AS5261 Datasheet

high
performance
needs great
design.
Datasheet: AS5261 12-Bit Automotive Angle Position Sensor
Please be patient while we update our brand image as
austriamicrosystems and TAOS are now ams.
www.ams.com
AS5261
12-Bit Automotive Angle Position Sensor
1 General Description
2 Key Features
The AS5261 is a contactless magnetic angle position sensor for
accurate angular measurement over a full turn of 360°. A sub range
can be programmed to achieve the best resolution for the
application. It is a system-on-chip, combining integrated Hall
elements, analog front end, digital signal processing and best in
class automotive protection features in a single device.
360º contactless high resolution angular position encoding
To measure the angle, only a simple two-pole magnet, rotating over
the center of the chip, is required. The magnet may be placed above
or below the IC.
Wide temperature range: - 40ºC
The absolute angle measurement provides instant indication of the
magnet’s angular position with a resolution of 0.022° = 16384
positions per revolution. According to this resolution the adjustment
of the application specific mechanical positions are possible. The
angular output data is available over a 12 bit PWM output.
The AS5261 operates at a supply voltage of 5V and the supply and
output pins are protected against overvoltage up to +20V. In addition
the supply pins are protected against reverse polarity up to –20V.
Figure 1. Typical Arrangement of AS5261 and magnet
User programmable start and end point of the application region
+ linearization.
User programmable clamping levels and programming of the
transition point.
to + 150ºC
Small Pb-free package: MLF 16 6x6 (with dimple)
Broken GND and VDD detection
3 Benefits
Unique fully differential solution
Best protections for automotive applications
Easy to program
Additional linearization points for output characteristic
Ideal for applications in harsh environments due to contactless
position sensing
Robust system, tolerant to magnet misalignment, air gap
variations, temperature variations and external magnetic fields
High inherent accuracy
Stacked die redundant approach
4 Applications
The AS5261 is ideal for automotive applications like throttle and
valve position sensing, gearbox position sensor, pedal position
sensing and contactless potentiometers.
www.ams.com
Revision 1.1
1 - 32
AS5261
Datasheet - A p p l i c a t i o n s
Figure 2. AS5261 Block Diagram
VDD3V3_T
VDD_T
VDD_B
VDD3V3_B
High Voltage/
Reverse Polarity
Protection
Hall Array
Frontend
Amplifier
ADC
AS5261
Sin
Cos
DSP
CORDIC
Controller
12
Single Pin
Interface
(UART)
PWM
OUT_T
LS Driver
OUT_B
OTP Register
(Programming
Parameters)
GND_B
www.ams.com
GND_T
Revision 1.1
2 - 32
AS5261
Datasheet - C o n t e n t s
Contents
1 General Description ..................................................................................................................................................................
1
2 Key Features.............................................................................................................................................................................
1
3 Benefits.....................................................................................................................................................................................
1
4 Applications...............................................................................................................................................................................
1
5 Pin Assignments .......................................................................................................................................................................
4
5.1 Pin Descriptions....................................................................................................................................................................................
4
6 Absolute Maximum Ratings ......................................................................................................................................................
5
7 Electrical Characteristics...........................................................................................................................................................
6
7.1 Operating Conditions............................................................................................................................................................................
6
7.2 Magnetic Input Specification.................................................................................................................................................................
6
7.3 Electrical System Specifications...........................................................................................................................................................
7
7.4 Timing Characteristics ..........................................................................................................................................................................
7
8 Detailed Description..................................................................................................................................................................
8
8.1 Operation..............................................................................................................................................................................................
8
8.1.1 VDD Voltage Monitor ................................................................................................................................................................... 8
8.2 PWM Output .........................................................................................................................................................................................
8.2.1
8.2.2
8.2.3
8.2.4
8.2.5
8.2.6
8.2.7
8.2.8
8
Programming Parameters............................................................................................................................................................ 9
Application Specific Angular Range Programming ...................................................................................................................... 9
Application Specific Programming of the Break Point ............................................................................................................... 10
Multiple Slope Output ................................................................................................................................................................ 10
Linearization of the Output......................................................................................................................................................... 12
Resolution of Parameters .......................................................................................................................................................... 12
Noise Suppressor ...................................................................................................................................................................... 14
Hysteresis Function ................................................................................................................................................................... 14
8.3 PWM Output Driver Parameters.........................................................................................................................................................
9 Application Information ...........................................................................................................................................................
14
15
9.1 Recommended Application Schematic...............................................................................................................................................
15
9.2 Programming the AS5261 ..................................................................................................................................................................
15
9.2.1
9.2.2
9.2.3
9.2.4
9.2.5
UART Interface for Programming ..............................................................................................................................................
Frame Organization ...................................................................................................................................................................
READ.........................................................................................................................................................................................
WRITE .......................................................................................................................................................................................
Baud Rate Setup .......................................................................................................................................................................
16
16
17
17
18
9.3 OTP Programming Data .....................................................................................................................................................................
19
9.4 READ / WRITE Register Map.............................................................................................................................................................
23
9.5 READ Only Register Map...................................................................................................................................................................
24
9.6 Special Registers................................................................................................................................................................................
26
9.7 Programming Procedure ....................................................................................................................................................................
27
10 Package Drawings and Markings .........................................................................................................................................
28
11 Ordering Information .............................................................................................................................................................
31
www.ams.com
Revision 1.1
3 - 32
AS5261
Datasheet - P i n A s s i g n m e n t s
5 Pin Assignments
Figure 3. MLF-16 Pin Configuration (View from Top)
OUT_T
2
OUT_B
TP1_B
VDD_T
1
VDD_B
TP1_T
16
15
14
13
12 S_B
11 S_T
Epad
VDD3V3_T
3
10 TP3_B
VDD3V3_B
4
9
5
6
7
8
TP3_T
GND_T
GND_B
TP2_T
TP2_B
5.1 Pin Descriptions
Table 1. MLF-16 Pin Descriptions
Pin Number
Pin Name
Pin Type
Description
1
TP1_T
Test pin for fabrication. Connected to ground in the application.
