q)init up to and including VOUT(Q)(max). See Characteristic Definitions.
8Step size is larger than required to account for manufacturing spread. See Characteristics Definitions
9Non-ideal behavior in the programming DAC can cause the step size at each significant bit rollover code to be twice the maximum specified value of StepV
OUT(Q) or
StepSENS
10Fine programming value accuracy. See Characteristic Definitions
11Sens
(max) is the value available with all programming fuses blown (maximum programming code set). Sens range is the total range from Sensinit up to and including
Sens(max). See Characteristic Definitions.
12 V
SAT,HIGH and VVSAT,LOW will scale with the supply voltage due to the Ratiometry of the part
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115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
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Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
ELECTRICAL CHARACTERISTICS (continued): valid over TA, CBYPASS = 0.1 µF, VCC = 5 V, unless otherwise noted
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
Error Components13
Linearity Sensitivity Error
Symmetry Sensitivity Error
Ratiometry Quiescent Voltage Output
Error14
Ratiometry Sensitivity Error
Ratiometry Clamp Error
LinERR
SymERR
RatVOUT(Q)
RatSENS
RatVOUTVLP
A1369-10
−
±1.0
−
%
A1369-24
–
±1.5
–
%
A1369-10
−
±1.5
−
%
A1369-24
–
±1.7
–
%
A1369-10, over guaranteed supply
voltage (relative to VCC = 5 V)
−
±0.5
−
%
A1369-24, over guaranteed supply
voltage (relative to VCC = 5 V)
–
±0.5
–
%
A1369-10, over guaranteed supply
voltage (relative to VCC = 5 V)
−
±1.0
−
%
A1369-24, over guaranteed supply
voltage (relative to VCC = 5 V)
–
±1.0
–
%
A1369-10, over guaranteed supply
voltage (relative to VCC = 5 V), TA =
25ºC
−
±0.5
−
%
A1369-24, over guaranteed supply
voltage (relative to VCC = 5 V), TA =
25ºC
–
±0.5
–
%
Additional Characteristics15
Guaranteed Quiescent Voltage Output
Drift Through Temperature Range
ΔVOUT(Q)
Sensitivity Drift Through Temperature
Range
ΔSensTC
Sensitivity Drift Due to Package
Hysteresis
ΔSensPKG
A1369-10, TA = 85°C
−20
−
+20
mV
A1369-24, TA = 85°C
−30
−
+30
mV
A1369-10, TA = -40°C
–
±40
–
mV
A1369-24, TA = -40°C
–
±50
–
mV
A1369-10, measured at 85°C,
calculated relative to 25°C
−
±1.6
−
%
A1369-24, measured at 85°C,
calculated relative to 25°C
TA = 25°C; after temperature cycling
±1.8
−
±2
%
−
%
Typical error is based on ±3 σ value of sample distribution.
change from actual value at VCC = 5 V for a given temperature
15 Typical error is based on ±3 σ value around mean value of sample distribution.
12
13 Percent
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115 Northeast Cutoff
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Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
CHARACTERISTIC DEFINITIONS
Power On Time. When the supply is ramped to its operating voltage, the device output requires a finite time to react to
an input magnetic field. Power On Time is defined as the time
it takes for the output voltage begin responding to an applied
magnetic field after the power supply has reached its minimum
specified operating voltage, VCC(min).
Delay to Clamp. A large magnetic input step may cause the
clamp to overshoot its steady state value. The delay to clamp is
defined as the time it takes for the output voltage to settle within
1% of its steady state value after initially passing through its
steady state voltage.
Magnetic Input
V
VCLP,HIGH
VCC
VCC(typ.)
VOUT
t1
VCC(min.)
tPO
t1
tCLP
Sensor Output
t2
VOUT
90% VOUT
t2
t1 = time at which power supply reaches
minimum specified operating voltage
t1 = time at which output voltage initially
reaches steady state clamp voltage
t2 = time at which output voltage settles
within ±10% of its steady state value
under and applied magnetic field
t2 = time at which output voltage settles to
within ±1% of steady state clamp voltage
0
time (µs)
+t
Figure 1: Power On Time
Guaranteed Quiescent Voltage Output Range. The quiescent
voltage output can be programmed around 2.5 V within the guaranteed quiescent voltage range limits, VOUT(Q)(max) and VOUT(Q)
(min). The available guaranteed programming range falls within
the distribution of initial VOUT(Q) and the max code VOUT(Q).
