AMS AS5170 Series User manual

ams Datasheet Page 1
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AS5170
High-Resolution On-Axis Magnetic
Angular Position Sensor
The AS5170 is a high-resolution angular position sensor for
precise absolute angle measurement. The AS5170 is available
with an analog output interface (AS5170A and AS5170C) or a
digital output interface (AS5170B and AS5170D). The latter can
be programmed as a PWM or a SENT-compliant output
interface.
Based on a Hall sensor technology, this device measures the
orthogonal component of the flux density (Bz) over a full-turn
rotation and compensates for external stray magnetic fields
with a robust architecture based on a 14-bit sensor array and
analog front-end (AFE). A sub-range can be programmed to
achieve the best resolution for the application. To measure the
angle, only a simple two-pole magnet rotating over the center
of the package is required. The magnet may be placed above
or below the device. The absolute angle measurement provides
an instant indication of the magnet’s angular position. The
AS5170 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 AS5170A/B/C/D and a Magnet
Ordering Information and Content Guide appear at end of
datasheet.
General Description

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AS5170 − GeneralDescription
Key Benefits and Features
The benefits and features of this device are listed below:
Figure 2:
Added Value of Using AS5170
Applications
The AS5170 is ideal for applications like:
•Rotary button angle sensors
•Liquid-level measurement systems
•Contactless potentiometers
Benefits Features
•Resolve small angular excursion with high
accuracy •12-bit resolution @90° minimum arc
•Accurate angle measurement •Low output noise, low inherent INL
•Higher durability and lower system costs (no
shield needed) •Magnetic stray field immunity
•Enabler for safety critical applications •Functional safety, diagnostics, dual redundant chip
version

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AS5170 − General Description
Block Diagram
The functional blocks of the AS5170A, AS5170B, AS5170C and
AS5170D are shown below:
Figure 3:
Functional Blocks of the AS5170A and AS5170C
Figure 4:
Functional Blocks of the AS5170B and AS5170D
Analog
Front-End 14-bit A/D
Register Setting
OTP
UART
LDO
Reverse Polarity Protection
AS5170A
AS5170C
OUT
VDD
VDD3V3
GND
ATAN
(CORDIC) Digital Filter 12-bit D/A
AGC
Linearizator Driver
Hall Sensors
Analog
Front-end
AGC
14-bit A/D Driver
Register Setting
OTP
UART
LDO
Reverse Polarity Protection
OUT
VDD
VDD3V3
GND
PWM
Digital Filter
ATAN
(CORDIC)
SENT
Linearizator
Hall Sensors
AS5170B
AS5170D

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AS5170 − PinAssignments
Figure 5:
AS5170A/B/C/D Pin Assignment (Top View, SOIC8)
Figure 6:
AS5170A/B/C/D Pin Description
Pin Number Pin
Name Pin Type Description Comments
SOIC-8
1 VDD Supply Positive supply
2 TP1 n.a. Test pin Connected to ground
3 TP2 n.a. Test pin Leave open
4 TP3 n.a. Test pin Connected to ground
5OUT
Analog output (AS5170A
and AS5170C)
Digital output (AS5170B
and AS5170D)
Output
interface
AS5170A/C: analog output
AS5170B/D: PWM or SENT output
6 TP4 n.a. Test pin To be connected to OUT
7VDD
3V3 Supply
3.3V on-chip low-dropout (LDO)
output. Requires an external
decoupling capacitor (100nF).
8 GND Supply Ground
Pin Assignments
2
3
45
6
7
81
TP1
TP2
TP3
TP4
VDD
VDD3V3
GND
OUT
AS5170x