2
TP1_B
DIO/AIO
Multi purpose pin
3
VDD3V3_T
4
VDD3V3_B
5
GND_T
6
GND_B
7
TP2_T
8
TP2_B
9
TP3_T
10
TP3_B
Test pin for fabrication. Left open in the application.
11
S_T
Test pin for fabrication. Connected to OUT_T in the application.
( special case for the connection possible → 4-wire mode)
12
S_B
13
OUT_T
14
OUT_B
15
VDD_T
16
VDD_B
Output of the LDO. 1µF required.
AIO
Supply pin
Output of the LDO. 1µF required.
Ground pin. Connected to ground in the application.
Ground pin. Connected to ground in the application.
Test pin for fabrication. Connected to ground in the application.
DIO/AIO
Multi purpose pin
AIO
www.ams.com
Test pin for fabrication. Connected to ground in the application.
Digital output/Digital
PWM output
Supply pin
Test pin for fabrication. Connected to ground in the application.
Test pin for fabrication. Left open in the application.
Test pin for fabrication. Connected to OUT_B in the application.
( special case for the connection possible → 4-wire mode)
PWM output pin. Open drain configuration. Programming pin.
PWM output pin. Open drain configuration. Programming pin.
Positive supply pin. This pin is over voltage protected.
Positive supply pin. This pin is over voltage protected.
Revision 1.1
4 - 32
AS5261
Datasheet - A b s o l u t e M a x i m u m R a t i n g s
6 Absolute Maximum Ratings
Stresses beyond those listed in Table 2 may cause permanent damage to the device. These are stress ratings only, and functional operation of
the device at these or any other conditions beyond those indicated in Electrical Characteristics on page 6 is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
Table 2. Absolute Maximum Ratings
Symbol
Parameter
Min
Max
Units
Comments
DC supply voltage at pin VDD
Overvoltage
-20
20
V
No operation
Permanent
Electrical Parameters
VDD
VOUT
Output voltage OUT
-0.3
20
V
VDD3V3
DC supply voltage at pin VDD3V3
-0.3
5
V
Iscr
Input current (latchup immunity)
-100
100
mA
Norm: AEC-Q100-004
±2
kV
Norm: AEC-Q100-002
+150
ºC
Min -67ºF; Max +257ºF
260
ºC
The reflow peak soldering temperature (body
temperature) specified is in accordance with
IPC/JEDEC J-STD-020 “Moisture/Reflow
Sensitivity Classification for Non-Hermetic Solid
State Surface Mount Devices”. The lead finish
for Pb-free leaded packages is matte tin (100%
Sn).
85
%
Electrostatic Discharge
ESD
Electrostatic discharge
Temperature Ranges and Storage Conditions
Tstrg
Storage temperature
TBody
Body temperature
H
Humidity non-condensing
MSL
Moisture Sensitive Level
www.ams.com
-55
5
3
Revision 1.1
Represents a maximum floor life time of 168h
5 - 32
AS5261
Datasheet - E l e c t r i c a l C h a r a c t e r i s t i c s
7 Electrical Characteristics
7.1 Operating Conditions
In this specification, all the defined tolerances for external components need to be assured over the whole operation conditions range and also
over lifetime.
Table 3. Operating Conditions
Symbol
Parameter
Conditions
Min
TAMB
Ambient temperature
-40ºF…+302ºF
-40
Isupp
Supply current
Only for one die. Must be multiplied by 2
VDD
Supply voltage at pin VDD
Typ
Max
Units
+150
ºC
10
mA
4.5
5.0
5.5
V
Typ
Max
Units
7.2 Magnetic Input Specification
TAMB = -40 to +150ºC, VDD = 4.5 to 5.5V (5V operation), unless otherwise noted.
Two-pole cylindrical diametrically magnetized source:
Table 4. Magnetic Input Specification
Symbol
Parameter
Conditions
Min
Bpk
Magnetic input field amplitude
Required vertical component of the
magnetic field strength on the die’s surface,
measured along a concentric circle with a
radius of 1.25 mm
30
70
mT
Bpkext
Magnetic input field amplitude
(extended) default setting
Required vertical component of the
magnetic field strength on the die’s surface,
measured along a concentric circle with a
radius of 1.25 mm. Increased sensor output
noise.
10
90
mT
Boff
Magnetic offset
Constant magnetic stray field
±5
mT
Disp
Displacement radius
Offset between defined device center and
magnet axis. Dependent on the selected
magnet. Including Eccentricity.
www.ams.com
Revision 1.1
1
mm
6 - 32
AS5261
Datasheet - E l e c t r i c a l C h a r a c t e r i s t i c s
7.3 Electrical System Specifications
TAMB = -40 to +150ºC, VDD = 4.5 - 5.5V (5V operation), Magnetic Input Specification, unless otherwise noted.
Table 5. Electrical System Specifications
Symbol
Parameter
RES
Resolution PWM Output
INLopt
Max
Units
Range > 90º
12
bit
Integral non-linearity (optimum)
Best aligned reference magnet at 25ºC
over full turn 360º.
0.5
deg
INLtemp
Integral non-linearity (optimum)
Best aligned reference magnet over
temperature -40 -150º over full turn 360º.
0.9
deg
INL
Integral non-linearity
Best aligned reference magnet over
temperature -40 -150º over full turn 360º
and displacement
1.4
deg
ONF0
At 14 bit angular information, 360º mode.
Internal Filter disabled.
±5
LSB
ONF1
At 14 bit angular information, 360º mode.
Filter setting 1.
±3
LSB
ONF2
At 14 bit angular information, 360º mode.
Filter setting 2.
±2
LSB
ONF3
At 14 bit angular information, 360º mode.
Filter setting 3. Jitter free.
±0.5
LSB
10
ms
300
µs
Max
Units
12
ms
Output Noise
tPwrUp
Power-up time 0-5V
tdelay
System propagation delay
absolute output: delay of ADC,
DSP and absolute interface
Conditions
Min
Typ
Power up time 5V operation. Default Power
up.
