A1330-DS, Rev. 2
MCO-0000317
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
The A1330 is a 360° angle sensor IC that provides contactless
high-resolution angular position information based on magnetic
Circular Vertical Hall (CVH) technology. It has a system-on-
chip (SoC) architecture that includes: a CVH front end, digital
signal processing, and an analog output driver. It also includes
on-chip EEPROM technology, capable of supporting up to
100 read/write cycles, for flexible end-of-line programming
of calibration parameters. Broken ground wire detection and
user-selectable output voltage clamps make the A1330 ideal
for high-reliability applications requiring high-speed 0° to
360° angle measurements.
The A1330 provides adjustable internal averaging, allowing
response time to be traded for resolution. This is ideal for
applications operating at low rotational velocities requiring high
precision. For higher RPM applications, the A1330 provides
industry-leading analog response time when no averaging is
enabled.
With programmable angle scaling, the A1330 supports
applications requiring short angular displacements, while
maintaining full dynamic range on the output. Programmable
minimum and maximum angle thresholds allow diagnosis of
mechanical failures.
The A1330 is available as either a single or dual die option,
in an 8-pin TSSOP. The package is lead (Pb) free with 100%
matte-tin leadframe plating.
PACKAGE: 8-pin TSSOP (LE package)
Not to scale
Functional Block Diagram
• Contactless 0° to 360° angle sensor IC, for angular
position, rotational speed, and direction measurement
• Single and dual die options available in same package
• Non-volatile memory (EEPROM) for use in application
trimming/calibration
• Circular Vertical Hall (CVH) technology provides a
single-channel sensor system with air gap independence
• Angle Refresh Rate (output rate) configurable between
25 and 3200 µs through EEPROM programming
• Customer-programmable output clamp levels provide
short-circuit diagnostic capabilities
• Open-circuit detection on ground pin (broken wire)
• Undervoltage lockout for VCC below specification
• Fine angle scaling for short-stroke applications
• Missing Magnet Error flag for notifying controller of low
magnetic field level
• EEPROM programmable angle reference (0°) position
and rotation direction (CW or CCW)
• AEC-Q100 automotive qualified
FEATURES AND BENEFITS DESCRIPTION
SoC die 1
SoC die 2 (optional)
To all internal circuits
Multisegment
CVH Element ANALOG FRONTEND
Bandpass
Filter
Diagnostics
ADC
VCC
VOUT
GND
DIGITAL CONTROLLER
Temperature
Compensation
Internal Calibration
Zero Angle
Short Stroke
Interpolator
EEPROM
ANALOG BACKEND
Output
Buffer LPF
DIGITAL BACKEND
SD Mod
PWM MOD
Output
Controller
Regulator
August 3, 2018
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
2
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
ABSOLUTE MAXIMUM RATINGS
Characteristic Symbol Notes Rating Unit
Forward Supply Voltage VCC Not sampling angles 26.5 V
Reverse Supply Voltage VRCC Not sampling angles –18 V
Forward Output Voltage VOUT VOUT < VCC + 2 V 16 V
Reverse Output Voltage VROUT 0.5 V
Operating Ambient Temperature TAL range –40 to 150 °C
Maximum Junction Temperature TJ(max) 165 °C
Storage Temperature Tstg –65 to 170 °C
SELECTION GUIDE
Part Number Application Number of Die Package Packing [1]
A1330LLETR-T Analog Output Single Die
8-pin TSSOP 4000 pieces per 13-inch reel
A1330LLETR-P-T PWM Output Single Die
A1330LLETR-DD-T Analog Output Dual Die
A1330LLETR-P-DD-T PWM Output Dual Die
A1330LLETR-T-C02 Analog Output [2] Single Die
[1] Contact Allegro™ for additional packing options.
[2] Increased Angle averaging and Analog hysteresis settings for reduced angle noise.
THERMAL CHARACTERISTICS: May require derating at maximum conditions; see application information
Characteristic Symbol Test Conditions* Value Unit
Package Thermal Resistance RθJA
LE-8 single die package 145 °C/W
LE-8 dual die package 277 °C/W
*Additional thermal information available on the Allegro website.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
3
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Table of Contents
Features and Benefits ........................................................... 1
Description .......................................................................... 1
Packages ............................................................................ 1
Functional Block Diagram ..................................................... 1
Selection Guide ................................................................... 2
Absolute Maximum Ratings ................................................... 2
Thermal Characteristics ........................................................ 2
Pinout Diagrams and Terminal Lists ........................................ 4
Operating Characteristics ...................................................... 5
Typical Performance Characteristics ....................................... 7
Functional Description .......................................................... 8
Operational Modes ............................................................ 8
Angle Measurement .......................................................... 8
Short Stroke ..................................................................... 8
Output Types .................................................................... 8
Undervoltage and Overvoltage Lockout ............................. 10
Hysteresis ...................................................................... 10
Programming Serial Interface ...............................................11
Transaction Types ............................................................11
Writing the Access Code ...................................................11
Writing to Non-Volatile Memory ..........................................11
Writing to Volatile Registers .............................................. 12
Reading from EEPROM ................................................... 12
Error Checking ............................................................... 12
Serial Interface Reference ................................................... 13
Serial Interface Message Structure ................................... 14
Special Access Code Commands ..................................... 15
EEPROM Locking ........................................................... 16
Safety Features .............................................................. 16
Internal Detection Circuitry ............................................... 16
Detecting Broken Ground Wire ......................................... 16
Angle Compensation ....................................................... 18
Angle Averaging ............................................................. 18
Pre-Gain Offset ............................................................... 19
Polarity Adjust ................................................................ 19
Short Stroke ................................................................... 19
Clamp and Roll-Over Logic .............................................. 21
Additional Short Stroke Examples ..................................... 22
Application Information ....................................................... 24
Magnetic Target Requirements ......................................... 24
Field Strength ................................................................. 24
Setting the Zero-Degree Position ...................................... 25
Magnetic Misalignment .................................................... 25
Application Circuit Description .......................................... 26
ESD Performance ........................................................... 26
EEPROM Memory Map....................................................... 27
Package Outline Drawings .................................................. 35
APPENDIX A: Angle Error and Drift Definition .......................A-1
APPENDIX B: CRC Documentation ..................................... B-1
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
4
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Terminal List Table (Single Die)
Pin Name Pin Number Function
VCC 1 Device power supply. Serves as Manchester communication input
pin.
VOUT 2
Angle output (analog or PWM). Manchester output during serial
communication.
Input for EEPROM programming pulses.
NC* 3,5,6,7,8 Not connected; connect to ground for optimal ESD performance
GND 4 Ground
* NC pins must be tied to GND for optimum ESD performance.
PINOUT DIAGRAMS AND TERMINAL LIST TABLES
LE-8 Package Pinout
(single die)
VCC
VOUT
NC
GND
NC
NC
NC
NC
1
2
3
4
8
7
6
5
LE-8 Package Pinout
(dual die)
Terminal List Table (Dual Die)
Pin Name Pin Number Function
VCC_1 1 Device power supply. Serves as Manchester communication input
pin. (die 1)
VOUT_1 2
Angle output (analog or PWM). Manchester output during serial
communication.
Input for EEPROM programming pulses. (die 1)
NC* 3, 8 Not connected; connect to ground for optimal ESD performance
GND_1 4 Ground (die 1)
VCC_2 5 Device power supply. Serves as Manchester communication input
pin. (die 2)
VOUT_2 6
Angle output (analog or PWM). Manchester output during serial
communication.
Input for EEPROM programming pulses. (die 2)
GND_2 7 Ground (die 2)
* NC pins must be tied to GND for optimum ESD performance.