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AS5170 − Absolute Maximum Ratings
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. These are stress
ratings only. Functional operation of the device at these or any
other conditions beyond those indicated under Electrical
Characteristics is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect device
reliability.
Figure 7:
Absolute Maximum Ratings
Symbol Parameter Min Max Units Comments
Electrical Parameters
VDD DC Supply Voltage at
VDD pin -20 20 V Not operational
VOUT External DC voltage at
OUT pin -0.3 20 V Permanent
VDIFF DC voltage difference
between VDD and OUT -20 20
VREGOUT DC voltage at the
VDD3V3 pin -0.3 5.0 V
ISCR Input Current (latch-up
immunity) -100 100 mA Tests done according AEC Q100 004
Continuous Power Dissipation (TAMB = 70°C)
PTContinuous Power
Dissipation 300 mW
Electrostatic Discharge
ESDHBM Electrostatic Discharge
HBM ±2 kV Tests done according AEC Q100 002
Absolute Maximum Ratings

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AS5170 − AbsoluteMaximumRatings
Temperature Ranges and Storage Conditions
TAMB Operating Temperature
Range -40 150 °C Ambient temperature
TSTRG Storage Temperature
Range -55 125 °C 150°C for 1000h
TBODY Package Body
Temperature 260 °C
The reflow peak soldering temperature
(body temperature) is specified
according to 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)
RHNC Relative Humidity
(non-condensing) 585 %
MSL Moisture Sensitivity
Level 3 Represents a maximum floor life time of 168 hours
Symbol Parameter Min Max Units Comments

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AS5170 − Electrical Characteristics
All tolerances that are defined for external components in this
datasheet, are needed to be assured over the whole operation
conditions range and also over lifetime.
Overall condition: TAMB = -40°C to 150°C, VDD=4.5V to 5.5V;
Components spec; unless otherwise noted.
Figure 8:
Operating Conditions
Figure 9:
Electrical System Characteristics
Note(s):
1. Reference magnet: NdFeB, 8 mm diameter, 2.5 mm thickness
Symbol Parameter Conditions Min Typ Max Unit
VDD Positive supply voltage 4.5 5.0 5.5 V
VREG Regulated Voltage VDD3V3 should not be loaded by
any external DC current 3.3 3.45 3.6 V
IDD_A Supply current AS5170A/C AGC=255 (no magnet placed) 4 12 mA
lDD_B Supply current AS517B/D AGC=255 (no magnet placed) 4 10 mA
ISTART Supply current at start-up VREG = 2.25V 2.5 5 10 mA
TSUP Start-up time Functional mode 10 ms
Symbol Parameter Conditions Min Typ Max Unit
CRES Core resolution 14 bit
ARES Analog resolution
(AS5170A/C) Range > 90° 12 bit
DRES Digital resolution
(AS5170B/D) 12 bit
INLopt Integral non-linearity
(optimum)
Best aligned reference magnet
(1)
at 25°C over full turn 360° -0.5 0.5 deg
INLtemp Integral non-linearity
(optimum)
Best aligned reference magnet
(1)
over temperature -40ºC to 150°C
over full turn 360°
-0.9 0.9 deg
INL Integral non-linearity
Best aligned reference magnet
(1)
over temperature -40Cº to150ºC
over full turn 360º and
displacement
-1.4 1.4 deg
ON Output noise peak to peak Static conditions - filter on 1 LSB
ST Sampling time 125 μs
Electrical Characteristics

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AS5170 − ElectricalCharacteristics
Figure 10:
Power Management - Supply Monitor - Timing
Symbol Parameter Conditions Min Typ Max Unit
VDDUVTH VDD undervoltage upper
threshold 3.5 4.0 4.5 V
VDDUVTL VDD undervoltage lower
threshold 3.0 3.5 4.0 V
VDDUH VDD undervoltage
hysteresis 300 500 900 mV
UVDT VDD undervoltage
detection time
Time devices detects
undervoltage
VDD< VDDUVTH
10 50 250 μs
UVRT Undervoltage recovery time
Time device return into
normal mode from failure
band VDD > VDDUVTH
10 50 250 μs
VDDOVTH VDD overvoltage upper
threshold 6.0 6.5 7.0 V
VDDOVTL VDD overvoltage lower
threshold 5.5 6.0 6.5 V
VDDOH VDD overvoltage hysteresis 300 500 900 V
OVDT VDD overvoltage detection
time
Time devices detects
overvoltage
VDD> VDDOVTL
500 1000 2000 μs
OVRT VDD overvoltage recovery
time
Time device return into
normal mode from failure
band VDD < VDDOVTL
500 1000 2000 μs
TDETWD WatchDog error detection
time
Time device detects
oscillator failure till output
is in failure band
12 ms