7.4 Timing Characteristics
Table 6. Timing Conditions
Symbol
Parameter
TDETWD
WachDog error detection time
www.ams.com
Conditions
Revision 1.1
Min
Typ
7 - 32
AS5261
Datasheet - D e t a i l e d D e s c r i p t i o n
8 Detailed Description
The AS5261 is manufactured in a CMOS process and uses a spinning current Hall technology for sensing the magnetic field distribution across
the surface of the chip. This IC consists of two galvanic isolated dies. All following in and register names refers to one die.
The integrated Hall elements are placed around the center of the device and deliver a voltage representation of the magnetic field at the surface
of the IC.
Through Sigma-Delta Analog / Digital Conversion and Digital Signal-Processing (DSP) algorithms, the AS5261 provides accurate high-resolution
absolute angular position information. For this purpose a Coordinate Rotation Digital Computer (CORDIC) calculates the angle and the
magnitude of the Hall array signals.
The DSP is also used to provide digital information at the outputs that indicate movements of the used magnet towards or away from the device’s
surface.
A small low cost diametrically magnetized (two-pole) standard magnet provides the angular position information.
The AS5261 senses the orientation of the magnetic field and calculates a 14-bit binary code. This code is mapped to a programmable output
characteristic in a PWM duty cycle format. This signal is available at the pin (OUT).
The application angular region can be programmed in a user friendly way. The start angle position T1 and the end point T2 can be set and
programmed according the mechanical range of the application with a resolution of 14 bits. In addition the T1Y and T2Y parameter can be set
and programmed according the application. The transition point 0 to 360 degree can be shifted using the break point parameter BP. The voltage
for clamping level low CLL and clamping level high CLH can be programmed with a resolution of 9 bits. Both levels are individually adjustable.
Two additional linearization points can be used to improve the system linearity. These points C1 and C2 are programmable.
The output parameters can be programmed in an OTP register. No additional voltage is required to program the AS5261. The setting may be
overwritten at any time and will be reset to default when power is cycled. To make the setting permanent, the OTP register must be programmed
by using a lock bit the content could be frozen for ever.
The AS5261 is tolerant to magnet misalignment and unwanted external magnetic fields due to differential measurement technique and Hall
sensor conditioning circuitry.
8.1 Operation
8.1.1
VDD Voltage Monitor
VDD Over Voltage Management. If the voltage applied to the VDD pin exceeds the over-voltage upper threshold for longer than the
detection time the output is turned off. When the over voltage event has passed and the voltage applied to the VDD pin falls below the overvoltage lower threshold for longer than the recovery time the device enters the normal mode and the output is enabled.
VDD Under Voltage Management. When the voltage applied to the VDD pin falls below the under-voltage lower threshold for longer than
the detection time the output is turned off. When the voltage applied to the VDD pin exceeds the under-voltage upper threshold for longer than
the detection time the device enters the normal mode and the output is enabled.
8.2 PWM Output
By default (after programmed CUST_LOCK OTP bit) the PWM output mode is selected. The pin OUT provides a modulated signal that is
proportional to the angle of the rotating magnet. Due to an intelligent approach a permanent short circuit will not damage the device. This is also
feasible in a high voltage condition up to 20 V and at the highest specified ambient temperature.
After the digital signal processing (DSP) a PWM engine provides the output signal.
The DSP maps the application range to the output characteristic. An inversion of the slope is also programmable to allow inversion of the rotation
direction.
An on-chip diagnostic feature handles the error state at the output. Depending on the failure the output is in HiZ condition or indicates a PWM
signal within the failure bands of 4 – 96 % duty cycle. (see Table 8)
www.ams.com
Revision 1.1
8 - 32
AS5261
Datasheet - D e t a i l e d D e s c r i p t i o n
8.2.1
Programming Parameters
The PWM output characteristic is programmable by OTP. Depending on the application, the output can be adjusted. The user can program the
following application specific parameters:
T2
Mechanical angle start point
Mechanical angle end point
T1Y
% duty cycle level at the T1 position
T2Y
% duty cycle level at the T2 position
CLL
Clamping Level Low
CLH
Clamping Level High
BP
Break point (transition point 0 to 360º)
C1
Calibration Point 1
C2
Calibration Point 2
C1Y
Trim value for C1
C2Y
Trim value for C2
T1
These parameters are input parameters. Using the available programming software and programmer these parameters are converted and finally
written into the AS5261 128 bit OTP memory.
8.2.2
Application Specific Angular Range Programming
The application range can be selected by programming T1 with a related T1Y and T2 with a related T2Y into the AS5261. The clamping levels
CLL and CLH can be programmed independent from the T1 and T2 position and both levels can be separately adjusted.
Figure 4. Programming of an Individual Application Range
Figure 4 shows a simple example of the selection of the range. The mechanical starting point T1 and the mechanical end point T2 are defining
the mechanical range. A sub range of the internal Cordic output range is used and mapped to the needed output characteristic. The PWM output
signal has 12 bit, hence the level T1Y and T2Y can be adjusted with this resolution. As a result of this level and the calculated slope the clamping
region low is defined. The break point BP defines the transition between CLL and CLH. In this example the BP is set to 0º. The BP is also the
end point of the clamping level high CLH. This range is defined by the level CLH and the calculated slope. Both clamping levels can be set
independently form each other. The minimum application range is 9.8º.
www.ams.com
Revision 1.1
9 - 32
AS5261
Datasheet - D e t a i l e d D e s c r i p t i o n
8.2.3
Application Specific Programming of the Break Point
The break point BP can be programmed as well with 14 bits. This is important when the default transition point is inside the application range. In
such a case the default transition point must be shifted out of the application range. The parameter BP defines the new position.