VCC_1
VOUT_1
NC
GND_1
NC
GND_2
VOUT_2
VCC_2
1
2
3
4
8
7
6
5
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
5
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Continued on the next page…
OPERATING CHARACTERISTICS: Valid over the full operating voltage and ambient temperature ranges, unless otherwise noted
Characteristics Symbol Test Conditions Min. Typ. Max. Unit
[1]
ELECTRICAL CHARACTERISTICS
Supply Voltage [2] VCC 4.5 – 5.5 V
Supply Current ICC
One die, analog output,
unloaded output
TA ≥ 25°C – 12 15 mA
TA < 25°C – 12.6 16 mA
One die, PWM output, unloaded output – 8.5 10 mA
Undervoltage Lockout Threshold
Voltage
[3]
VUVLO(H)
Maximum VCC , dV/dt = 1 V/ms, TA = 25°C,
A1330 sampling enabled, rising VCC
– – 4.65 V
VUVLO(L)
Maximum VCC , dV/dt = 1 V/ms, TA = 25°C,
A1330 sampling disabled, falling VCC
3.9 – 4.5 V
Undervoltage Lockout Threshold
Hysteresis VUVLO(HYS) dV/dt = 1 V/ms, TA = 25°C – 180 – mV
Overvoltage Lockout Threshold
Voltage
VOVLO(H)
Maximum VCC , dV/dt = –1 V/ms, TA = 25°C,
A1330 sampling disabled – 6.3 – V
VOVLO(L)
Maximum VCC , dV/dt = 1 V/ms, TA = 25°C,
A1330 sampling enabled 5.5 5.9 – V
Overvoltage Lockout Threshold
Hysteresis VOVLO(HYS) dV/dt = –1 V/ms, TA = 25°C – 450 – mV
Supply Zener Clamp Voltage VZSUP ICC = ICC + 3 mA, TA = 25°C 26.5 – – V
Reverse-Battery Current IRCC VRCC = 18 V, TA = 25°C – – 5 mA
Power-On Time
[4] tPO – 300 – µs
ANALOG OUTPUT CHARACTERISTIC
DC Output Resistance
[4] ROUT –1–Ω
Output Load Resistance
[4] RL
VOUT to VCC 4.7 – – kΩ
VOUT to GND 4.7 – – kΩ
Output Current Limit ILIMIT
Minimum output, shorted to 5 V 24 29 34 mA
Maximum output, shorted to GND – 3 – mA
Output Load Capacitance
[4] COUT – – 10 nF
Broken Wire Voltage VBRK(H) TA = 25°C, RL(PU) = 10 kΩ to VCC – VCC – V
VBRK(L) TA = 25°C, RL(PD) = 10 kΩ to GND – 130 – mV
Output Slew Rate SR 10 kΩ pull-up – 100 – V/ms
DAC Output Noise
[4] ANOISE
DAC output, excluding angle measurement
noise, 30 kHz BW setting ––15 mVp-p
DAC output, excluding angle measurement
noise, 15 kHz BW setting ––10 mVp-p
Average DAC Resolution
[4] Res(avg) Across entire code range, theoretical noise-
free input, 30 kHz BW –12 – bits
Output Ratiometry Error [4] RatERROR –<±1 – %
Analog Drift |VDRIFT|
Absolute change in analog output from 25°C
to 150°C –10 30 mV
Absolute change in analog output from 25°C
to –40°C –10 – mV
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
6
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
OPERATING CHARACTERISTICS (continued): Valid over the full operating voltage and ambient temperature ranges,
unless otherwise noted
Characteristics Symbol Test Conditions Min. Typ. Max. Unit
[1]
ANALOG OUTPUT CHARACTERISTIC (continued)
Output Saturation Voltage
VOUT(MAX)
Max input angle position; VCC = 5 V,
HIGH_CLAMP = 0 4.65 4.75 – V
VOUT(MIN)
0° input angle position; VCC = 5 V,
HIGH_CLAMP = 0 –0.25 0.35 V
OUTPUT CLAMP PROGRAMMING
Clamp High
[4] VCLAMP(H)
Valid for Analog or PWM output,
EEPROM programmable 32 – 95 % VCC or DC
Clamp Low
[4] VCLAMP(L)
Valid for Analog or PWM output,
EEPROM programmable 5 – 68 % VCC or DC
PWM INTERFACE SPECIFICATIONS
PWM Carrier Frequency
[4] fPWM Programmable, 3 bit field 156.25 1250 20,000 Hz
Output Current Limit ILIMIT Minimum output, shorted to 5 V 24 29 34 mA
Pull-up Load [5] RL4.7 – – kΩ
PWM Duty Cycle Minimum [4] DPWM(MIN) LOW_CLAMP = 0 – 5 – %
PWM Duty Cycle Maximum [4] DPWM(MAX) HIGH_CLAMP = 0 – 95 – %
MAGNETIC CHARACTERISTICS
Magnetic Field B Range of input field – – 1200 G
ANGLE CHARACTERISTICS
Output
[5] RESANGLE – 12 – bit
Angle Refresh Rate
[6] tANG ANG_AVE = 0 – 25 – µs
Response Time
[4] tRESPONSE
ANG_AVE = 0 – 120 – µs
ANG_AVE = 3 – 200 – µs
Temperature Drift ANGLEDRIFT
Angle change from 25°C; TA = 150°C, B = 300 G –1.8 0.5 1.8 degrees
Angle change from 25°C; TA = –40°C, B = 300 G – 0.8 – degrees
Angle Error ERRANG
TA = 25°C, ideal magnet alignment, B = 300 G –1.1 ±0.4 1.1 degrees
TA = 150°C, ideal magnet alignment, B = 300 G –1.5 ±0.5 1.5 degrees
Angle Noise NANG
TA = 25°C, B = 300 G, no internal filtering,
target rpm = 0, 3 sigma, PWM output – ±0.6 – degrees
TA = 150°C, B = 300 G, no internal filtering,
target rpm = 0, 3 sigma, PWM output – ±0.75 – degrees
Angle Drift Over Lifetime [7] ANGLEDRIFT_LIFE
B = 300 G, typical angle drift observed
following AEC-Q100 qualification testing – ±0.5 – degrees
[1] 1 G (gauss) = 0.1 mT (millitesla).
[2] Operation guaranteed down to 4.5 V, once VCC has risen above 4.65 V.
[3] At power-on, the sensor IC will not respond to commands until VCC rises above VUVLO(H). After that,
the sensor IC will perform and respond normally until VCC drops below VUVLO(L)
.
[4] Parameter is not guaranteed at nal test. Values for this characteristic are determined by design.
[5] RESANGLE represents the number of bits of internal angle information available.
[6] The rate at which a new angle reading will be ready.
[7] Maximum of 1.0 degree increase in angle error observed following AEC-Q100 stress.
Angular Position
Transducer Output
50
0
(%)
Response Time, tRESPONSE
t
Denition of Response Time
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
7
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
TYPICAL PERFORMANCE CHARACTERISTICS
Figure 1: Peak Angle Error over Temperature
(300 G)
Figure 2: Maximum Absolute Drift from 25°C Reading
(300 G)
Figure 3: Noise Performance over Temperature
(3 Sigma, 300 G, no internal filtering,
Analog Output, 1 nF output capacitance)
Figure 4: ICC over Temperature
(VCC = 5.0 V)
-40 -20 020406080 100 120 140
Ambient Temperature in Degrees C
7
8
9
10
11
12
13
14
15
I
CC
in mA
Analog Output
PWM Output
+/-3 Sigma
-40 -20 020406080 100 120 140
Ambient Temperature in Degrees C
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Noise in degrees
Mean
+/- 3 Sigma
0 50 100 150
Ambient Temperature in Degrees C
0
0.5
1
1.5
2
Angle Error in Degrees
Mean
+/- 3 Sigma
0 50 100 150
Ambient Temperature in Degrees C
0
0.5
1
1.5
2
Angle Drift in Degrees
Mean
+/- 3 Sigma
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
8
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
FUNCTIONAL DESCRIPTION
Operational Modes
The A1330 is a rotary position Hall-effect-based sensor IC. The
sensor IC measures the direction of the magnetic field vector
through 360° in the x-y plane (parallel to the branded face of the
device) and computes an angle measurement based on the actual
physical reading, as well as any internal parameters that have
been set by the user.
The device is a programmable system-on-chip (SoC). The
integrated circuit includes a Circular Vertical Hall (CVH) analog
front end, a high-speed sampling A-to-D converter, digital filter-
ing, digital signal processing, and a high-speed Digital-to-Analog
converter.
Internal averaging may be enabled to improve signal resolution.
Advanced offset and gain adjustment options are available in the
A1330. These options can be configured in the onboard EEPROM,
providing a wide range of sensing solutions in the same device.
Device performance can be optimized by enabling individual func-
tions or disabling them in EEPROM to minimize latency.
Angle Measurement
The A1330 can monitor the angular position of a rotating magnet
at speeds ranging from 0 to more than 7,000 rpm.
The raw angle data is received in a periodic stream, and several
samples may be accumulated and averaged, based on a user-
selected EEPROM field. This feature increases the effective resolu-
tion of the system. The amount of averaging is determined by the
user-programmable ANG_AVE field. The user can configure the
quantity of averaged samples by powers of two to determine the
refresh rate, the rate at which successive averaged angle values are
fed into the post-processing stages. The available rates are set as
follows:
ANG_AVE [2:0] Quantity of Samples Averaged Refresh Rate (µs)
000 1 25
001 2 50
010 4 100
011 8 200
100 16 400
101 32 800
110 64 1600
111 128 3200
Short Stroke
Short stroke (or fine angle scaling) allows for magnetic angle
rotations smaller than 360 degrees to be represented by full-scale
deflection. This feature is enabled in “Short Stroke” mode. In
this mode, the raw angle reading is scaled via a programmable
GAIN setting. Minimum and maximum angle thresholds may
be programmed to detect hardware malfunctions. When a raw
angle greater than the maximum angle threshold is detected, the
sensor output will tri-state, alerting the host microprocessor of an
unexpected condition. Programmable Clamp_High and Clamp_
Low settings allow the maximum or minimum output level to be
customizable.
Output Types
The A1330 is set at Allegro factory for either analog or PWM output.
ANALOG OUTPUT
The A1330LLETR-T and A1330LLETR-D-T feature an ana-
log output, proportional to a 12-bit digital angle value. Angles
0.0 through 359.9 degrees are mapped to voltages between the
default VCLAMPL and default VCLAMPH. The output voltage will
increase linearly, between the clamp settings when a linearly
increasing magnetic angle is detected.
Voltage values beyond the upper or lower clamps represent
diagnostic regions. Output voltages within these two regions will
only occur if the device detects an abnormal operating condition
or internal error.
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
00 72 144 216 288 360 432 504 576 648 720
VOUT
Angles (degrees)
Lower Diagnostic Region
Clamp Low
Linear Range
Clamp High
Upper Diagnostic Region
Figure 5: Output Value for a 0-720° Magnetic Input Signal
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
9
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
BACKEND DAC BW
The bandwidth of the backend analog filter is adjustable in
EEPROM between two settings.
ABW DAC Bandwidth
0 30 kHz
1 15 kHz
The default setting of 30 kHz is recommended for most appli-
cations, providing a good balance between low noise and fast
response time. For applications especially sensitive to noise, it
is recommend to choose the 15 kHz option and use the internal
digital averaging to further reduce front end noise.