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AS5170 − Electrical Characteristics
TAMB = -40°C to 150°C, VDD = 4.5V to 5.5V, unless otherwise
noted.
Two-pole cylindrical diametrically magnetized source:
Figure 11:
Magnetic Characteristics
Note(s):
1. Reference magnet: NdFeB, 6 mm diameter, 2.5 mm thickness
Figure 12:
Electrical and Timing Characteristics Analog Output (AS5170A/C)
Symbol Parameter Conditions Min Typ Max Unit
Bz Orthogonal magnetic
field strength
Required orthogonal component of
the magnetic field strength
measured at the package surface
along a circle of 1.25 mm
MFER = 0
30 70 mT
BzE
Orthogonal magnetic
field strength
–Extended mode
Required orthogonal component of
the magnetic field strength
measured at the package surface
along a circle of 1.25mm
MFER = 1
10 90 mT
Disp(1) Displacement radius
Offset between defined device
center and magnet axis. Dependent
on the selected magnet.
0.5 mm
Symbol Parameter Conditions Min Typ Max Unit
INLOS INL output stage -6 +6 LSB
DNLOS DNL output stage -5 +5 LSB
RERR Ratiometricity error -0.5% 0.5% VDD
BVPU
Output voltage
broken VDD with
pull-up resistor
Pull-up resistor must be in the
specified range (see Figure 31)96 100 %VDD
BGPD
Output voltage
broken ground with
pull-down resistor
Pull-down resistor must be in the
specified range (see Figure 31)04%VDD
OSSCG Output short-circuit
current GND OUT = GND 5 10 20 mA
OSSCV Output short-circuit
current VDD OUT = VDD -20 -10 -5 mA
OSSDT Output short-circuit
detection time OUT = GND or OUT = VDD 20 200 600 μs

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AS5170 − ElectricalCharacteristics
Note(s):
1. For each code the ratiometricity error is defined as follows:
VOUTRATE=((VOUTact – (VOUTtyp*(VDDact/ VDDtyp)))/VDDtyp)*100
Where
- VOUTact is the actual output voltage
- VOUTtyp is the typical output voltage
- VDDact is the actual supply voltage
- VDDtyp is the typical supply voltage
Figure 13:
Electrical and Timing Characteristics PWM Output (AS5170B/D)
OSSRT Output short-circuit
recovery time 2520ms
OLCH Output level
clamping high Output current at OUT pin -3 mA 96 %VDD
OLCL Output level
clamping low Output current at OUT pin 3 mA 4 %VDD
OSPSR
Output stage positive
step response (driver
only)
From 0 to 90%VDD, measured at
OUT pin, with RPUOUT = 4.7kΩ,
CLOAD = 1nF, VDD = 5V
250 μs
OSNSR
Output stage
negative step
response (driver only)
From VDD to 10%VDD, measured at
OUT pin, with RPUOUT = 4.7kΩ,
CLOAD = 1nF, VDD = 5V
250 μs
OSTD Output stage
temperature drift
Of value at mid code, info parameter
not tested in production -0.2 0.2 %
Symbol Parameter Conditions Min Typ Max Unit
PWMSSOCG Short-circuit output
current OUT = GND 5 10 20 mA
PWMSSOCV Short-circuit output
current OUT = VDD -20 -10 -5 mA
PWMSSDT PWM short-circuit
detection time OUT = GND or OUT = VDD 5
PWM
clock
cycles
PWMSSRT PWM short circuit
recovery time 6
PWM
clock
cycles
BKPWMVOH
PWM output voltage
high in broken
condition
Broken VDD or broken GND,
OUT = high, RPU = 10kΩ,
PWMVOH=VDD-VOUT
00.4V
BKPWMVOL PWM output voltage
low in broken condition
Broken VDD or broken GND,
OUT = low, RPD = 10kΩ 00.4V
PWMF7 PWM frequency PWMFR = 111 112.5 125 137.5 Hz
Symbol Parameter Conditions Min Typ Max Unit