Figure 5. Individual Programming of the Break Point BP
8.2.4
Multiple Slope Output
The AS5261 can be programmed to multiple slopes. Where one programmed reference slope characteristic is copied to multiple slopes. Two,
three and four slopes are selectable by the user OTP bits QUADEN (1:0). In addition to the steepness of the slope the clamping levels can be
programmed as well.
Figure 6. Two Slope Mode
Duty Cycle
100 % DC
0
www.ams.com
360
Revision 1.1
10 - 32
AS5261
Datasheet - D e t a i l e d D e s c r i p t i o n
Figure 7. Four Slope Mode
Duty Cycle
100 % DC
0
www.ams.com
360
Revision 1.1
11 - 32
AS5261
Datasheet - D e t a i l e d D e s c r i p t i o n
8.2.5
Linearization of the Output
To improve the system linearity an additional 2 point linearization function is implemented in the AS5261.
Figure 8. Linearization of the Output Characteristic
100%DC
CLH
T2Y
C2Y
C1Y
T1Y
CLL
0
T1
8.2.6
C1
C2
T2
Resolution of Parameters
The programming parameters have a wide resolution of up to 14 bits.
Table 7. Resolution of the Programming Parameters
Symbol
Parameter
Resolution
T1
Mechanical angle start point
14 bits
T2
Mechanical angle stop point
14 bits
T1Y
Mechanical start voltage level
12 bits
T2Y
Mechanical stop voltage level
12 bits
CLL
Clamping level low
9 bits
CLH
Clamping level high
9 bits
BP
Break point
14 bits
C1
Calibration Point 1
4 bits
C2
Calibration Point 2
4 bits
C1Y
Trim value C1
3 bits
C2Y
Trim value C2
3 bits
www.ams.com
Revision 1.1
Note
12 - 32
AS5261
Datasheet - D e t a i l e d D e s c r i p t i o n
Figure 9. Overview Output Range
100
96
Failure Band High
Clamping Region High
Duty Cycle
CLH
Application Region
CLL
Clamping Region Low
4
0
Failure Band Low
Figure 9 gives an overview about the different ranges. The failure bands are used to indicate a wrong operation of the AS5261. This can be
caused due to a broken supply line. By using the specified load resistors the output level will remain in these bands during a fail. It is
recommended to set the clamping level CLL above the lower failure band and the clamping level CLH below the higher failure band.
CLOAD ≤ 33 nF, RPU= 1k…10kΩ
www.ams.com
Revision 1.1
13 - 32
AS5261
Datasheet - D e t a i l e d D e s c r i p t i o n
Table 8. Different Failure Cases of AS5261
Type
Internal alarms (failures)
Application related
failures
Failure Mode
Symbol
Failure Band
Note
Out of magnetic range
(too less or too high magnetic input)
MAGRng
High/Low
Programmable by OTP bit DIAG_HIGH
Cordic overflow
COF
High/Low
Programmable by OTP bit DIAG_HIGH
Offset compensation finished
OCF
High/Low
Programmable by OTP bit DIAG_HIGH
Watchdog fail
WDF
High/Low
Programmable by OTP bit DIAG_HIGH
Oscillator fail
OF
High/Low
Programmable by OTP bit DIAG_HIGH
Overvoltage condition
OV
Broken VDD
BVDD
Broken VSS
BVSS
Short circuit output
SCO
High
Dependant on the load resistor
Pull up → failure band high
High
Switch off → short circuit dependent
For efficient use of diagnostics, it is recommended to program to clamping levels CLL and CLH.
8.2.7
Noise Suppressor
The noise suppressor is inserted on two levels of the DSP chain. The first stage, on the output of the Cordic block, is capable to reduce the noise
level up to 1 LSB peak to peak. The second stage, on the output of the straight-line tracer, reduces the impact of the post processing. In fact
depending on the programmed operating angular sector the gain module amplifies also the noise level up to 8 LSB peak to peak and the second
stage of the noise suppressor reduces it again to 1 LSB peak to peak.
Four possible configurations of the noise suppressor can be selected via the OTP bits FILTERCFG<1:0>.
8.2.8
Hysteresis Function
AS5261 device includes a hysteresis function to avoid sudden jumps from CLH to CLL and vice versa caused by noise in the full turn
configuration.
The hysteresis amplitude can be selected via the OTP bits HYSTSEL<1:0>.
8.3 PWM Output Driver Parameters
The output stage is configured in a open drain output.
The PWM duty cycle represents the angular output data. All programming features are available for the PWM mode as well. The PWM period is
programmable in four steps and can be programmed by PWMF<2:0>.
CLOAD≤ 33 nF, RPU= 1k…10kΩ
Table 9. PWM Parameters Output Driver
Symbol
Parameter
Conditions
Min
Typ
Max
Units
PWMF1
PWM frequency 7
PWMF<2:0>=111
109.86
122
134.28
Hz
PWMF2
PWM frequency 6
PWMF<2:0>=110
179.78
200
219.73
Hz
PWMF3
PWM frequency 5
PWMF<2:0>=101
219.73
244
268.55
Hz
PWMF4
PWM frequency 4
PWMF<2:0>=100
329.59
366
402.83
Hz
PWMF5
PWM frequency 3
PWMF<2:0>=011
494.38
549
604.25
Hz
PWMF6
PWM frequency 2
PWMF<2:0>=010
659.18
732
805.66
Hz
PWMF7
PWM frequency 1
PWMF<2:0>=001
988.77
1100
1208.50
Hz
PWMF8
PWM frequency 0
PWMF<2:0>=000
1977.54
2197
2416.2
Hz
PWMDC
PWM duty cycle range
info parameter
4
96
%
PWMVOL
Output voltage low
IOUT=5mA
0
0.4
V
PWMSRF
PWM slew rate (falling edge)
Between 75% and 25%
RPUOUT=4KΩ; CLOUT=1nF
VDD=5V
1
4
V / µs
www.ams.com
Revision 1.1
2
14 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9 Application Information
9.1 Recommended Application Schematic
Figure 10 shows the recommended schematic in the application. All components marked with (*) are optional and can be used to further
increase the EMC.