PWM OUTPUT
The A1330LLETR-P-T and A1330LLETR-P-DD-T provide a
pulse-width-modulated open-drain output, with the duty cycle
(D) proportional to measured angle. The PWM duty cycle is
clamped at 5% and 95% by default and may be adjusted further
for diagnostic purposes.
A 5% D corresponds to 0°; a 95% D corresponds to 360°.
0T
D = 5%
0
360
D = 50% D = 95%
Magnetic Field Angle (°)
PWM Waveform (V)
1T
D
1T
D
2T
D
4T
D
3T
D
0T
D
5T
t
pulse(5)
T
period
D
6T
D
7T
D
8T
D
(x)
= t
pulse(x)
/
T
period
D
9T
D
10T
HIGH_CLAMP
LOW_CLAMP
2T 3T 4T 5T 6T 7T 8T 9T 10T 11T Time
Figure 6: PWM Mode Outputs a Duty Cycle
Proportional to Sensed Angle
Angle is represented in 12-bit resolution and can never reach a
full 360° (0° and 360° are the same physical position). The maxi-
mum duty cycle high period with default clamp values is:
DutyCycleMax (%) = (4095 / 4096) × 90 + 5.
The derived angle (in degrees) from a given PWM duty cycle is:
Angle = (D – 5) / 90 × 360.
5 % LOW
5 % HIGH
5 % LOW
5 % HIGH
5 % LOW
5 % HIGH
5 % LOW
5 % HIGH
5 % LOW
5 % HIGH
5 % LOW
5 % HIGH
PWM Period
PWM Period
(0 Degrees)
120
Degrees
240 Degrees360 Degrees
PWM Period
PWM Period
Figure 7: Pulse-Width Modulation (PWM) Examples
PWM CARRIER FREQUENCY
The PWM carrier frequency is controlled via a 3-bit EEPROM
field.
PWM_FREQ PWM Frequency
000 20 kHz
001 10 kHz
010 5 kHz
011 2.5 kHz
100 1.25 kHz
101 625 Hz
110 312.5 Hz
111 156.25 Hz
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
10
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
V
CC
(V)
7.0
4.0
3.8
1.5
t
6.0
5.5
4.5
4.65
Undervoltage Lockout
Threshold Voltage (High), VUVLO(H)
DIGON
Tri-State Tri-State
Accuracy
Reduced
Valid
Output
Tri-State
Undervoltage Lockout
Threshold Voltage (Low), VUVLO(L)
Overvoltage Lockout
Threshold Voltage (High), VOVLO(H)
Overvoltage Lockout
Threshold Voltage (Low), VOVLO(L)
Accuracy
Reduced
Valid
Output
Accuracy
Reduced
Output Pin State
Accuracy
Reduced
Figure 8: Relationship of VCC and Output
Undervoltage and Overvoltage Lockout
The Output pin state changes according to the VCC level. This is
shown in Figure 8, with typical threshold values highlighted. By
using a pull-up/pull-down resistor, one is able to know the sensor
is in high-impedance, as the output will be beyond the clamp
values.
Hysteresis
The periodic behavior intrinsic to angle sensing results in output
voltage swings from minimum to maximum deflection during
0/360 degree crossings. For some applications, this may be prob-
lematic, especially if a high-noise environment results in values
close to 0 degrees intermittently appearing as 359.9 degrees.
To prevent oscillations between mininimum or maximum output,
the A1330 features programmable hysteresis, specified by the
2-bit HYST EEPROM field. When hysteresis is enabled, the
output will not change for angle variations smaller than the hys-
teresis setting.
As an alternate approach, the HYST_0/360 bit may be set in
EEPROM, to enable hysteresis only around the 0/360 degree
crossing.
Note: Unlike the typical description of ‘Hysteresis”, the imple-
mentation used in the A1330 is “two-sided”, meaning the hys-
teresis gap is independent of rotation direction. This effectively
increases the output step size and as a result may not be desired.
To apply this filtering method to only angle ranges of importance
(in which a 0/360 crossover could occur), the HYST_0/360 bit
can be set.
Table 1: HYST Settings in EEPROM
Code Hysteresis (in LSB) Angle Equivalent
00 0 0
01 4 0.352
10 8 0.703
11 16 1.406
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
11
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
PROGRAMMING SERIAL INTERFACE
The A1330 incorporates a serial interface that allows an external
controller to read and write registers in the A1330 EEPROM and
volatile memory. The A1330 uses a point-to-point communication
protocol, based on Manchester encoding (a rising edge indicates a
0 and a falling edge indicates a 1), with address and data trans-
mitted MSB first.
Transaction Types
Each transaction is initiated by a command from the controller; the
A1330 does not initiate any transactions. Two commands are rec-
ognized by the A1330: Write and Read. There also are three special
function Write commands: Write Access Code, Manchester Enable,
and Manchester Disable. One response frame type is generated by
the A1330, Read Acknowledge.
If the command is a read, the A1330 responds by transmitting the
requested data in a Read Acknowledge frame. If the command is
a write, the A1330 does not acknowledge.
As shown in Figure 9, The A1330 receives all commands via the
VCC pin. It responds to Read commands via the VOUT pin. This
implementation of Manchester encoding requires the commu-
nication pulses be within a high (VMAN(H)) and low (VMAN(L))
range of voltages for the VCC line and the VOUT line. The Write
command pulses to EEPROM are supported by two high-voltage
pulses on the VOUT line.
A1330
Controller
GND
Read Acknowledge
Manchester Code
Write/Read Command
Manchester Code
VCC
VOUT
High Voltage pulses to
activate EEPROM cells
to logic high supply
Figure 9: Top-Level Programming Interface
Writing the Access Code
If the external controller will write to or read from the A1330 mem-
ory during the current session, it must establish serial communica-
tion with the A1330 by sending a Write Access Command within
70 ms after powering up the A1330. If this deadline is missed, all
write and read access is disabled until the next power-up.
Writing to EEPROM
When writing to non-volatile EEPROM, following the write com-
mand, the controller must also send two Programming pulses.
These pulses are well-separated, long, high-voltage strobes
transmitted on the VOUT pin. These strobes are detected internally,
allowing the A1330 to boost the voltage on the EEPROM gates.
The digital logic will automatically detect an impending EEPROM
write and tri-state the output pin.
The required sequence is shown in Figure 12. The voltage pulse
profile necessary for EEPROM programming is shown in Figure
10. Minimum and maximum times are described in Table 2.
>300 µs
10 ms
>60 µs
2 µs
>300 µs
10 ms
>60 µs
ERASE PROGRAM
18 V
6 V
Figure 10: Top-Level Programming Interface
Table 2: EEPROM Pulse
Parameter Comments Min. Typ. Max. Unit
Pulse High Time Time above minimum pulse
voltage
8 10 11 ms
Rise Time 10% to 90% of minimum
pulse level
300 – – µs
Fall Time 10% to 90% of minimum
pulse level
60 – – µs
Pulse Voltage 18 19 19.5 V
Separation time Time between first pulse
dropping below 6 V and 2nd
pulse rising above 6 V
2 µs – 50 ms µs/ms
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
12
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Writing to Volatile Registers
The three main volatile write commands (Write Access, Man-
chester Enable and Manchester Disable) are all accomplished by
writing to register 0x1F.
In addition to these three commands, the PWM output version
requires a PWM Disable command be written prior to perform-
ing a Manchester read and a PWM Enable command prior to
going back to Normal Mode. These two commands are written to
register 0x22.
Reading from EEPROM
To read from EEPROM, the Manchester mode must be entered.
This is accomplished by sending the Manchester Enable code on
VCC. For PWM parts, an additional PWM Disable command
must also be sent.
After the Read Acknowledge frame has been received from the
A1330, the controller must send a Manchester Disable command
to restore VOUT to normal operation. The required sequence is
shown in Figure 12.
Error Checking
The serial interface uses a cyclic redundancy check (CRC) for
data-bit error checking (synchronization bits are ignored during
the check).
The CRC algorithm is based on the polynomial
g(x) = x3 + x + 1 ,
and the calculation is represented graphically in Figure 11.
The trailing 3 bits of a message frame comprise the CRC token.
The CRC is initialized at 111.