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AS5170 − Electrical Characteristics
PWMF6 PWM frequency PWMFR = 110 180 200 220 Hz
PWMF5 PWM frequency PWMFR = 101 225 250 275 Hz
PWMF4 PWM frequency PWMFR = 100 360 400 440 Hz
PWMF3 PWM frequency PWMFR = 011 450 500 550 Hz
PWMF2 PWM frequency PWMFR = 010 720 800 880 Hz
PWMF1 PWM frequency PWMFR = 001 900 100 1100 Hz
PWMF0 PWM frequency PWMFR = 000 1800 2000 2200 Hz
PWMVOH PWM output voltage
level high
IOUT = 5 mA,
PWMVOH = VDD - VOUT 00.4V
PWMVOL PWM output voltage
level low IOUT = 5 mA 0 0.4 V
PWMSRF PMM slew rate fast
Between 25% and 75% of
VDD, RPUOUT = 4.7kΩ,
CLOUT1 = 1nF, PWMSR = 0
124V/μs
PWMSRS PMM slew rate slow
Between 25% and 75% of
VDD, RPUOUT = 4.7kΩ,
CLOUT1 = 1nF, PWMSR = 1
0.5 1 2 V/μs
Symbol Parameter Conditions Min Typ Max Unit

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AS5170 − ElectricalCharacteristics
Timing Characteristics
Figure 14:
Electrical and Timing Characteristics SENT Output (AS5170B/D)
Figure 15:
Electrical and Timing Characteristics UART Interface
Symbol Parameter Conditions Min Typ Max Unit
SENTSSOC SENT short-circuit output
current OUT = 20V 10 20 40 mA
SENTSSOC SENT short-circuit output
current OUT = 0V -40 -20 -10 mA
BKSENTVOH SENT output voltage in
broken condition
Broken VDD or broken GND,
RPU = 50kΩ, SENT
constantly high
01.2V
SENTVOH SENT output voltage
high 4.1
SENTVOL SENT output voltage low 0.5 V
SENTFT SENT fall time 6.5 μs
SENTRT SENT rise time 18 μs
Symbol Parameter Conditions Min Typ Max Unit
UARTVIH UART high level input voltage 70 %VDD
UARTVIL UART low level input voltage 30 %VDD
UARTVOH UART high level output voltage VDD - 0.5V %VDD
UARTVOL UART low level output voltage 0.5 %VDD
UARTBRLIM UART Baud rate 2400 9600 Baud

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AS5170 − Detailed Description
The AS5170 is a Hall-based rotary magnetic position sensor
using a CMOS technology. The lateral Hall sensor array converts
the magnetic field component perpendicular to the surface of
the chip into a voltage.
The signals coming from the Hall sensors are first amplified and
filtered before being converted by the analog-to-digital
converter (ADC). The output of the ADC is processed by the
CORDIC block (Coordinate-Rotation Digital Computer) to
compute the angle and magnitude of the magnetic field vector.
The sensor and analog front-end (AFE) section works in a closed
loop alongside an AGC to compensate for temperature and
magnetic field variations. The calculated magnetic field
strength (MAG), the automatic gain control (AGC) and the angle
can be read through the output pin (OUT) in UART mode.
The magnetic field coordinates provided by the CORDIC block
are fed to a digital filter which reduces noise. A linearization
block generates the transfer function, including linearization.
The AS5170 is available with three different output interfaces:
analog ratiometric (AS5170A/C), digital PWM or SENT
(AS5170B/D).
The output of the AS5170 can be programmed to define a
starting position (zero angle) and a stop position (maximum
angle). An embedded linearization algorithm allows reducing
the system INL error due, for example, to mechanical
misalignment, magnet imperfections, etc.
The AS5170 can be programmed through the OUT pin with a
UART interface which allows writing an on-chip non-volatile
memory (OTP) where the specific settings are stored. The
AS5170 can be programmed by the ams programming tool,
both at the component and board level.
Detailed Description