Figure 10. AS5261 6-Wire Connection with Pull-Up Resistors
Sensor PCB
Electric Control Unit
VDD1
VDD2
R1_x*
R2_x*
TP1_T
TP1_B
VDD3V3_T
C2_x
VDD3V3_B
15
14
12
11
AS5261
3
RLPU_B
13
1
2
RLPU_T
OUT1
OUT_T
C4_x*
OUT_B
VDD_T
VDD_B
16
C1_x
OUT2
10
4
9
5
6
7
8
S_B
S_T
TP3_B
C3_x
CL_T
CL_B
TP3_T
GND_T
GND_B
TP2_T
TP2_B
GND1
GND2
Table 10. External Components
Symbol
Parameter
Min
Typ
Max
Unit
Note
C1
VDD buffer capacitor
0.8
1
1.2
µF
Low ESR 0.3 Ω
C2
VDD3V3 regulator capacitor
0.8
1
1.2
µF
Low ESR 0.3 Ω
C3
OUT load capacitor (sensor PCB)
0
4.7
nF
C4
R1
*
VDD capacitor (optional)
4.7
nF
*
VDD serial resistor (optional)
10
Ω
CL
R2
*
RLPU
OUT load capacitor (ECU)
0
OUT serial resistor (optional)
OUT pull-up resistance
33
nF
Ω
50
4
Do not increase due to
programming over output.
10
kΩ
9.2 Programming the AS5261
The AS5261 programming is a one-time-programming (OTP) method, based on polysilicon fuses. The advantage of this method is that no
additional programming voltage is needed. The internal LDO provides the current for programming.
The OTP consists of 128 bits; several bits are available for user programming. In addition factory settings are stored in the OTP memory. Both
regions are independently lockable by build in lock bits.
A single OTP cell can be programmed only once. Per default, the cell is “0”; a programmed cell will contain a “1”. While it is not possible to reset
a programmed bit from “1” to “0”, multiple OTP writes are possible, as long as only unprogrammed “0”-bits are programmed to “1”.
Independent of the OTP programming, it is possible to overwrite the OTP register temporarily with an OTP write command. This is possible only
if the user lock bit is not programmed.
www.ams.com
Revision 1.1
15 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
Due to the programming over the output pin the device will initially start in the communication mode. In this mode the digital angle value can be
read with a specific protocol format. It is a bidirectional communication possible. Parameters can be written into the device. A programming of the
device is triggered by a specific command. With another command (pass2func) the device can be switched into operation mode. In case of a
programmed user lock bit the AS5261 automatically starts up in the functional operation mode. No communication of the specific protocol is
possible after this.
A standard half duplex UART protocol is used to exchange data with the device in the communication mode.
9.2.1
UART Interface for Programming
The AS5261 uses a standard UART interface with a byte for address and two bytes for the data content. The read or write mode is selected in
the first byte. An even parity for every byte. The timing (baudrate) is selected by the AS5261 over an initial command from the master. The baud
rate register can be read and overwritten. The keep synchronization it AS5261 synchronizes art every Start bit. This happens during a standard
write access 3 times.
A time out function detects not complete commands and resets the AS5261 UART after the timeout period.
9.2.2
Frame Organization
Each frame is composed by 24 bits. The first byte (Address or Command) of the frame specifies the read/write operation with the register
address or is used for a command. 16 data bits contains the communication data. There will be no operation in case of the usage of a not
specified CMD. The UART programming interface block of the AS5261 can operate in slave communication or master communication mode. In
the slave communication mode the AS5261 receives the data. The programming tool is the driver of the single communication line. In case of the
master comunication mode the AS5261 transmits data in the frame format. The single communication line can be pulled down by the AS5261.
Table 11. OTP Commands and Communication
Possible Interface
Commands
Address / Command
AS5X63 Communication
Mode
WRITE
0x00-0x0F (OTP)
0x10-0x1F (SFR)
0x20-0xFF (Special Mode)
SLAVE
Write related to the address the user data
READ
0x00-0x0F (OTP)
0x10-0x1F (SFR)
0x20-0xFF (Special Mode)
SLAVE and MASTER
Read related to the address the user data
FUSE
0x22+ key
SLAVE
Command for permanent programming
PASS2FUNC
0x23+ key
SLAVE
Change operation mode from communication to
operation
www.ams.com
Revision 1.1
Description
16 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.2.3
READ
Figure 11 shows the format of the frame:
High Byte
S
P
AS5261 in Receiving
Mode
IDLE
Even Parity
Stop
Even Parity
Stop
Break
Start
P
MSB
LSB
Low Byte
S
R/Wn
Even Parity
Stop
Break
Start
P
MSB
LSB
Reg. Address
S
Start
IDLE
MSB
LSB
Figure 11. Organization of the READ Command
AS5261 in transmitting mode (Read
Access)
The R/Wn bit in the first byte selects the mode. Between the data packets is always a break state. The break state has the same length as the
other data bits.
An even parity bit is used to guarantee a correct data transmission. The parity bit is generated by the 8 bits.
9.2.4
WRITE
Figure 12 shows the format of the frame:
MSB
P
Even Parity
Stop
LSB
MSB
P
High Byte
S
Even Parity
Stop
Break
Start
Low Byte
S
R/n
Even Parity
Stop
Break
Start
P
AS5261 in Receiving
Mode
www.ams.com
LSB
Reg. Address
S
Start
IDLE
MSB
LSB
Figure 12. Organization of the READ Command
IDLE
AS5261 in Receiving Mode (Write Access)
Revision 1.1
17 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.2.5
Baud Rate Setup
Due to the internal RC oscillator the AS5261 needs to synchronize to the master. This happens after startup with the first baud rate command.
This register address is reserved after the first successful setup for a possible manual setting of the baud rate.