VOUT(Q)init(typ)
range.
range.
2N
Figure 3: Delay to Clamp
– 1 is the value of the max programming code in the
Quiescent Voltage Output Programming Resolution. The
programming resolution for any device is half of its programming
step size. Therefore the typical programming resolution will be:
0.5 × StepVOUT(Q)(typ)
Garanteed VOUT(Q)
Programming Range
Initial VOUT(Q)
Distribution
VOUT(Q)(min)
Max Code
VOUT(Q) Distribution
VOUT(Q)(max)
Figure 2: QVO Range
Average Quiescent Voltage Output Step Size. The average quiescent voltage output step size for a single device is determined
using the following calculation:
N
StepVOUT(Q) –
VOUT(Q)(2 – 1) – VOUT(Q)init
N
2 –1
where N is the number of available programming bits in the trim
Quiescent Voltage Output Drift Through Temperature Range.
Due to internal component tolerances and thermal considerations the quiescent voltage output, ΔVOUT(Q), may drift from its
nominal value over the operating ambient temperature, TA. For
purposes of specification, the Quiescent Voltage Output Drift
Through Temperature Range, ΔVOUT(Q) (mV), is defined as:
ΔVOUT(Q) = VOUT(Q, TA) – VOUT(Q, 25ºC)
Sensitivity. The presence of a south-pole magnetic field perpendicular to the branded surface of the package face increases the
output voltage from its quiescent value toward the supply voltage
rail. The amount of the output voltage increase is proportional
to the magnitude of the magnetic field applied. Conversely, the
application of a north pole will decrease the output voltage from
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Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
its quiescent value. This proportionality is specified as the magnetic sensitivity, Sens (mV/G), of the device and is defined as:
Sens =
VOUT(B+) – VOUT(B–)
B+ – B–
sensitivity temperature coefficient effects cause the magnetic
sensitivity to drift from its ideal value over the operating ambient temperature, TA. For purposes of specification, the sensitivity
drift through temperature range, ΔSensTC, is defined:
SensTC –
where B+ and B- are two magnetic fields with opposite polarities.
Guaranteed Sensitivity Range. The magnetic sensitivity can be
programmed around its nominal value within the sensitivity range
limits, Sens(max) and Sens(min). Refer to the section on guaranteed
quiescent voltage output range for a conceptual explanation.
Average Sensitivity Step Size. Refer to the section on average
quiescent voltage output step size for a conceptual explanation.
Sensitivity Programming Resolution. Refer to the section on
quiescent voltage output programming resolution for a conceptual
explanation.
Sensitivity Temperature Coefficient. The device sensitivity
changes over temperature with respect to its sensitivity temperature coefficient, TCSENS. TCSENS is programmed at 85ºC,
and calculated relative to the nominal sensitivity programming
temperature of 25ºC. TCSENS (%/ºC) is defined as:
TCSENS =
( SensSens– Sens
T2
T1
T1
)(T2 –1 T1 )
× 100%
where T1 is the nominal Sens programming temperature of 25ºC,
and T2 is the TCSENS programming temperature of 85ºC.
The ideal value of sensitivity over temperature, SensIDEAL(TA), is
defined as:
Sensitivity Drift Due to Package Hysteresis. Package stress
and relaxation can cause the device sensitivity at TA = 25ºC to
change during/after temperature cycling. This change in sensitivity follows a hysteresis curve. For purposes of specification, the
sensitivity drift due to package hysteresis, ΔSensPKG, is defined:
SensPKG =
Average Sensitivity Temperature Coefficient Step Size. Refer
to the section on average quiescent voltage output step size for a
conceptual explanation.
Sensitivity Temperature Coefficient Programming Resolution. Refer to the section on quiescent voltage output programming resolution for a conceptual explanation.
( Sens Sens– Sens ) × 100%
(25ºV, 2)
(25ºC, 1)
(25ºC, 1)
where Sens(25ºC ,1) is the programmed value of sensitivity at TA =
25ºC, and Sens(25ºC ,2) is the value of sensitivity at TA = 25ºC after
temperature cycling TA up to 85ºC, down to – 40ºC, and back to
up 25ºC.
Linearity Sensitivity Error. The A1369 is designed to provide
linear output in response to a ramping applied magnetic field.
Consider two magnetic fields, B1 and B2. Ideally the sensitivity
of a device is the same for both fields for a given supply voltage
and temperature. Linearity error is present when there is a difference between the sensitivities measured at B1 and B2.