C1C0 C2 Input Data
1x 01x 10x 21x 3= x3 + x + 1
Figure 11: CRC Calculation
Write Access
Command
EEPROM
Write
Write Access
Command
Manchester
Enable Command
EEPROM
Read
Manchester
Disable
Read
Acknowledge
Normal Operation
Normal Operation
Normal Operation
Normal Operation
Write To
EEPROM
Read From
EEPROM
VCC
VOUT
VCC
VOUT
GND
GND
<70 ms from power-on
<70 ms from power-on
High
Impedance
High
Impedance
EEPROM
Programming
Pulses
t
t
td(WRITE,E)
td(DIS_OUT) t
d(START_READ)
t
d(START_READ)
t
d(ENB_OUT)
ts(PULSE,E)
Figure 12: Programming Read and Write Timing Diagrams
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
13
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
SERIAL INTERFACE REFERENCE
Table 3: Serial Interface Protocol Characteristics
[1]
Characteristics Symbol Note Min. Typ. Max. Unit
INPUT/OUTPUT SIGNAL TIMING
Access Code Timeout tACC
Customer Access Code should be fully entered
in less than tACC, measured from when VCC
crosses VCC(UVH)
– – 70 ms
Baud Rate fs
Defined by the input message bit rate sent from
the external controller 5 – 40 kbps
Bit Time Error errTBIT Deviation in tBIT during one command frame –15 – +15 %
Read Acknowledge Delay td(READ)
Required delay from the trailing edge of a Read
Acknowledge frame to the leading edge of a
following command frame
2 × tBIT – – µs
Read Delay
[2] td(START
_
READ)
Delay from the trailing edge of a Read
command frame to the leading edge of the Read
Acknowledge frame
– 2 × tBIT – µs
Enable Manchester Delay
[2] td(DIS_OUT)
Delay from the trailing edge of a Manchester
Enable command frame to the device output
going from normal operation to the high-
impedance state
1 –
¼ × tBIT
5 –
¼ × tBIT
15 –
¼ × tBIT
µs
Disable Manchester Delay
[2] td(ENB_OUT)
Delay from the trailing edge of a Manchester
Disable command frame to the device output
going from the high-impedance state to normal
operation
1 –
¼ × tBIT
5 –
¼ × tBIT
15 –
¼ × tBIT
µs
EEPROM PROGRAMMING PULSE
EEPROM Programming Pulse
Setup Time ts(PULSE,E)
Delay from last bit cell of write command to start
of EEPROM programming pulse 2 × tBIT – – μs
EEPROM Memory Write Delay td(WRITE,E)
Required delay from the trailing edge of the
second EEPROM Programming pulse to the
leading edge of a following command frame
40 – – µs
INPUT SIGNAL VOLTAGE
Manchester Code High Voltage VMAN(H) Applied to VCC line 7.3 – – V
Manchester Code Low Voltage VMAN(L) Applied to VCC line – – 6.3 V
OUTPUT SIGNAL VOLTAGE (APPLIED ON PWM LINE)
Manchester Code High Voltage VMAN(H)
Minimum Rpullup = 5 kΩ 0.9 × VS– – V
Maximum Rpullup = 50 kΩ 0.7 × VS– – V
Manchester Code Low Voltage VMAN(L) 5 kΩ ≤ Rpullup ≤ 50 kΩ – – 0.35 V
[1] Determined by design.
[2] In the case where a slower baud rate is used, the output responds before the transfer of the last bit in the command message is completed.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
14
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Serial Interface Message Structure
The general format of a command message frame is shown in
Figure 13. Note that, in the Manchester coding used, a bit value
of 1 is indicated by a falling edge within the bit boundary, and
a bit value of zero is indicated by a rising edge within the bit
boundary.
Each command is composed of two zero synchonization bits
(“00”) followed by a Read/Write bit, 6 bit address, 32 data bits
(only for write commands) and 3 bits of CRC. All field are inter-
preted MSB first.
The read acknowledged frame is composed of two zero synchro-
nization bits, 32 bits of data, and a 3 bit CRC.
The bits are described in Table 4.
Synchronize
Read
/
Write
MSB MSB
Manchester Code per G. E. Thomas
Bit boundaries
Memory Address Data CRC
0/10 0 0/1 0/1 0/1 0/1 0/1
0 00 1 1
0/1 0/1 0/1 C20/1 . . . 0/1 0/1 C0C1
Figure 13: General Format for Serial Interface Commands
Table 4: Serial Interface Command General Format
Quantity of Bits Name Values Description
2 Synchronization 00 Used to identify the beginning of a serial interface command and communication bit time
1 Read/Write 0 [As required] Write operation
1 [As required] Read operation
6 Address 0/1 [Read/Write] Register address (volatile memory or EEPROM)
variable Data 0/1 [As required] 32 bits of data
3 CRC 0/1 Incorrect value indicates errors
Write Command
tBIT
Address Data CRC0 0 0
(Write)
t
A5 A4 A0 D31 D30 D0 C2 C1 C0
Read Command
tBIT
Address CRC0 0 1
(Read)
t
A5 A4 A0 C2 C1 C0
Read Acknowledge
tBIT
Data CRC0 0
t
D31 D30 D0 C2 C1 C0
Figure 14: Manchester Format Example
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
15
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Special Access Code Commands
There are two Manchester code commands: a write access code,
which initiates serial communication and must be sent within
tACC of power up; and a Disable Output Command, which toggles
between mission mode (normal sensor behavior) and Manchester
mode, allowing the part to respond to read requests. Both com-
mands are written to volatile register 0x1F.
1. Write Access Code:
Unlocks the customer address space.
2. Manchester Enable Command:
Disables sensor output, allowing sensor to respond with a
read acknowledge frame.
3. Manchester Disable Command:
Exits Manchester mode and returns the sensor normal output
mode.
The PWM varient requires two additional commands.
1. PWM Disable Code:
Disables the PWM modulator, allowing Manchester logic to
control the open drain output. Must be sent after the Man-
chester Enable pulse, and prior to a read request.
2. PWM Enable Code:
Moves control of the output driver back to the PWM logic.
Must be sent prior to Manchester Disable command.
Write Access Code
String ASCII Code (hex)
“1330” 31 33 33 30
Manchester Enable Code
String ASCII Code (hex)
“READ” 52 45 41 44
Manchester Disable Code
String ASCII Code (hex)
“EXIT” 45 58 49 54
PWM Disable Code
Address Hex Code
0x22 0x01E6C0D
PWM Enable Code
Address Hex Code
0x22 0x21E6C0D
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
16
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
EEPROM Locking
The EEPROM contains an EELOCK bit. When set high, this bit
prevents the writing of all EEPROM locations. This is a safety
feature guaranteeing EEPROM content integrity during operation
in the field.
Safety Features
Lockout and clamping features protect the A1330 internal circuitry
and prevent spurious outputs when the supply voltage is out of
specification. Open ground circuit detection is also provided.
Internal Detection Circuitry
Internal diagnostic circuitry monitors EEPROM ECC to ensure
valid system configurations. Magnetic field amplitude is com-
pared against a low field threshold to identify possible hardware
malfunctions.
During short stroke mode, minimum and maximum angle values
may be specified to identify unexpected behavior and place the
output in a safe state.
These diagnostic modes may be disabled with an EEPROM mask
bit.
Detecting Broken Ground Wire
If the GND pin is disconnected, node A becoming broken (Figure
15), the VOUT pin will go to a high-impedance state. Output
voltage will go to VBRK(H) if a load resistor RL(PU) is connected to
VCC or to VBRK(L) if a load resistor RL(PD) is connected to GND.
The device will not respond to a magnetic field.
If the ground wire is reconnected, the A1330 will resume normal
operation.
A
Connecting VOUTto R
L(PU)
A1330
VCC
V
CC
V
CC
RL(PU)
GND
VOUT
GND
A
VOUT
A1330
VCC
V
CC
RL(PD
)
Connecting VOUT to R
L(PD)
Figure 15: Connection for Detecting Broken Ground Wire
Table 5: Safety Features
Diagnostic/Protection Description Output State
Reverse VCC Current limiting (VCCx pin) –
Output to VCC Current limiting (VOUT pin) –
Output to Ground Current limiting (VOUT pin) –
UVLO VCC below expected range Tri-state
OVLO VCC above expected range Tri-state
EEPROM dual bit fault Uncorrectable EEPROM bit fault. Proper device configuration cannot be
guaranteed Tri-state
Missing Magnet Monitors magnet field level in case of mechanical failure (default of 100 G) Tri-state
Angle Out of Range During short-stroke operation, measured raw angle exceeds maximum
specified angular displacement Tri-state
Broken Ground Wire Broken ground connection Tri-state: output goes to VBRK(H) or
VBRK(L)
Digital Interpolation Error Internal monitor of the DAC interpolation block detects unexpected internal
register changes and resets the interpolator Tri-state
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
17
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
CVH
Analog
Condioning
ADC
Angle
Compensaon
Pre-Gain Offset
Polarity Adjust
Short Stroke
Mapper
PWM OutDAC
Factory
Configured Digital
Analog Front End
Programmable
Digital
Adjustment
Back End
Angle
Averaging
Figure 16: Digital Signal Path Description
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
18
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Angle Compensation
The A1330 is capable of compensating for alterations in angle
readings that result from changes in the device temperature or
applied field strength. The device comes from the factory pre-
programmed with coefficient settings to allow compensation of
linear shifts of angle with temperature and applied field.
Angle Averaging
The raw angle data is received in a periodic stream, and multiple
samples may be accumulated and averaged, based on the user-
programmable ANG_AVE EEPROM field. This feature increases
the effective resolution of the system. The user can configure the
quantity of averaged samples by powers of two to determine the
refresh rate, the rate at which successive averaged angle values
are fed into the post-processing stages. The available rates are set
as follows:
Table 6: Refresh Rate based on Averaged Samples
ANG_AVE [2:0] Quantity of Samples
Averaged
Refresh Rate (µs)
000 1 25
001 2 50
010 4 100
011 8 200
100 16 400
101 32 800
110 64 1600
111 128 3200
01234567
Averaging Setting
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Noise in Degrees
300 G
600 G
900 G
Figure 17: 3 Sigma Angle Noise Over
Averaging Settings. PWM Output, 25°C, Multiple Field Levels.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
19
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Pre-Gain Offset
Allows zeroing of the angle prior to applying gain. Set via the
PREGAIN_OFFSET field in EEPROM.
Angle = Angle – PREGAIN_OFFSET
Polarity Adjust
Sets the polarity of the final angle output. When set to “1”, the
angle is complemented.
Angle = 360° – Angle
Short Stroke
The A1330 features “short stroke” logic allowing a limited input
signal to be gained up and use the full output range of the sensor.