1
0
IDLE
1
0
1
0
1
0
P
0x55 » „U“ will be send from
Master to Setup Baudrate of
AS5261
Low Byte
S
P
Even Parity
Stop
Break
Start
0
LSB
MSB
LSB
Baud Command
S 1
Start
IDLE
P
High Byte
MSB
0
S
P
Even Parity
Stop
1
LSB
0
MSB
1
Even Parity
Stop
0
Even Parity
Stop
Break
Start
Baud Command
S 1
Start
IDLE
MSB
LSB
Figure 13. Baud Rate Setup
IDLE
Read Write Baud Rate of
AS5261
AS5261 in Receiving
Mode
www.ams.com
Revision 1.1
18 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.3 OTP Programming Data
Table 12. OTP Memory Map
Data Byte
DATA15 (0x0F)
Bit Number
1
0
2
0
3
0
4
0
5
0
6
0
7
0
DATA11 (0x0B)
www.ams.com
0
0
2
0
3
0
4
0
5
0
6
0
7
0
0
0
1
0
2
CUSTID<0>
0
3
CUSTID<1>
0
4
CUSTID<2>
0
5
CUSTID<3>
0
6
CUSTID<4>
0
7
CUSTID<5>
0
0
CUSTID<6>
0
1
X2LIN<0>
0
2
X2LIN<1>
0
3
X2LIN<2>
0
4
X2LIN<3>
0
5
X1LIN<0>
0
6
X1LIN<1>
0
7
X1LIN<2>
0
0
X1LIN<3>
0
1
Y1LIN<0>
0
Revision 1.1
AMS (reserved)
Customer Identifier
Second linearization point (X-axis)
Customer Settings
DATA12 (0x0C)
Factory Settings
Description
Factory Settings
0
1
DATA13 (0x0D)
Default
0
0
DATA14 (0x0E)
Symbol
First linearization point (X-axis)
First linearization point (Y-axis)
19 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
Table 12. OTP Memory Map
Data Byte
DATA10 (0x0A)
DATA8 (0x08)
DATA7 (0x07)
www.ams.com
Symbol
Default
2
Y1LIN<1>
0
3
Y1LIN<2>
0
4
Y2LIN<0>
0
5
Y2LIN<1>
0
6
Y2LIN<2>
0
7
CLH<0>
0
0
CLH<1>
0
1
CLH<2>
0
2
CLH<3>
0
3
CLH<4>
0
4
CLH<5>
0
5
CLH<6>
0
6
CLH<7>
0
7
CLH<8>
0
0
CLL<0>
0
1
CLL<1>
0
2
CLL<2>
0
3
CLL<3>
0
4
CLL<4>
0
5
CLL<5>
0
6
CLL<6>
0
7
CLL<7>
0
0
CLL<8>
0
1
OFFSET<0>
0
2
OFFSET<1>
0
3
OFFSET<2>
0
4
OFFSET<3>
0
5
OFFSET<4>
0
6
OFFSET<5>
0
7
OFFSET<6>
0
0
OFFSET<7>
0
1
OFFSET<8>
0
2
OFFSET<9>
0
3
OFFSET<10>
0
4
OFFSET<11>
0
5
OFFSET<12>
0
6
OFFSET<13>
0
7
OFFSET<14>
0
Revision 1.1
Description
First linearization point (Y-axis)
Second linearization point (Y-axis)
Clamping Level High
Clamping Level Low
Customer Settings
DATA9 (0x09)
Bit Number
Offset
20 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
Table 12. OTP Memory Map
Data Byte
DATA6 (0x06)
DATA5 (0x05)
DATA3 (0x003)
Symbol
Default
0
OFFSET<15>
0
1
OFFSET<16>
0
2
OFFSET<17>
0
3
OFFSET<18>
0
4
OFFSET<19>
0
5
GAIN<0>
0
6
GAIN<1>
0
7
GAIN<2>
0
0
GAIN<3>
0
1
GAIN<4>
0
2
GAIN<5>
0
3
GAIN<6>
0
4
GAIN<7>
0
5
GAIN<8>
0
6
GAIN<9>
0
7
GAIN<10>
0
0
GAIN<11>
0
1
GAIN<12>
0
2
GAIN<13>
0
3
GAIN<14>
0
4
GAIN<15>
0
5
GAIN<16>
0
6
BP<0>
0
7
BP<1>
0
0
BP<2>
0
1
BP<3>
0
2
BP<4>
0
3
BP<5>
0
4
BP<6>
0
5
BP<7>
0
6
BP<8>
0
7
BP<9>
0
0
BP<10>
0
1
BP<11>
0
2
BP<12>
0
3
BP<13>
0
4
ANGLERNG
0
Sector selection
0=Angular Sector≥22.5 degrees;
1=Angular Sector<22.5 degrees
5
DIAG_HIGH
0
Failure Band Selection
0=Failure Band Low 1=Failure Band
High
DATA2 (0x02)
www.ams.com
Revision 1.1
Description
Offset
Scale Factor
Customer Settings
DATA4 (0x04)
Bit Number
Break Point
21 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
Table 12. OTP Memory Map
Data Byte
DATA2 (0x02)
DATA1 (0x01)
www.ams.com
Symbol
Default
Description
6
QUADEN<0>
0
7
QUADEN<1>
0
Quadrant Mode Enable
00=1quadrant;01=2quadrants;
10=3 quadrants;11=4 quadrants
0
AIRGAPSEL
0
1
HYSTSEL<0>
0
2
HYSTSEL<1>
0
3
FILTERCFG<0>
0
4
FILTERCFG<1>
0
5
Not used
0
6
Not used
0
7
Not used
0
0
RED_ADD<0>
0
1
RED_ADD<1>
0
2
RED_ADD<2>
0
3
RED_ADD<3>
0
4
RED_BIT<0>
0
5
RED_BIT<1>
0
6
RED_BIT<2>
0
Redundancy Bit
Identify the position of the bit to be
changed in the byte at the address
RED_ADD<3:0>
7
CUST_LOCK
0
Lock bit for Customer Area
Revision 1.1
Magnetic input range extension
0:extended range;1=normal range
Hysteresis selection
00=no hysteresis; 01: 56LSB;
10=91LSB; 11=137LSB
Filter Configuration
00=no filter; 01= fast;
10=moderate; 11=slow
Customer Settings
DATA0 (0x00)
Bit Number
Redundancy Address
Identify the address of the byte
containing the bit to be changed
22 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.4 READ / WRITE Register Map
Table 13. Read / Write Registers
Data Byte
DATA0 (0x20)
DATA2 (0x22)