Linearity Error is calculated separately for the positive (LinERR+)
and negative (LinERR-) applied magnetic fields. Linearity error
(%) is measured and defined as:
× 100%
( Sens
Sens )
Sens
= (1 –
× 100%
Sens )
B++
LinERR+ = 1 –
SensIDEAL(TA) = SensT1 × (100% + TCSENS(TA – T1))
Guaranteed Sensitivity Temperature Coefficient Range. The
magnetic sensitivity temperature coefficient can be programmed
within its limits of TCSens(max) and TCSens(min). Refer to the section on guaranteed quiescent voltage output range for a conceptual explanation.
SensTA – SensIDEAL(TA)
× 100%
SensIDEAL(TA)
B+
LinERR-
B--
B-
LinERR = max(|LinERR+|,|LinERR-|)
where
SensBx =
( |V
OUTBx
)
– VOUT(Q)|
Dx
and B++, B+, B--, and B- are positive and negative magnetic fields
with respect to the quiescent voltage output such that |B++| > |B+|
and |B--| > |B-|.
Sensitivity Drift Through Temperature Range. Second order
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Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
The output voltage clamps, VCLP(HIGH) and VCLP(LOW), limit the
operating magnetic range of the applied field in which the device
provides a linear output. The maximum positive and negative
applied magnetic fields in the operating range can be calculated:
|BMAX(+)| –
VCLP,HIGH – VOUT(Q)
Sens
|BMAX(–)| –
VOUT(Q) – VCLP,LOW
Sens
Sens(B+)
Sens(B–)
(
) × 100%
where
SensBx =
(
Sens(VCC) / Sens(5 V)
× 100%
VCC /5 V
RATVOUTCLP = 1 –
Symmetry error, SymERR (%), is measured and defined as:
(
)
(
RATERRSens = 1 –
The ratiometric error in the clamp voltages, RatVOUTCLP (%), for
a given supply voltage, VCC, is defined as:
Symmetry Sensitivity Error. The magnetic sensitivity of a
device is constant for any two applied magnetic fields of equal
magnitude and opposite polarities.
SymERR = 1 –
The ratiometric error in magnetic sensitivity, RatSens (%), for a
given supply voltage, VCC, is defined as:
)
|VOUT(BX) – VOUT(Q)|
Bx
and B+, B- are positive and negative magnetic fields such that
|B+| = |B-|.
Ratiometry Error. The A1369 provides a ratiometric output.
This means that the quiescent voltage output, VOUT(Q), magnetic
sensitivity, Sens, and clamp voltage, VCLP(HIGH) and VCLP(LOW),
are proportional to the supply voltage, VCC. In other words, when
the supply voltage increases or decreases by a certain percentage, each characteristic also increases or decreases by the same
percentage. Error is the difference between the measured change
in the supply voltage relative to 5 V, and the measured change in
each characteristic.
)
VCLP(VCC) / VCLP(5 V)
× 100%
VCC /5 V
where VCLP is either VCLP(HIGH) or VCLP(LOW).
Undervoltage Lockout. The A1369 features an undervoltage
lockout feature that ensures that the device will output a valid signal when VCC is above certain threshold VUVLOHI, and remains
valid until VCC falls below a lower threshold, VUVLOLOW. The
undervoltage lockout feature provides a hysteresis of operation to
eliminate indeterminate output states.
The output of the A1369 is held low (GND) until VCC exceeds
VUVLOHI. Once VCC exceeds VUVLOHI, the device powers
up, and the output will provide a ratiometric output voltage
proportional to the input magnetic signal, and VCC. If VCC
should drop back down below VUVLOLOW for more than tuvlo
after the device is powered up, the output will be pulled low.
VCC
VUVLOHI
VUVLOLOW
VOUT
The ratiometric error in quiescent voltage output, RatVOUT(Q)
(%), for a given supply voltage, VCC, is defined as:
(
RATERRVOUT(Q) = 1 –
)
VOUTO(VCC) / VOUTO(5 V)
× 100%
VCC /5 V
Figure 4: UVLO Operation
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9
Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
A1369
VCC
+
–
5V
0.1 µF
A1369
GND
VOUT
Figure 5: Typical Application Circuit
Chopper Stabilization Technique
When using Hall-effect technology, a limiting factor for switch
point accuracy is the small signal voltage developed across the
Hall element. This voltage is disproportionally small relative to
the offset that can be produced at the output of the Hall sensor.