The short stroke logic consists of multiple steps. A high level
block diagram is shown in Figure 18. Short stroke applies to both
the PWM and analog output variants.
Pre-Gain Offset
Min/Max Input
Comparison
Short Stroke
Enabled?
Gain
Post Gain
Offset
Yes No
Clamp and Roll-
Over Logic
Angle In
Polarity Adjust
Figure 18: High Level Short Stroke Block Diagram
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
20
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
MIN/MAX INPUT ANGLE COMPARISON
The IC compares the pre-gained angle value to the boundaries
set via the MIN_INPUT and MAX_INPUT EEPROM fields. If
the angle is outside of the established boundaries the output will
tristate to indicate an unexpected angle location. This feature is
useful for applications where clamping is enabled and will other-
wise mask excessive angular travel.
GAIN
Adjusts the output dynamic range of the device. Gain is applied
digitally and capable of expanding an 11.25° input angle to a full
scale output deflection.
It should be noted that with application of high gain, the front end
noise will also be amplified. In such cases it is highly recommend
to use the Angle Averaging feature to minimize the impact of noise.
When applying a non-integer gain, an asymetric transfer function
will result, causing the output to jump to the minimum allowed
output value before reaching the maximum allowed output value.
As an example, if a gain of 4× is applied, with Clamp Enable
(CE) and Roll-Over Enable (ROE) set to 0, the output angle will
slew from 0-360° four times for a single 0-360° target rotation
(this is shown in Figure 19 for 2 rotations of the target). However,
if a gain of 4.5× is applied, the output will slew from 0-360° four
and a half times. This results in a jump from 180° output to 0°
output, at the 360° input position (shown in Figure 20).
POST-GAIN OFFSET
Provides a final, post-gain angle adjustment.
0 100 200 300 400 500 600 700
Target Rotation
0
50
100
150
200
250
300
350
Sensor Output (degrees)
Sensor Output (degrees)
0/360 Roll-over
Figure 19: A1330 Output (in degrees) with 4.0× Gain
0 100 200 300 400 500 600 700
Target Rotation
0
50
100
150
200
250
300
350
Sensor Output (degrees)
Sensor Output (degrees)
0/360 Roll-over
Figure 20: A1330 Output (in degrees) with 4.5× Gain
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
21
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Clamp and Roll-Over Logic
Output behavior following gain and offset application is defined
by the Clamp Enable (CE) and Roll-Over Enable (ROE)
EEPROM bits. Together these two field select between four dif-
ferent output behavior types.
Below are figures depicting the output behavior with different
clamp and roll-over settings.
Figure 21: CE = 0, ROE = 0. Applied gain = 4×.
Figure 22: CE = 1, ROE = 0. Applied gain = 4×.
LOW_CLAMP = 10 (≈40°), HIGH_CLAMP = 10 (≈320°)
Figure 23: CE = 0, ROE = 1. Applied gain = 4×.
LOW_CLAMP = 10 (≈40°), HIGH_CLAMP = 10 (≈320°)
CE ROE Description
0 0 Normal behavior.
Roll-over at standard module 360.
0 1 Output rolls-over at the High and Low Clamp
values.
1 0 Output clamps at the first encountered High/
Low Clamp value.
1 1 Roll-over occurs at standard module 360.
Output is clamped to High/Low Clamps value.
Figure 24: CE = 1, ROE = 1. Applied gain = 4×.
LOW_CLAMP = 10 (≈40°), HIGH_CLAMP = 10 (≈320°)
Clamping Only
Input Angle (degrees)
Output Angle (degrees)
0 360
0
360
40
320
High_Clamp
Low_Clamp
No Clamping or Rollover
Output Angle (degrees)
0 360
0
360
Rollover Only
Input Angle (degrees)
Output Angle (degrees)
0 360
0
360
40
320
High_Clamp
Low_Clamp
Clamping + Rollover
Input Angle (degrees)
Output Angle (degrees)
0 360
0
360
40
320
High_Clamp
Low_Clamp
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
22
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Additional Short Stroke Examples
To demonstrate short stroke, several possible scenarios are shown
in the following figures.
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
00 50 100 150 200 250 300 350
VOUT
Magnetic Angle
Low Clamp = 0.25
High Clamp = 4.75
Range = 0 to 360
Gain = 1.00, Min Angle = 0, MAX_INPUT = 360
Clamps
Output
Figure 25: Scenario A.
Regular output for a 0-360 degree input angle.
Gain = 1. Clamps set to 95% and 5%.
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
00 50 100 150 200 250 300 350
VOUT
Magnetic Angle
Low Clamp = 0.25
High Clamp = 4.75
Range = 0 to 360
Gain = 1.00, MIN_INPUT = 0, MAX_INPUT = 300
Clamps
Output
Figure 26: Scenario B.
Regular 0-360 degree input value. Gain = 1.
MAX_INPUT = 300. Clamps set to 95% and 5%.
Output goes into diagnostic region (in this case VCC) when
input angle exceeds the MAX_INPUT set point.
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
00 50 100 150 200 250 300 350
VOUT
Magnetic Angle
Low Clamp = 0.25
High Clamp = 4.75
Range = 0 to 60
Gain = 1.00, MIN_INPUT = 0, MAX_INPUT = 360
Clamps
Output
Figure 27: Scenario C.
0-60 degree input. Gain = 1.
With no gain, a 60-degree input angle results in an output
signal 1/6th of VCC.
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
00 50 100 150 200 250 300 350
VOUT
Magnetic Angle
Low Clamp = 0.25
High Clamp = 4.75
Range = 0 to 60
Gain = 3.00, MIN_INPUT = 0, MAX_INPUT = 360
Clamps
Output
Figure 28: Scenario D.
0-60 degree input. Gain = 3.
With an increased Gain value of 3×, the same 60-degree input
signal now results in 50% of VCC. The output signal is still free to
swing from 5% to 95% of VCC.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
23
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
00 50 100 150 200 250 300 350
VOUT
Magnetic Angle
Low Clamp = 0.25
High Clamp = 2.50
Range = 0 to 80
Gain = 3.00, MIN_INPUT = 0, MAX_INPUT = 360
Clamps
Output
Figure 29: Scenario E.
0-80 degree input. Gain = 3.
High Clamp reduduced to 50% of VCC.
60-degree input results in 50% output signal. With the reduced up-
per clamp value, maximum VOUT is 50% of VCC. Angle measure-
ments greater than 60 degrees will be clamped to this 50% value.
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
00 50 100 150 200 250 300 350
VOUT
Magnetic Angle
Low Clamp = 0.25
High Clamp = 2.50
Range = 0 to 100
Gain = 3.00, MIN_INPUT = 0, MAX_INPUT = 90
Clamps
Output
Figure 30: Scenario F.
0-100 degree input. Gain = 3. Clamp_High reduced to 50% VCC. MAX_INPUT =
90°. Similar to the above scenario, output voltage is clamped at 50% of VCC
for any input angle greater than 60 degrees. However, when the input angle
exceeds the MAX_INPUT threshold, output voltage goes to diagnostic state
(VCC). In this example, if the expected input range is 60 degrees, a mechani-
cal failure resulting in 100 degrees of rotation will be detected.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
24
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
APPLICATION INFORMATION
Magnetic Target Requirements
The A1330 is designed to operate with magnets constructed with
a variety of magnetic materials, cylindrical geometries, and field
strengths, as shown in Table 7. Contact Allegro for more detailed
information on magnet selection and theoretical error.
Field Strength
The A1330 actively measures and adapts to its magnetic envi-
ronment. This allows operation throughout a large range of
field strengths (recommended range is 300 to 1000 G, operation
beyond this range is allowed with no long-term impact). Due to
the greater signal-to-noise ratio provided at higher field strengths,
performance inherently increases with increasing field strength.
Typical angle performance over applied field strength and tem-
perature are shown in Figure 32 and Figure 33.
Table 7: Target Magnet Parameters
Magnetic Material Diameter
(mm)
Thickness
(mm)
Neodymium (bonded) 15 4
Neodymium (sintered)* 10 2.5
Neodymium (sintered) 8 3
Neodymium / SmCo 6 2.5
NS
Thickness
Diameter
*A sintered Neodymium magnet with 10 mm (or greater) diameter and 2.5 mm
thickness is the recommended magnet for redundant applications.
Figure 32: Typical Three Sigma Angle Noise
Over Field Strength
Figure 33: Typical Angle Error
Over Field Strength
100 200 300 400 500 600 700 800 900
Field Strength in Gauss
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Angle Noise in Degrees
-40°C
-10°C
25°C
85°C
125°C
150°C
Recommended Operating Range
(300 G and above)
100 200 300 400 500 600 700 800 900
Field Strength in Gauss
0
0.5
1
1.5
2
2.5
Angle Error in Degrees
-40°C
-10°C
25°C
85°C
125°C
150°C
Recommended Operating Range
(300 G and above)
Magnetic Field
(G)
1600
1400
1200
1000
600
400
SmCo24
NdFe30
200
0
Ceramic
(Ferrite)
0.5 2.5 4.5 6.5 8.5
800
Figure 31: Magnetic Field versus Air Gap for a magnet
6 mm in diameter and 2.5 mm thick. Allegro can provide
similar curves for customer application magnets upon re-
quest. Allegro recommends larger magnets for applications
that require optimized accuracy performance.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
25
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Setting the Zero-Degree Position
When shipped from the factory, the default angle value when
oriented as shown in Figure 34 is ≈162° for die 1 and ≈342° for
die 2. In some cases, the end user may want to program and angle
offset to compensate for variations in magnetic assemblies, or for
applications where absolute system level readings are required.