www.ams.com
Symbol
Default
0
BAUDREG<0>
0
1
BAUDREG<1>
0
2
BAUDREG<2>
0
3
BAUDREG<3>
0
4
BAUDREG<4>
0
5
BAUDREG<5>
0
6
BAUDREG<6>
0
7
BAUDREG<7>
0
0
BAUDREG<8>
0
1
Not used
0
2
Not used
0
3
Not used
0
4
Not used
0
5
Not used
0
6
Not used
0
7
Not used
0
0
Not used
0
1
Not used
0
2
Not used
0
3
Not used
0
4
Not used
0
5
R1K10K<0>
0
6
R1K10K<1>
0
Selection of the reference resistance
used for OTP download
7
DSPRN
0
Resetn of the Digital Signal Processing
circuit
Revision 1.1
Description
UART Baud Rate Register
A read command returns all data bits
at 0
Read/Write Area
DATA1 (0x21)
Bit Number
23 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.5 READ Only Register Map
Table 14. Read Only Registers
Data Byte
Bit Number
Symbol
Default
Description
0
Not used
0
A read command returns 0
1
OFFSETFINISHED
0
Offset compensation finished
2
AGCFINISHED
0
AGC loop compensation finished
3
CORDICOVF
0
Overflow of the Cordic
4
AGCALARML
0
AGC loop saturation because of B field
too strong
5
AGCALARMH
0
AGC loop saturation because of B field
too weak
DATA0 (0x28)
DATA1 (0x29)
DATA3 (0x2B)
www.ams.com
OTP_RES
0
7
PARITY_ERR
0
UART parity error flag
0
CORDICOUT<0>
0
1
CORDICOUT<1>
0
2
CORDICOUT<2>
0
3
CORDICOUT<3>
0
4
CORDICOUT<4>
0
5
CORDICOUT<5>
0
6
CORDICOUT<6>
0
7
CORDICOUT<7>
0
0
CORDICOUT<8>
0
1
CORDICOUT<9>
0
2
CORDICOUT<10>
0
3
CORDICOUT<11>
0
4
CORDICOUT<12>
0
5
CORDICOUT<13>
0
6
Not used
0
7
Not used
0
0
DSPOUT<0>
0
1
DSPOUT<1>
0
2
DSPOUT<2>
0
3
DSPOUT<3>
0
4
DSPOUT<4>
0
5
DSPOUT<5>
0
6
DSPOUT<6>
0
7
DSPOUT<7>
0
Revision 1.1
Cordic Output
Read Area
DATA2 (0x2A)
6
0=1K resistance selected for OTP
download;
1=10K resistance selected for OTP
download
A read command returns all data bits
at 0
DSP Output
24 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
Table 14. Read Only Registers
Data Byte
DATA4 (0x2C)
DATA5 (0x2D)
DATA7 (0x2F)
www.ams.com
Symbol
Default
0
DSPOUT<8>
0
1
DSPOUT<9>
0
2
DSPOUT<10>
0
3
DSPOUT<11>
0
4
Not used
0
5
Not used
0
6
Not used
0
7
Not used
0
0
AGCVALUE<0>
0
1
AGCVALUE<1>
0
2
AGCVALUE<2>
0
3
AGCVALUE<3>
0
4
AGCVALUE<4>
0
5
AGCVALUE<5>
0
6
AGCVALUE<6>
0
7
AGCVALUE<7>
0
0
MAG<0>
0
1
MAG<1>
0
2
MAG<2>
0
3
MAG<3>
0
4
MAG<4>
0
5
MAG<5>
0
6
MAG<6>
0
7
MAG<7>
0
0
Not used
0
1
Not used
0
2
Not used
0
3
Not used
0
4
Not used
0
5
Not used
0
6
Not used
0
7
Not used
0
Revision 1.1
Description
DSP Output
A read command returns all data bits
at 0
AGC Value
Read Area
DATA6 (0x2E)
Bit Number
Magnitude of magnetic field
A read command returns all data bits
at 0
25 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.6 Special Registers
Table 15. Special Registers
Data Byte
DATA0 (0x41)
DATA1 (0x61)
www.ams.com
Default
0
AS5261KEY<0>
0
1
AS5261KEY<1>
0
2
AS5261KEY<2>
0
3
AS5261KEY<3>
0
4
AS5261KEY<4>
0
5
AS5261KEY<5>
0
6
AS5261KEY<6>
0
7
AS5261KEY<7>
0
0
AS5261KEY<8>
0
1
AS5261KEY<9>
0
2
AS5261KEY<10>
0
3
AS5261KEY<11>
0
4
AS5261KEY<12>
0
5
AS5261KEY<13>
0
6
AS5261KEY<14>
0
7
AS5261KEY<15>
0
0
AS5261KEY<0>
0
1
AS5261KEY<1>
0
2
AS5261KEY<2>
0
3
AS5261KEY<3>
0
4
AS5261KEY<4>
0
5
AS5261KEY<5>
0
6
AS5261KEY<6>
0
7
AS5261KEY<7>
0
0
AS5261KEY<8>
0
1
AS5261KEY<9>
0
2
AS5261KEY<10>
0
3
AS5261KEY<11>
0
4
AS5261KEY<12>
0
5
AS5261KEY<13>
0
6
AS5261KEY<14>
0
7
AS5261KEY<15>
0
Revision 1.1
Description
AS5261 KEY<15:0>=0101 0001 0110
0010
A write command with data different
from AS5261 KEY is not executed
A read command returns all data bits
at 0
AS5261 KEY<15:0>=0101 0001 0110
0010
A write command with data different
from AS5261 KEY is not executed
A read command returns all data bits
at 0
Pass2Func Register
DATA0 (0x60)
Symbol
Fuse Register
DATA1 (0x42)
Bit Number
26 - 32
AS5261
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
9.7 Programming Procedure
Pull-up on out pin
VDD=5V
Wait 10ms (after the startup time device enters communication mode)
Write command: Trimming bits are written in the OTP RAM
Read command: All the trimming bits are read back to check the correctness of the writing procedure.