This makes it difficult to process the signal while maintaining an
accurate, reliable output over the specified operating temperature
and voltage ranges. Chopper stabilization is a unique approach
used to minimize Hall offset on the chip. Allegro employs a
patented technique to remove key sources of the output drift
induced by thermal and mechanical stresses. This offset reduction
technique is based on a signal modulation-demodulation process.
The undesired offset signal is separated from the magnetic fieldinduced signal in the frequency domain, through modulation.
The subsequent demodulation acts as a modulation process for
the offset, causing the magnetic field-induced signal to recover
its original spectrum at base band, while the dc offset becomes
a high-frequency signal. The magnetic-sourced signal then can
pass through a low-pass filter, while the modulated dc offset is
suppressed. In addition to the removal of the thermal and stress
related offset, this novel technique also reduces the amount of
thermal noise in the hall sensor while completely removing the
modulated residue resulting from the chopper operation. The
chopper stabilization technique uses a high frequency sampling
clock. For demodulation process, a sample and hold technique is
used. This high-frequency operation allows a greater sampling
rate, which results in higher accuracy and faster signal-processing
capability. This approach desensitizes the chip to the effects
of thermal and mechanical stresses, and produces devices that
have extremely stable quiescent Hall output voltages and precise
recoverability after temperature cycling. This technique is made
possible through the use of a BiCMOS process, which allows the
use of low-offset, low-noise amplifiers in combination with highdensity logic integration and sample-and-hold circuits.
Regulator
Clock/Logic
Hall Element
AMP
Anti-aliasing Tuned Filter
LP-Filter
Figure 6: Concept of Chopper Stabilization Technique
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A1369
Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
PROGRAMMING GUIDELINES
Overview
Definition of Terms
Programming is accomplished by sending a series of input voltage pulses serially through the VOUT pin of the device. A unique
combination of different voltage level pulses controls the internal
programming logic of the device to select a desired programmable parameter and change its value. There are three voltage levels
that must be taken into account when programming. These levels
are referred to as high (VPH), mid (VPM), and low (VPL).
Register. The section of the programming logic that controls the
choice of programmable modes and parameters.
The A1369 features a Try mode, Blow mode, and Read mode:
• In Try mode, the value of multiple programmable parameters
may be set and measured simultaneously. The parameter
values are stored temporarily, and reset after cycling the
supply voltage.
• In Blow mode, the value of a single programmable parameter
may be permanently set by blowing solid-state fuses
internal to the device. Additional parameters may be blown
sequentially. This mode is used for blowing the device-level
fuse, which permanently blocks the further programming of all
parameters. Device locking is also accomplished in this mode.
• In Read mode, the current state of the programming fuses can
be read back for verification of programmed value.
The programming sequence is designed to help prevent the device
from being programmed accidentally; for example, as a result
of noise on the supply line. Although any programmable variable power supply can be used to generate the pulse waveforms,
Allegro highly recommends using the Allegro Sensor Evaluation
Kit, available on the Allegro Web site On-line Store. The manual
for that kit is available for
Bit Field. The internal fuses unique to each register, represented
as a binary number. Incrementing the bit field of a particular
register causes its programmable parameter to change, based on
the internal programming logic.
Key. A series of mid-level voltage pulses used to select a register,
with a value expressed as the decimal equivalent of the binary
value. The LSB of a register is denoted as key 1, or bit 0.
Code. The number used to identify the combination of fuses
activated in a bit field, expressed as the decimal equivalent of the
binary value. The LSB of a bit field is denoted as code 1, or bit 0.
Addressing. Incrementing the bit field code of a selected register
by serially applying a pulse train through the VCC pin of the
device. Each parameter can be measured during the addressing
process, but the internal fuses must be blown before the programming code (and parameter value) becomes permanent.
Fuse Blowing. Applying a high voltage pulse of sufficient
duration to permanently set an addressed bit by blowing a fuse
internal to the device. Once a bit (fuse) has been blown, it cannot
be reset.
Blow Pulse. A high voltage pulse of sufficient duration to blow
the addressed fuse.
Cycling the Supply. Powering-down, and then powering-up the
supply voltage. Cycling the supply is used to clear the programming settings in Try mode.
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Customer Programmable Linear Hall-Effect Sensor
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A1369
Table 1: Programming Pulse Requirements
Part Number
Characteristic
Symbol
Test Conditions
Limits
Min.
Typ.
Max.