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AS5170 − RegisterDescription
Figure 16:
Non-Volatile Memory Register Description
Address Bit
Position Field Description
0x0A 7:0 CUSTID0 Customer ID byte 0
0x0B 7:0 CUSTID1 Customer ID byte 1
0x0C 7:0 CUSTID2 Customer ID byte 2
0x0D 7:0 CUSTID3 Customer ID byte 3
0x0E
0PWMINV PWM inverted
1PWMSR
PWM slew rate
(0 = PWM slew rate fast PWMSRF,
1 = PWM slew rate slow PWMSRS)
3:2 DIGOS
Digital output stage
(00 = PWM push-pull
01 = PWM pull-down
10 = PWM pull-up
11 = SENT)
Only applicable to AS5170B and AS5170D
6:4 RBKDEB Read-back debouncing
7n.a Nouse
0x0F
0FBS Failure band selection (0 = lower failure band, 1 = upper
failure band)
2:1 HYST Hysteresis across the brake point
4:3 QUAD Quadrant selection
7:5 PWMFR PWM frequency selection
0x10
1:0 PWMRTH PWM rising threshold tbd
3:2 PWMFTH PWM falling threshold tbd
7:4 SENTMID SENT Message ID
0x11
4:0 SENTTK SENT tick
5SENTESM Enable SENT serial message
6SENTPP SENT pause pulse enable (0 = disable, 1 = enable)
7SENTRC SENT rolling counter enable (0 = disable, 1 = enable)
0x12
3:0 n.a No use. Default 0
7:4 n.a No use. Default 0
Register Description

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AS5170 − Register Description
0x13
3:0 n.a No use. Default 0
7:4 n.a No use. Default 0
0x14 7:0
CLMPH
Clamping level high
Reg 0x14[0] =LSB
Reg 0x15[3]=MSN
0x15
3:0
7:4
CLMPL
Clamping level low
Reg 0x15[4] =LSB
Reg 0x16[7]=MSN
0x16 7:0
0x17 7:0
PPOFFSET
Post processing offset
Reg 0x17[0] =LSB
Reg 0x19[3]=MSB
0x18 7:0
0x19
3:0
7:4
PPGAIN
Post processing gain
Reg 0x19[4] =LSB
Reg 0x1B[3]=MSB
0x1A 7:0
0x1B
4:0
7:5
BP
Break point
Reg 0x1B[5] =LSB
Reg 0x1D[2]=MSB
0x1C 7:0
0x1D
2:0
3MFER Magnetic field extended range (1 = Bz, 0= BzE)
4AER Angle extended range (set to 1 if the maximum angle
excursion is smaller than 22 degree)
6:5 FILTER Post processing filter
7 CUSLOCK Customer settings lock
0x1E 7:0 SIGN Signature for error correction code
Address Bit
Position Field Description

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AS5170 − RegisterDescription
Figure 17:
Volatile Memory Register Description
Figure 18:
Special Functions
Address Bit
Position Field R/W Description
0x22 7:0
DAC12IN
R/W Input word of the 12-bit output DAC
(Reg0x23[3] = MSB, Reg0x22[0] = LSB)
0x23
3:0 R/W
4 DAC12INSEL R/W DAC 12 input buffer selection
5 DSPRN R/W Digital signal processing reset
6 GLOAD R/W Enable of gload
7--Notused
0x32 7:0
ANGLECORDIC R Angle of the CORDIC output block.
(Reg0x33[5] = MSB, Reg0x32[0] = LSB)
0x33
5:0
7:6 - - Not used
0x34 7:0 MAG R CORDIC magnitude
0x35 7:0 AGC R AGC value
0x36 7:0
ANGLEFILTER R Angle of the digital filter output block
(Reg0x37[3] = MSB, Reg0x36[0] = LSB)
0x37 3:0
0x37 7:4 - - Not used
Address Bit Position Field Description
0x60 7:0
P2F Pass-to-functions, see UART
0x61 7:0
0x62 7:0
BURNOTP Permanently burn OTP, see UART
0x63 7:0