Write
AS5261KEY in the Fuse register: The OTP RAM content is permanently transferred into the Poly Fuse cells.
Wait 10 ms (fuse time)
Write command,
R1K_10K<1:0>=(11)b: Poly Fuse cells are downloaded into the RAM memory using a 10K resistance as reference.
Wait 5 ms (download time)
Read R1K_10K register, the expected value is 00b
Write command,
R1K_10K<1:0>=(11)b
Read R1K_10K register, the expected value is (11)b. NB: Step11 and Step12 have to be consecutive.
Read command: all the fused bits downloaded with 10K resistance are read back.
Write command,
R1K_10K=<1:0>=(10)b: Poly Fuse cells are downloaded into the RAM memory using a 1K resistance as reference.
Wait 5 ms (download time)
Read R1K_10K register, the expected value is (00)b
Write command register,
R1K_10K<1:0>=(10)b
Read R1K_10K register, the expected value is (10)b NB: Step18 and Step19 have to be consecutive.
Read command: All the fused bits downloaded with 1K resistance are read back.
Check that read commands at Steps 5, 13 and 19 are matching
Write AS5261 KEY in the Pass2Func register:
www.ams.com
Device enters normal mode.
Revision 1.1
27 - 32
AS5261
Datasheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
10 Package Drawings and Markings
The device is available in a MLF-16 package.
Figure 14. Package Drawings and Dimensions
Symbol
A
A1
A2
A3
L
L1
L2
Θ
b
b1
D
E
e
D1
E1
D2
E2
aaa
bbb
ccc
ddd
eee
fff
N
Notes:
1.
2.
3.
4.
5.
Dimensions and tolerancing confirm to ASME Y14.5M-1994.
All dimensions are in miilimeters. Angles are in degrees.
Bilaretal coplanarity zone applies to the exposed pad as well as the terminal.
Radius on the terminal is optional.
N is the total number of terminals.
Min
0.80
0
0.50
0.05
0.05
0º
0.35
0.20
4.10
4.10
-
Nom
0.90
0.02
0.65
0.20 REF
0.60
0.15
0.10
0.40
0.25
6.00 BSC
6.00 BSC
1.00 BSC
5.75 BSC
5.75 BSC
4.20
4.20
0.15
0.10
0.10
0.05
0.08
0.10
16
Max
1.00
0.05
1.00
0.70
0.25
0.15
14º
0.45
0.30
4.30
4.30
-
Marking: YYWWIZZ.
www.ams.com
YY
WW
V
ZZ
Year
Week
Assembly plant identifier
Assembly traceability code
Revision 1.1
28 - 32
AS5261
Datasheet - P a c k a g e D r a w i n g s a n d M a r k i n g s
Figure 15. Vertical Cross Section of MLF-16
Notes:
1.
2.
3.
4.
All dimensions in mm.
Die thickness 0.150mm nom.
Adhesive thickness 0.011mm.
Spacer thickness 0.203mm typ.
www.ams.com
Revision 1.1
29 - 32
AS5261
Datasheet - R e v i s i o n H i s t o r y
Revision History
Revision
Date
1.0
30 Oct, 2012
1.1
31 Oct, 2012
Owner
mub
Description
Initial revision
Updated Figure 3, Table 1, Detailed Description and Added Section 9.1
Note: Typos may not be explicitly mentioned under revision history.
www.ams.com
Revision 1.1
30 - 32
AS5261
Datasheet - O r d e r i n g I n f o r m a t i o n
11 Ordering Information
The device is available as the standard products shown in Table 16.
Table 16. Ordering Information
Ordering Code
Description
12-bit
programmable
redundant
angle position sensor with PWM
AS5261-HMFP, -HMFM
outputs
Delivery Form
Package
Tape and Reel
MLF 16 6x6
Note: All products are RoHS compliant and ams green.
Buy our products or get free samples online at www.ams.com/ICdirect
Technical Support is available at www.ams.com/Technical-Support
For further information and requests, email us at sales@ams.com
(or) find your local distributor at www.ams.com/distributor
www.ams.com
Revision 1.1
31 - 32
AS5261
Datasheet - C o p y r i g h t s
Copyrights
Copyright © 1997-2012, ams AG, Tobelbaderstrasse 30, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered ®. All rights
reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the
copyright owner.
All products and companies mentioned are trademarks or registered trademarks of their respective companies.
Disclaimer
Devices sold by ams AG are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. ams AG makes no
warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described
devices from patent infringement. ams AG reserves the right to change specifications and prices at any time and without notice. Therefore, prior
to designing this product into a system, it is necessary to check with ams AG for current information. This product is intended for use in normal
commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability
applications, such as military, medical life-support or life-sustaining equipment are specifically not recommended without additional processing
by ams AG for each application. For shipments of less than 100 parts the manufacturing flow might show deviations from the standard
production flow, such as test flow or test location.
The information furnished here by ams AG is believed to be correct and accurate. However, ams AG shall not be liable to recipient or any third
party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or
indirect, special, incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the
technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of ams AG rendering of technical or other
services.
Contact Information
Headquarters
ams AG
Tobelbaderstrasse 30
A-8141 Unterpremstaetten, Austria
Tel
Fax
: +43 (0) 3136 500 0
: +43 (0) 3136 525 01
For Sales Offices, Distributors and Representatives, please visit:
http://www.ams.com/contact
www.ams.com
Revision 1.1
32 - 32