The A1330 features two different offset adjust field in EEPROM,
which may be used to change the location of the 0/360°discon-
tinuity point. Depending on application either the PREGAIN_
OFFSET, the POSTGAIN_OFFSET or both may be used to such
ends.
NS
Target poles aligned with
A1330 elements
E1 Pin 1 E2
Figure 34: Orientation of Magnet Relative to
Primary and Secondary Die
Magnet Misalignment
Magnetic misalignment with the A1330 package impacts the
linearity of the observed magnetic signal and consequently the
resulting accuracy. The influence of mechanical misalignment
may be minimized by reducing the overall airgap and by choos-
ing a larger magnet diameter. Figure 35 shows the influence of
magnet diameter of eccentricity error.
The dual die variant of the A1330 uses a stacked die approach,
resulting in a common eccentricity value for both die. This
eliminates the “native misalignment” present in “side-by-side”
packaging options.
0 0.5 1
1.5
Misalignment (mm)
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Angle Error
6.00 mm Diameter
8.00 mm Diameter
10.00 mm Diameter
Figure 35: Simulated Error versus Eccentricity for di󰀨erent size magnet diameters, at 2.0 mm air gap
Typical Systemic Error versus magnet to sensor eccentricity (daxial), Note: “Systemic Error” refers to application errors in alignment
and system timing. It does not refer to sensor IC device errors. The data in this graph is simulated with ideal magnetization.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
26
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Application Circuit Description
The analog output version of the A1330 may be operated with
either a pull-up or pull-down resistor. Use of a load resistor is
recommended, as this allows the output to float to a known “diag-
nostic” state in the event of a sensor diagnostic.
The PWM version, with its open-drain architecture, requires the
output be connected to a voltage source, through a load resistor.
Figure 36 shows a typical A1330 application circuit, for either
analog or PWM outputs. For EMC sensitive environments, an
output load capacitor of 2 nF is recommended
A1330
GND
VCC
VOUT
0.1 µF
Optional
2 nF Capacitor for EMC
10 kΩ
To ADC
VS
Regulated 5 V
Figure 36: Typical A1330 application circuit
ESD Performance
Under certain conditions, the ESD rating of the dual die IC may
be less than 2 kV if ground pins are not tied to a common node.
Contact Allegro for questions regarding ESD optimization.
Table 8: HBM ESD Rating (per AEC-Q100 002)
Package ESD Rating
TSSOP-08 (single die) 6 kV
TSSOP-08 (dual die) 6 kV [1]
[1] All GND pins shorted together.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
27
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
EEPROM MEMORY MAP
The EEPROM memory map is shown below.
All EEPROM may be read once the IC is in “Manchester Output Mode”. Writing requires the EEPROM lock bit to be clear, and appli-
cation of high voltage pulses on the output pin. See discussion on EEPROM programming for information on how to write EEPROM.
Table 9: EEPROM Memory Map
Address
Bits
31:26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10987654321 0
0x3A ECC R R PREGAIN_OFFSET Reserved Reserved
0x3B ECC SS Reserved GAIN
0x3C ECC CE ROE MAX_INPUT MIN_INPUT
0x3D ECC ABW PO POSTGAIN_OFFSET HIGH_CLAMP LOW_CLAMP
0x3E ECC EELO HYS_0 HYS PWM_FREQ ANG_AVE MISS_MAG_THRSH INTER TOR OVLO EED MAXA MINA MMF
0x3F ECC Customer Word
Bit 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10987654321 0
Name R R PREGAIN_OFFSET Reserved
Default0000000000000000000000000 0
Address 0x3A
PREGAIN_OFFSET [23:12]:
Pregain offset (zero adjust), at 12-bit resolution. This value is subtracted
from the measured angle value, independent of short stroke.
Value Description
0x0 to
0xFFF 0 to 359.91° subtracted from pre gain angle value.
Reserved [11:0]:
Reserved EEPROM registers. Should be set to 0’s.
Bit 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10987654321 0
Name SS Reserved GAIN
Default0000000000000000000000000 0
Address 0x3B
SS[25]:
Enables “short stroke” mode. Gain and Min/Max Input angle checking are
enabled.
Value Description
0 Short stroke not enabled
1 Short stroke enabled
Reserved[24:13]:
Reserved EEPROM registers. Should be set to 0’s.
GAIN[12:0]:
Sets gain to apply full dynamic range of the output for a limited input range.
Only applied if SS is set to ‘1’.
Applied gain is 1 plus the total value set in the Gain EEPROM field.
GAIN specified in 5.8, unsigned form.
Example:
GAIN field = 0x055A equates to 5 + (90 / 256) = 5.3515625
Applied gain = 1 + GAIN = 6.3515625
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
28
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Bit 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10987654321 0
Name CE ROE MAX_INPUT MIN_INPUT
Default0000000000000000000000000 0
Address 0x3C
CE[25]:
Clamp enable.
Value Description
0 Disabled clamps
1 Enables clamps
ROE[24]:
Roll-over enable.
Value Description
0 Disables roll-over
1 Enables roll-over
Both CE and ROE interact to create four distinct
operating modes. See table below.
CE ROE Description
0 0 Normal behavior.
Roll-over at standard module 360.
0 1 Output rolls-over at the High and Low
Clamp values.
1 0 Output clamps at the first encountered
High/Low Clamp value.
1 1
Roll-over occurs at standard module 360.
Output is clamped to High/Low Clamps
value.
MAX_INPUT[23:12]:
Sets the maximum input angle, after PREGAIN_OFFSET but before
scaling by GAIN. Used for short-stroke limit test, in 12-bit resolution units.
Setting this field to 0xFFF will effectively disable this feature. This allows
debugging and diagnostics of a possible broken sensor assembly. Used as
a diagnostic point if the angle exceeds the targeted dynamic range.
SS must be set to ‘1’ to enable this function.
Value Description
0x0 to
0xFFF Sets maximum input angle to 0 to 359.91°
MIN_INPUT[11:0]:
Sets the minimum input angle (after PREGAIN_OFFSET), but before scaling
by GAIN. Used for short-stroke limit test, in 12-bit resolution units. Setting
this field to 0 will effectively disable this feature. This allows debugging and
diagnostics of a possible broken sensor assembly. Used as a diagnostic
point if the angle decreases below the targeted dynamic range.
SS must be set to ‘1’ to enable this function.
Value Description
0x0 to
0xFFF Sets minimum input angle to 0 to 359.91°
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
29
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Bit 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10987654321 0
Name ABW PO POSTGAIN_OFFSET HIGH_CLAMP LOW_CLAMP
Default0000000000000000000000000 0
Address 0x3D
ABW[25]:
Analog back end BW. Sets the BW of the analog filter.
Value Description
0 30 kHz BW
1 15 kHz BW
PO[24]:
Polarity bit.
Sets which magnetic rotation direction results in an increasing output value.
If set to ‘0’, increasing angle is in the clockwise direction, when looking
down on the top of the die, from the magnets perspective.
This occurs prior to the PREGAIN_OFFSET.
Value Description
0Output angle increases with a clockwise rotation (when
viewed from above the magnet and device)
1Output angle increases with a counter-clockwise rotation
(when viewed from above the magnet and device)
POSTGAIN_OFFSET[23:12]:
Sets the output angular offset to relocate the 0° reference point for the
output angle. Applied after GAIN and Min/Max Input angle comparison.
Represented in signed 2’s complement.
Value Description
0x0 to
0x7FF 0° to 179.91°
0x800 to
0xFFF –180° to –0.088°
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
30
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
HIGH_CLAMP[11:6]:
Sets an output high angle clamp.
Applied after GAIN and POSTGAIN_OFFSET.
Decrements by ≈1% of VCC.