Units
VPL
4.5
–
5.5
V
VPM
12.5
13
13.5
V
VPH
18
18.5
19
V
200
–
–
m
Programming Protocol (TA = +25ºC)
Programming
Voltage23
Programming Current24
A1369
IP
CBLOW = 0.1 µF
tLOW
20
–
–
µ
tACTIVE27
20
–
–
µ
tBLOW28
90
100
–
µ
Pulse Rise Time
t29
5
–
100
µ
Pulse Fall Time
t30
5
–
100
µ
Blow Pulse Slew Rate
SRBLOW
0.375
–
–
V/µs
26
Pulse Width
23Programming
voltages are measured at the VOUT pin of the package.
supply current available during programming to ensure proper fuse blowing.
25A minimum capacitance, C
BLOW, of 0.1 µF must be connected from VOUT to GND of the SIP during programming to provide the current necessary to blow a fuse.
26Duration of V time between bits.
PL
27V and V
PL
PH durations required during register selection and bit field addressing sequences.
28Pulse duration required to permanently blow a fuse/
29Rise time required for programming voltage transitions from V to V
PL
PM or VPL to VPH.
30Fall time required for programming voltage transitions from V
PM to VPL or VPH to VPL.
24Minimum
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Customer Programmable Linear Hall-Effect Sensor
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A1369
PROGRAMMING PROCEDURES
Mode/Parameter Selection
□□ Accessible only in READ MODE
Each programmable mode/parameter can be accessed through a
specific register. To select a register, a sequence of voltage pulses
consisting of a VPH pulse, a series of VPM pulses, and a VPH pulse
(with no VCC supply interruptions) must be applied serially to
the VOUT pin. The number of VPM pulses is called the key, and
uniquely identifies each register. The pulse train used for selection of the first register, key 1, is shown in Figure 7.
V+
• Register 4:
□□ Margin Low
□□ Margin Comparator
□□ Margin High
□□ Overall Lock Bit
□□ (LOCK)
Try Mode Bitfield Addressing
In Try Mode, after a programmable parameter has been selected,
a VPH pulse transitions the programming logic into the bitfield
addressing state. A series of VPM pulses to the VOUT pin of
the device, as shown in Figure 8, increments the bitfield of the
selected parameter.
VP(HIGH)
VP(MID)
VP(LOW)
tLOW
tACTIVE
0
Figure 7: Parameter Selection Pulse Train
The A1369 has three registers that select among the three programmable modes:
• Register 1:
When addressing the bitfield in Try Mode, the number of
VPM pulses is represented by a decimal number called a code.
Addressing activates the corresponding fuse locations in the
given bitfield by incrementing the binary value of an internal
DAC. The value of the bit field (and code) increments by one
with the falling edge of each VPM pulse, up to the maximum possible code (see the Programming Logic table). As the value of the
bitfield code increases, the value of the programmable parameter
changes. Measurements can be taken after each pulse to determine if the desired result for the programmable parameter has
been reached. Cycling the supply voltage resets all the locations
in the bitfield that have unblown fuses to their initial states.
V+
• Register 3:
□□ READ
VP(MID)
Code 2n – 1
□□ TRY
Code 2
VP(HIGH)
Code 1
• Register 2:
Code 2n – 2
□□ BLOW/LOCK
And three registers that select among the seven programmable
parameters:
• Register 1:
VP(LOW)
□□ Sensitivity (SENS)
• Register 2:
□□ Quiescent Voltage Output (QVO)
• Register 3:
□□ Temperature compensation at Factory
0
Figure 8: Try Mode Bit Field Addressing Pulse Train
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Customer Programmable Linear Hall-Effect Sensor
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Fuse Blowing
After the required code is found for a given parameter, its value
can be set permanently by blowing individual fuses in the appropriate register bit field. Blowing is accomplished by applying
a VPH pulse, called a blow pulse, of sufficient duration at the
VPH level to permanently set an addressed bit by blowing a fuse
internal to the device. Due to power requirements, the fuse for
each bit in the bit field must be blown individually. The A1369
has built in circuitry that will only allow one fuse to be blown at
a time. During blow mode, the bit field can be considered a “onehot” shift register. Table 2 illustrates how to relate the number of
VPM pulses to the binary and decimal value for Blow Mode bit
field addressing. It should be noted that the simple relationship
between the number of VPM pulses and the desired code is:
2n = Code
where n is the number of VPM pulses, and the bit field has an
initial state of decimal code 1 (binary 000000001).