Code Voltage Approximate
Angle
Nominal
Voltage
Code Voltage Approximate
Angle
Nominal
Voltage
0 VOUT(MAX) 359.9 4.75 32 VOUT(MAX) –32% VCC 232.0 3.15
1 VOUT(MAX) – 1% VCC 356.0 4.70 33 VOUT(MAX) – 33% VCC 228.0 3.10
2 VOUT(MAX) – 2% VCC 351.9 4.65 34 VOUT(MAX) – 34% VCC 224.0 3.05
3 VOUT(MAX) – 3% VCC 348.0 4.60 35 VOUT(MAX) – 35% VCC 220.0 3.00
4 VOUT(MAX) – 4% VCC 343.9 4.55 36 VOUT(MAX) – 36% VCC 216.0 2.95
5 VOUT(MAX) – 5% VCC 340.0 4.50 37 VOUT(MAX) – 37% VCC 212.0 2.90
6 VOUT(MAX) – 6% VCC 335.9 4.45 38 VOUT(MAX) – 38% VCC 208.0 2.85
7 VOUT(MAX) – 7% VCC 332.0 4.40 39 VOUT(MAX) – 39% VCC 204.0 2.80
8 VOUT(MAX) – 8% VCC 327.9 4.35 40 VOUT(MAX) – 40% VCC 200.0 2.75
9 VOUT(MAX) – 9% VCC 324.0 4.30 41 VOUT(MAX) – 41% VCC 196.0 2.70
10 VOUT(MAX) – 10% VCC 319.9 4.25 42 VOUT(MAX) – 42% VCC 192.0 2.65
11 VOUT(MAX) – 11% VCC 316.0 4.20 43 VOUT(MAX) – 43% VCC 188.0 2.60
12 VOUT(MAX) – 12% VCC 311.9 4.15 44 VOUT(MAX) – 44% VCC 184.0 2.55
13 VOUT(MAX) – 13% VCC 308.0 4.10 45 VOUT(MAX) – 45% VCC 180.0 2.50
14 VOUT(MAX) – 14% VCC 303.9 4.05 46 VOUT(MAX) – 46% VCC 176.0 2.45
15 VOUT(MAX) – 15% VCC 300.0 4.00 47 VOUT(MAX) – 47% VCC 172.0 2.40
16 VOUT(MAX) – 16% VCC 295.9 3.95 48 VOUT(MAX) – 48% VCC 168.0 2.35
17 VOUT(MAX) – 17% VCC 292.0 3.90 49 VOUT(MAX) – 49% VCC 164.0 2.30
18 VOUT(MAX) – 18% VCC 287.9 3.85 50 VOUT(MAX) – 50% VCC 160.0 2.25
19 VOUT(MAX) – 19% VCC 284.0 3.80 51 VOUT(MAX) – 51% VCC 156.0 2.20
20 VOUT(MAX) – 20% VCC 279.9 3.75 52 VOUT(MAX) – 52% VCC 152.1 2.15
21 VOUT(MAX) – 21% VCC 276.0 3.70 53 VOUT(MAX) – 53% VCC 148.0 2.10
22 VOUT(MAX) – 22% VCC 271.9 3.65 54 VOUT(MAX) – 54% VCC 144.1 2.05
23 VOUT(MAX) – 23% VCC 268.0 3.60 55 VOUT(MAX) – 55% VCC 140.0 2.00
24 VOUT(MAX) – 24% VCC 263.9 3.55 56 VOUT(MAX) – 56% VCC 136.1 1.95
25 VOUT(MAX) – 25% VCC 260.0 3.50 57 VOUT(MAX) – 57% VCC 132.0 1.90
26 VOUT(MAX) – 26% VCC 255.9 3.45 58 VOUT(MAX) – 58% VCC 128.1 1.85
27 VOUT(MAX) – 27% VCC 252.0 3.40 59 VOUT(MAX) – 59% VCC 124.0 1.80
28 VOUT(MAX) – 28% VCC 247.9 3.35 60 VOUT(MAX) – 60% VCC 120.1 1.75
29 VOUT(MAX) – 29% VCC 244.0 3.30 61 VOUT(MAX) – 61% VCC 116.0 1.70
30 VOUT(MAX) – 30% VCC 240.0 3.25 62 VOUT(MAX) – 62% VCC 112.1 1.65
31 VOUT(MAX) – 31% VCC 236.0 3.20 63 VOUT(MAX) – 63% VCC 108.0 1.60
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
31
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
LOW_CLAMP [5:0]:
Sets an output low clamp level.
Applied after GAIN and POSTGAIN_OFFSET.
Increments by ≈1% of VCC.
Code Voltage Approximate
Angle
Nominal
Voltage
Code Voltage Approximate
Angle
Nominal
Voltage
0 VOUT(MIN) 0.0 0.25 32 VOUT(MIN) + 32% VCC 128.0 1.850
1 VOUT(MIN) + 1% VCC 4.0 0.30 33 VOUT(MIN) + 33% VCC 131.9 1.900
2 VOUT(MIN) + 2% VCC 8.0 0.35 34 VOUT(MIN) + 34% VCC 136.0 1.950
3 VOUT(MIN) + 3% VCC 12.0 0.40 35 VOUT(MIN) + 35% VCC 139.9 2.000
4 VOUT(MIN) + 4% VCC 16.0 0.45 36 VOUT(MIN) + 36% VCC 144.0 2.050
5 VOUT(MIN) + 5% VCC 20.0 0.50 37 VOUT(MIN) + 37% VCC 147.9 2.100
6 VOUT(MIN) + 6% VCC 24.0 0.55 38 VOUT(MIN) + 38% VCC 152.0 2.150
7 VOUT(MIN) + 7% VCC 27.9 0.60 39 VOUT(MIN) + 39% VCC 155.9 2.200
8 VOUT(MIN) + 8% VCC 32.0 0.65 40 VOUT(MIN) + 40% VCC 160.0 2.250
9 VOUT(MIN) + 9% VCC 35.9 0.70 41 VOUT(MIN) + 41% VCC 163.9 2.300
10 VOUT(MIN) + 10% VCC 40.0 0.75 42 VOUT(MIN) + 42% VCC 168.0 2.350
11 VOUT(MIN) + 11% VCC 43.9 0.80 43 VOUT(MIN) + 43% VCC 171.9 2.400
12 VOUT(MIN) + 12% VCC 48.0 0.85 44 VOUT(MIN) + 44% VCC 176.0 2.450
13 VOUT(MIN) + 13% VCC 51.9 0.90 45 VOUT(MIN) + 45% VCC 179.9 2.500
14 VOUT(MIN) + 14% VCC 56.0 0.95 46 VOUT(MIN) + 46% VCC 184.0 2.550
15 VOUT(MIN) + 15% VCC 59.9 1.00 47 VOUT(MIN) + 47% VCC 187.9 2.600
16 VOUT(MIN) + 16% VCC 64.0 1.05 48 VOUT(MIN) + 48% VCC 192.0 2.650
17 VOUT(MIN) + 17% VCC 67.9 1.10 49 VOUT(MIN) + 49% VCC 195.9 2.700
18 VOUT(MIN) + 18% VCC 72.0 1.15 50 VOUT(MIN) + 50% VCC 200.0 2.750
19 VOUT(MIN) + 19% VCC 75.9 1.20 51 VOUT(MIN) + 51% VCC 203.9 2.800
20 VOUT(MIN) + 20% VCC 80.0 1.25 52 VOUT(MIN) + 52% VCC 207.9 2.850
21 VOUT(MIN) + 21% VCC 83.9 1.30 53 VOUT(MIN) + 53% VCC 211.9 2.900
22 VOUT(MIN) + 22% VCC 88.0 1.35 54 VOUT(MIN) + 54% VCC 215.9 2.950
23 VOUT(MIN) + 23% VCC 91.9 1.40 55 VOUT(MIN) + 55% VCC 219.9 3.000
24 VOUT(MIN) + 24% VCC 96.0 1.45 56 VOUT(MIN) + 56% VCC 223.9 3.050
25 VOUT(MIN) + 25% VCC 99.9 1.50 57 VOUT(MIN) + 57% VCC 227.9 3.100
26 VOUT(MIN) + 26% VCC 104.0 1.55 58 VOUT(MIN) + 58% VCC 231.9 3.150
27 VOUT(MIN) + 27% VCC 107.9 1.60 59 VOUT(MIN) + 59% VCC 235.9 3.200
28 VOUT(MIN) + 28% VCC 112.0 1.65 60 VOUT(MIN) + 60% VCC 239.9 3.250
29 VOUT(MIN) + 29% VCC 115.9 1.70 61 VOUT(MIN) + 61% VCC 243.9 3.300
30 VOUT(MIN) + 30% VCC 120.0 1.75 62 VOUT(MIN) + 62% VCC 247.9 3.350
31 VOUT(MIN) + 31% VCC 123.9 1.80 63 VOUT(MIN) + 63% VCC 251.9 3.400
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
32
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Bit 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10987654321 0
Name EELO HYS_0 HYS PWM_FREQ ANG_AVE MISS_MAG_THRSH INTER TOR OVLO EED MAXA MINA MMF
Default 0 0* 0* 0 1 0 0 0* 0* 0* 0* 0* 0* 0* 0* 0* 1* 0* 1* 0 0 0 0 0 0 0
Address 0x3E
EELO[25]:
EEPROM Lock Bit.
Once set, EEPROM cannot be written.
Value Description
0 EEPROM writes allowed
1 EEPROM writing prevented
HYS_0[24]:
Hysteresis is only applied within ±11.16° of the 0/360 crossover point.
Value Description
0 Hysteresis is applied across the whole angle range
1 Hysteresis is only applied near the 0/360° crossover point
HYS[23:22]:
Hysteresis range selection.
When applied the angle will not update unless a change larger than the
hysteresis range is observed.
Applied after PREGAIN_OFFSET. Prior to GAIN.
* Default value of 0 for all catalog part numbers except A1330LLETR-T-C02.
Value Description
00 0°
01 0352°
10 0.703° (Default value for A1330LLETR-T-C02)
11 1.406°
PWM_FREQ[21:19]:
Sets the PWM carrier frequency.
PWM_FREQ PWM Frequency
000 20 kHz
001 10 kHz
010 5 kHz
011 2.5 kHz
100 1.25 kHz
101 625 Hz
110 312.5 Hz
111 156.25 Hz
ANG_AVE[18:16]:
Selects the number of internal angle samples to average. Reduces the
update rate of the IC for improved angle resolution.
* Default value of 0 for all catalog part numbers except
A1330LLETR-T-C02, which is set to 0112.
Value Quantity of Samples
Averaged Approx. Refresh Rate (µs)
000 1 25
001 2 50
010 4 100
011 8 200
100 16 400
101 32 800
110 64 1600
111 128 3200
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
33
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
MIS_MAG_THRSH[15:7]:
Threshold below which the missing magnet flag will assert. At Allegro
factory.
*This is programmed for a default of 100 G. The value of 01012 shown in
the above table is typical; actual values may vary, depending on device
behavior.
If a setting other than 100 G is desired, simply scale the existing value by
d_field / 100 where “d_field” is the desired trip point in gauss.