To correctly blow the desired fuses, the code representing the
desired parameter value must be translated to a binary number.
For example, as shown in Figure 9, decimal code 5 is equivalent
to the binary number 101. Therefore bit 2 must be addressed and
blown, the device power supply cycled, and then bit 0 must be
addressed and blown. An appropriate sequence for blowing code
4 is shown in Figure 10. The order of blowing bits, however, is
not important. Blowing bit 0 first, and then bit 2 is acceptable.
Note:
After blowing, the programming is not reversible, even after cycling the supply power. Although
a register bitf ield fuse cannot be reset after it is
blown, additional bits within the same register can
be blown at any time until the device is locked. For
example, if bit 1 (binary 10) has been blown, it is
still possible to blow bit 0. The end result would be
binary 11 (decimal code 3).
Bitfield Selection
Address Code Format
(Decimal Equivalent)
Code 5
Code in Binary
(Binary)
1 0 1
Fuse Blowing
Target Bits
Bit 2
Fuse Blowing
Address Code Format
Bit 0
Code 4
Code 1
(Decimal Equivalents)
Figure 9: Example of Code 5 Broken Into Its Binary
Components, which are Code 4 and Code 1
Table 2: Blow Mode Bitf ield Addressing
# of VPM Pulse
(decimal)
Binary Register
Equivalent Code
(2n)
0
000000001
1
1
000000010
2
2
000000100
4
3
000001000
8
4
000010000
16
5
000100000
32
6
001000000
64
7
010000000
128
8
100000000
256
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Customer Programmable Linear Hall-Effect Sensor
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A1369
Locking the Device
• The application capacitance, CL, should be used when
measuring the output duty cycle during programming.
The blowing capacitor, CBLOW, should be removed during
measurement and should only be applied when blowing fuses.
After the desired code for each parameter is programmed, the
device can be locked to prevent further programming of any
parameters.
Additional Guidelines
• The power supply used for programming must be capable of
delivering at least 18 V and 175 mA.
The additional guidelines in this section should be followed to
ensure the proper behavior of these devices:
• Be careful to observe the tLOW delay time before powering
down the device after blowing each bit.
• A 0.1 μF blowing capacitor, CBLOW, must be mounted between
the VOUT pin and the GND pin during programming, to
ensure enough current is available to blow fuses.
The following programming order is required:
• Sens
• QVO
• The CBLOW blowing capacitor must be replaced in the final
application with the load capacitor, CL, for proper operation.
• LOCK (only after all other parameters have been programmed
and validated, because this prevents any further programming
of the device)
VP(HIGH)
VP(MID)
1
1
2
1
2
Mode Selection
(Key 1)
Parameter Selection
(Key 2)
Addressing Code 4
(Bit 3)
{
VP(LOW)
tBLOW
Cycle VCC
0
Figure 10: Example of Blow Mode Programming Pulses Applied to the VOUT Pin.
In this example, Sensitivity (Parameter Key 1) is addressed to blow bit 3.
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Customer Programmable Linear Hall-Effect Sensor
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A1369
PROGRAMMING MODES
Try Mode
make its value permanent. To do this, select the required parameter register, and address and blow each required bit separately
(as described in the Fuse Blowing section). The supply must be
cycled between blowing each bit of a given code. After a bit is
blown, cycling the supply will not reset its value.
Try mode allows multiple programmable parameters to be tested
simultaneously without permanently setting any values. In this
mode, each high pulse will indefinitely loop the programming
logic through the mode, register, and bit field states. There must
be no interruptions in the VCC supply.
Read Mode
After powering the VCC supply, select mode key 1, the desired
parameter register, and address its bit field. When addressing the
bit field, each VPM pulse increments the value of the parameter
register up to the maximum possible code (see Programming
Logic section). The addressed parameter value will be stored in
the device even after the programming drive voltage is removed
from the VOUT pin, allowing its value to be measured. To test
an additional programmable parameter in conjunction with the
original, enter an additional VPH pulse on the VOUT pin to reenter the parameter selection field. Select a different parameter
register, and address its bit field without any supply interruptions.
Both parameter values will be stored and can be measured after
removing the programming drive voltage. Multiple programming
combinations can be tested to achieve optimal application accuracy. See Figure 11 for an example of the Try Mode pulse train.
The state of the internal fuses can be read at any time in Read
Mode. Read Mode is available before, and after locking the
device. Read mode allows the programmer to verify that the
intended bits were blown.
Registers can be addressed and re-addressed an indefinite number
of times in any order. Once the desired code is found for each
register, cycle the supply and blow the bit field using blow mode.
Note that for accurate time measurements the blow capacitor,
CBLOW, should be removed during output voltage measurement.
Blow Mode
After the required value of the programmable parameter is found
using Hold/Try mode, the corresponding code should be blown to
After power the VCC supply, select mode key 3, the desired
parameter register, and address its bit field. Upon completing the
selection of mode key 3, ICC will increase by 250 µA to indicate
the device is in read fuse mode. On the falling edge of the VPH
pulse that terminates the register selection, ICC will increase by
another 250 µA (total of 500 µA above normal ICC) to indicate
a fuse is blown, or decrease by 250 µA (total of 0 µA above
nominal ICC) to indicate an un-blown fuse. On each consecutive
falling edge of VP\M pulses the A1369 will modify ICC to indicate
the state of each fuse (500 µA above ICC for a blown fuse, and 0
µA above ICC for an un-blown fuse).
The read mode indicates the fuse values of the selected register
in a serial fashion where one bit is read at a time. The LSB (B0)
is selected on the falling edge of the VPH pulse that terminates
the key parameter selection, and begins the addressing code. The
successive VPM pulses select the succeeding bits in this order:
B1, B2, B3, B4, B5, B6, B7, B8. See Figure 12 for an example
pulse train.
VP(HIGH)
VP(MID)
1
2
1
2
1
2
VP(LOW)
Mode Selection
(Key 2)
Parameter Selection
(Key 2)
Next
Parameter
Addressing Code 2
(Bit 1)
0
Figure 11: Example of Try Mode Programming Pulses Applied to the VOUT Pin.
In this example, Sensitivity (Parameter Key 1) is addressed to code 3 and QVO (Parameter Key 2) is addressed to code 2.
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Customer Programmable Linear Hall-Effect Sensor
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A1369
Mode Selection
(Key 3)
Parameter Selection
(Key 2)
Bitfield Addressing
VOUT
VP(HIGH) VP(MID)
VP(LOW)
1
2
3
1
2
0
1
2
3 ...
0
ICC + 500 µA
ICC
ICC + 250 µA
B0 = 1
B2 = 1
ICC
B1 = 0
B2 = 0
Figure 12: Example of Read Mode Programming Pulses Applied to the VOUT Pin and Device Response in ICC.
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Customer Programmable Linear Hall-Effect Sensor
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A1369
PROGRAMMING STATE MACHINE
Powerup
VPM
Initial
VPH
VPH
Mode Select
VPM
VPM
1
Blow/Lock
VPM
VPM
2
Try
3
Read
2 × VPH
2 × VPH
VPH
VPM
VPM
1
Sens
VPM
VPM
2
QVO*
3
TC trim
Lock
VPH
VPH
VPH
VPH
VPM
User Power-down
Required
Selected
Mode?
Try Key 1-3
Code Select
VPM
VPM
1
(Bitfield 0)
VPM
Blow Key 1-4
Try Key 4
Read Key 1-4
VPM
3
(Bitfield 1
and 2)
VPM
2n - 1
n = bits in
register
VPH
VPH
VPH
VPH
Blow
Fuse
2
(Bitfield 1)
Code Select
Code 1
(Bitfield 0)
20
VPH
VPM
VPM
Code 2
(Bitfield 1)
21
VPH
VPM
Code 4
(Bitfield 2)
22
VPH
VPM
Code 8
(Bitfield 3)
23
VPH
VPM
Code 2n
(Bitfield n)
n = bits in
register
VPH
Recommended Repeat Blown Sequence for Final Memory Lock
Figure 13: Programming State Machine
* QVO parameter needs to be programmed last; otherwise, next high pulse will lead to unwanted output polarity change.
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A1369
Customer Programmable Linear Hall-Effect Sensor
Optimized for Use in Current Sensing Applications
Initial State
• 3 pulses – Factory use only
After system power-up, the programming logic is reset to a
known state. This is referred to as the Initial state. All the bit
field locations that have intact fuses are set to logic 0. While in
the Initial state, any VPM pulses on the VOUT pin are ignored.
To enter the Mode Selection state, apply a single VPH pulse on
VOUT pin..
• 4 pulses – Margin Low, Margin comp, margin high, Lock All
Mode Selection State
This state allows the selection of the mode register containing the
parameter to be programmed. To select a mode register, increment through the keys by sending VPM pulses on the VOUT pin.