Example: If the desired trip point is 300 G, and the default factory EEPROM
value is 0x5, then the final value is 300 / 100 × 5 = 15 = 0xF.
INTER[6]:
Interpolator Error mask.
Prevents an interpolator error from setting the output to tri-state.
Value Description
0 Interpolator error will tri-state output
1 Interpolator error will not tri-state output
TOR[5]:
Temperature Out Of Range Mask.
Prevents a temperature out of range error from tri-stating the output.
Value Description
0 Temperature out of range error will tri-state output
1 Temperature out of rang error will not tri-state output
OVLO[4]:
Overvoltage Error Mask.
Prevents an overvoltage error from tristating the output.
Value Description
0 Overvoltage error will tri-state the output
1 Overvoltage error will not tri-state the output
EED[3]:
Dual bit EEPROM error.
Prevents a dual bit EEPROM error from tristating the output.
Value Description
0 Dual bit EEPROM error will tri-state the output
1 Dual bit EEPROM error will not tri-state the output
MAXA[2]:
Maximum Input Angle Mask.
When set, the output will not tri-state when the input angle exceeds the
MAX_INPUT value.
Value Description
0 Output tri-states if input angle exceeds MAX_INPUT
1 Output doesn’t tri-states if input angle exceeds MAX_INPUT
MINA[1]:
Minimum Input Angle Mask.
When set, the output will not tri-state when the input angle is below the
MIN_INPUT value.
Value Description
0 Output tri-states if input angle is below MIN_INPUT
1 Output doesn’t tri-states if input angle is below MIN_INPUT
MMF[0]:
Missing Magnet Flag Mask.
When set, output will not tri-state if the measured magnetic amplitude is
below the MIS_MAG_THRSH.
Value Description
0 Missing magnet error tri-states output
1 Missing magnet error does not tri-states output
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
34
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Bit 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10987654321 0
Name Customer Word
Default0000000000000000000000000 0
Address 0x3F
Customer Word[25:0]:
Customer EEPROM space.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
35
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Figure 37: Package LE, 8-Pin TSSOP (Single Die Version)
PACKAGE OUTLINE DRAWINGS
For Reference Only –Not for Tooling Use
(Reference MO-153AA)
Dimensions in millimeters - NOTTO SCALE
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
6.40 BSC
1.70
B
B
C
C
E
D
12
8
PCB Layout Reference View
Standard Branding Reference View
1
NNN
YYWW
A
= Last 3 digits of device part number
= Supplier emblem
= Last two digits of year of manufacture
= Week of manufacture
N
Y
W
Terminal #1 mark area
Reference land pattern layout (reference IPC7351 SOP65P640X110-8M);
all pads minimum of 0.20 mm from all adjacent pads; adjust as necessary
to meet application process requirements and PCB layout tolerances; when
mounting on a multilayer PCB, thermal vias can improve thermal dissipation
(reference EIA/JEDEC Standard JESD51-5)
Branding scale and appearance at supplier discretion
Hall element, not to scale
Active Area Depth = 0.36 mm REF
3.00 ±0.10
1.50
6.40 BSC 4.40 ±0.10
2.20
D
D
E
D
12
8
Branded Face
8X
0.10 C
0.30
0.19
0.65 BSC
0.25 BSC
0.15
0.05
1.10 MAX
SEATING
PLANE
C
8º
0º
0.02
0.09
0.60 1.00 REF
+0.15
-0.10
SEATING PLANE
GAUGE PLANE
A
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
36
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Figure 38: Package LE, 8-Pin TSSOP (Dual Die Version)
For Reference Only –Not for Tooling Use
(Reference MO-153AA)
Dimensions in millimeters - NOTTO SCALE
Dimensions exclusive of mold flash, gate burrs, and dambar protrusions
Exact case and lead configuration at supplier discretion within limits shown
6.40 BSC
1.70
B
B
C
C
E
D
12
8
PCB Layout Reference View
Standard Branding Reference View
1
NNN
YYWW
A
= Last 3 digits of device part number
= Supplier emblem
= Last two digits of year of manufacture
= Week of manufacture
N
Y
W
Terminal #1 mark area
Reference land pattern layout (reference IPC7351 SOP65P640X110-8M);
all pads minimum of 0.20 mm from all adjacent pads; adjust as necessary
to meet application process requirements and PCB layout tolerances; when
mounting on a multilayer PCB, thermal vias can improve thermal dissipation
(reference EIA/JEDEC Standard JESD51-5)
Branding scale and appearance at supplier discretion
Hall element (D1, D2), not to scale
ActiveArea Depth; 0.27 mm (die 1), 0.43 mm (die 2)
3.00 ±0.10
1.40
6.40 BSC 4.40 ±0.10
2.18
D
D
E
12
8
Branded Face
8×
0.10 C
0.30
0.19
0.65 BSC
0.25 BSC
0.15
0.05
1.10 MAX
SEATING
PLANE
C
8º
0º
0.02
0.09
0.60 1.00 REF
+0.15
-0.10
SEATING PLANE
GAUGE PLANE
A
D1
2.27 D
D2
D2
1.60
D
D1
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
A-1
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
APPENDIX A: ANGLE ERROR AND DRIFT DEFINITION
Angle error is the difference between the actual position of the
magnet and the position of the magnet as measured by the angle
sensor IC (without noise). This measurement is done by reading
the angle sensor IC output and comparing it with a high resolu-
tion encoder (refer to Figure 39).
Angle Error
E [º]
E =–
Sensor Real
E
max
E–E
max min
E
minl
0º
360º
Reference
Angle
Real
Figure 39: Angle Error Denition
Angle Error Definition
Throughout this document, the term “angle error” is used exten-
sively. Thus, it is necessary to introduce a single angle error
definition for a full magnetic rotation. The term “angle error” is
calculated according to the following formula:
maxmin
AngleError
EE
2
–
=
In other words, it is the amplitude of the deviation from a perfect
straight line between 0 and 360 degrees. For the purposes of a
generic definition, the offset of the IC angle profile is removed
prior to the error calculation (this can be seen in Figure 39). The
offset itself will depend on the starting IC angle position relative
to the encoder 0° and thus can differ anywhere from 0-360°.
Angle Drift
Angle drift is the change in the observed angular position over
temperature, relative to 25°C.
During Allegro’s factory trim, drift is measured at 150°C. The
value is calculated using the following formula:
AngleDrift = Angle25°C – Angle150°C
where each Angle value is an array corresponding to 16 angular
positions around a circle.
Reference Angle
Ideal
Angle Error (Deg)
Angle Drift of 150°C in Reference to 25°C
Error 25°C
Error 150°C
No Error
Drift of data point 1
Drift of data point 2
Figure 40: Angle Drift of 150°C in Reference to 25°C [1]
[1] Note that the data above is simply a representation of angle
drift and not real data.
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
A-2
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Ratiometry Error Definition
The analog version of the A1330 provides a ratiometric output.
This means that the Voltage Output, VOUT, and the angular sensi-
tivity 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 5.0 V, and the measured
change in each characteristic.
The ratiometric error for a given magnetic position (θ),
RatVOUT (%), for a given supply voltage, VCC, is defined as:
V
OUT(θ)(VCC) / V
OUT(θ)(5.0V)
V
CC / 5.0 (V)
1–
RatVOUT(θ) =×
100 (%)
clockwisecounter-clockwise
VSAT(Low)
VSAT(High)
Output Voltage, VOUT (V)
Appied Magnetic Field Angle
180°
Figure 41: E󰀨ect of Saturation
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
B-1
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
APPENDIX B: CRC DOCUMENATION
Manchester CRC Implementation
The 3-bit Manchester CRC can be calculated using the following
C code:
// command: the manchester command, right justified, does
not include the space for the CRC
// numberOfBits: number of bits in the command not includ-
ing the 2 zero sync bits at the start of the command and the
three CRC bits
// Returns: The three bit CRC
// This code can be tested at http://codepad.org/yqTKnfmD
uint16_t ManchesterCRC(uint64_t data, uint16_t numberOfBits)
{
bool C0 = false;
bool C1 = false;
bool C2 = false;
bool C0p = true;
bool C1p = true;
bool C2p = true;
uint64_t bitMask = 1;
bitMask <<= numberOfBits - 1;
// Calculate the state machine
for (; bitMask != 0; bitMask >>= 1)
{
C2 = C1p;
C0 = C2p ^ ((data & bitMask) != 0);
C1 = C0 ^ C0p;
C0p = C0;
C1p = C1;
C2p = C2;
}
return (C2 ? 4U : 0U) + (C1 ? 2U : 0U) + (C0 ? 1U :
0U);
}
Programmable Angle Sensor IC
with Analog and PWM Output
A1330
B-2
Allegro MicroSystems, LLC
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Revision History
Revision Date Description
– September 25, 2017 Initial release
1 June 29, 2018
Updated Features and Benefits (page 1), Thermal Characteristics (page 2), Supply Current (page 5),
Figure 3 and 4 (page 7), Figures 14 through 17 (page 19 and 21), Gain section (page 20), Clamp and
Roll-Over Logic figure captions (page 21), Figures 32 and 33 (page 24), Figure 34 (page 25), and Dual
Die LE-8 Package Drawing active area depth dimensions (page 36); added figure to Angle Averaging
section (page 18).
2 August 3, 2018 Updated Features and Benefits (page 1), Selection Guide (page 2), Response Time (page 6), Angle
Noise (page 6), Figure 3 (page 7), Hysteresis (page 10), Address 0x3E (page 32-33).
For the latest version of this document, visit our website:
www.allegromicro.com
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