Register keys select among the following programmable modes:
• 1 pulses –Blow/Lock
• 2 pulses – Try
• 3 pulses – Read
To enter the Parameter Selection state, apply 2 VPH pulses on
VOUT pin.
Parameter Selection State
This state allows the selection of the parameter register containing the bit fields to be programmed.
Applying a VPM pulse to the VOUT pin will increment through
the parameter registers.
• 1 pulse – Sensitivity
• 2 pulses – QVO, Polarity
To enter the Bit Field Addressing state, send one VPH pulse on the
VOUT pin.
Bitfield Addressing State
This state allows the selection of the individual bit fields to be
programmed in the selected parameter register (see Programming
Logic table). Applying VPM pulses to the VOUT pin increments
the bitfield.
In Try Mode, to re-enter the Parameter Selection state send one
VPH pulse on the VOUT pin. The previously addressed parameter
will retain its value as long as VCC is not cycled.
In Blow/Lock Mode, to leave the Bit Field Addressing state
requires either cycle device power or blowing the fuses for the
selected code. Note that merely addressing the bit field does not
permanently set the value of the selected programming parameter; fuses must be blown to do so. In blow mode, only one bit is
active at a time.
Fuse Blowing State
To blow an addressed bit field, apply a VPH pulse on the VOUT
pin. Power to the device should then be cycled before additional
programming is attempted.
Note:
Each bit representing a decimal code must be
blown individually (see the Fuse Blowing section).
Final memory lock will be executed in two steps:
1. Blowing the “Lock All” bit
2. Repeating the programming blow sequence for any bit of
choice. This sequence will not blow that bit; rather, it will
blow the final memory fuse.
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Customer Programmable Linear Hall-Effect Sensor
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A1369
Table 3: Programming Logic16
Programmable Mode
(Register Key)
Bitfield Address
Description
Binary Format
[MSB → LSB]
Decimal Equivalent
Code
Blow/Lock
(1)
01
1
Try
(2)
10
2
Try
Read
(3)
11
3
Read
Registry Selection
Key
Binary Bitfield Address
[MSB → LSB]
Decimal Equivalent
Code
Description
0000000
0
Initial value; Sens = SensPRE
Sensitivity (1)
QVO, Clamp Disable
(2)
Reserved (3)
Fuse Margin Lock
(4)
Blow
Lock
0111111
63
Maximum Sensitivity
1111111
127
Minimum Sensitivity value in range
0000000
0
Initial value
0001111
15
Maximum QVO
0010000
16
Minimum QVO
0100000
32
Disable Output Clamp
0000000
0
For factory use only. Programming:Sens coarse, Sensitivity TC and
QVO TC
000000001
1
Margin 10k
000000010
2
Margin comparator
000000100
4
Margin 150k
100000000
256
Lock Device
Absolute
Sensitivity Value
Absolute
QVO Value
Maximum
Maximum
Initial
0
Initial
63 64
127
Minimum
Figure 14: Sensitivity (1) Register
16Programming
Code
0
15 16
31
Code
Minimum
Figure 15: QVO (2) Register
is accomplished through the VOUT pin.
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Customer Programmable Linear Hall-Effect Sensor
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A1369
PACKAGE OUTLINE DRAWING
For Reference Only – Not for Tooling Use
(Reference DWG-9065)
Dimensions in millimeters – NOT TO SCALE
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
2 X 45°
B
4.09
+0.08
–0.05
1.52 ±0.05
E
2.04
C
3 X 10°
1.44 E
3.02
E
Mold Ejector
Pin Indent
+0.08
–0.05
45°
Branded
Face
1.02 MAX
1.02 MAX
A
0.79 REF
1
2
3
0.43
+0.05
–0.07
0.41
+0.03
–0.06
1.27 NOM
NNN
14.99 ±0.25
1
D
Standard Branding Reference View
= Supplier emblem
N = Last three digits of device part number
A
Dambar removal protrusion (6X)
B
Gate and tie bar burr area
C
Active Area Depth, 0.50 mm REF
D
Branding scale and appearance at supplier discretion
E
Hall element, not to scale
Figure 16: Package UA, 3-Pin SIP
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Customer Programmable Linear Hall-Effect Sensor
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A1369
Revision History
Revision
Revision Date
–
November 18, 2014
1
April 8, 2015
Description of Revision
Initial Release
Updated Programming Logic table; added Figures 14 & 15
Copyright ©2014-15, 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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