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AS5170 − Register Description
UART Interface
The AS5170 is equipped with a UART interface, which allows
reading and writing the registers as well as permanently
programming the non-volatile memory (OTP). By default
(factory setting) the AS5170 is in the so-called Communication
Mode and the UART is connected at the output pin (OUT). In this
mode, it is possible to configure the register settings. In this
mode, the device is in open-drain mode and therefore a pull-up
resistor has to be connected on the output.
The UART interface allows reading and writing two consecutive
addresses. The standard UART sequence consists of four frames.
Each frame begins with a start bit (START), which is followed by
8 data bits (D[0:7]), one parity bit (PAR), and a stop bit (STOP),
as shown in Figure 19.
Figure 19:
UART Frame
The PAR bit is even parity calculated over the data bits (D[0:7]).
Each frame is transferred from LSB to MSB.
The four frames are shown in Figure 20.
Figure 20:
UART Frame Sequence
The first frame is the synchronization frame and consists of
D[0:7] = 0x55 followed by the parity bit (PAR=0) and the stop
bit. This frame synchronizes the baud rate between the AS5170
and the host microcontroller.
The second frame contains the read/write command (D[7] = 0
Write, D[7] = 1 Read) and the address of the register (D[6:0] =
ADDRESS).
The content of the third and fourth frames (DATA1 and DATA2)
will be written to or read from the location specified by
ADDRESS and ADDRESS+1, respectively.
Frame Number D[7] D[6] D[5] D[4] D[3] D[2] D[1] D[0]
10x55
2R/W ADDRESS
3DATA1
4DATA2
STARTD[0]D[1]D[2]D[3]D[4]D[5]D[6]D[7]PARSTOP

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AS5170 − RegisterDescription
Figure 21 and Figure 22 show examples of read and write.
Figure 21:
Example of Write (Reg[0x22] = 0x18, Reg[0x23] = 0xA2)
Figure 22:
Example of Read (Reg[0x2B], Reg[0x2C])
Exiting Communication Mode
Communication mode is exited and operational mode is
entered with a Pass-to-function (P2F) command, by writing to
the virtual registers 0x60 and 0x61:
P2F: write(0x60) = 0x70, write(0x61) = 0x51
No more commands can be sent after sending this command,
because the device is permanently placed in operational mode.
Burning the OTP Registers
The BURNOTP command writes the OTP registers with their
programmed values. The command is issued by writing to
virtual registers 0x62 and 0x63:
BURNOTP: write(0x62) = 0x70, write(0x63) = 0x51
Customer ID
A specific identifier chosen by the user can be stored in the
non-volatile memory. This identifier consists of 4 bytes and can
be stored in the locations CUSTID0, CUSTID1, CUSTID2, and
CUSTID3.
1100110000100010
START
PAR
STOP
0x55
START
00011
PAR
STOP
START
0x22
00101000 00 01000100111
PAR
STOP
START
PAR
STOP
0x18 0xA2
WRITE
01
LSB
MSB
LSB
MSB
LSB
MSB
LSB
MSB
1100110010111
1
0
0
START
PAR
STOP
0x55
START
1
0011
PAR
STOP
START
0x2B
0 01
PAR
STOP
START
Content of
register 0x2B
READ
1
PAR
STOP
Content of
register 0x2C
LSB
MSB
0
MSB
LSB
LSB
MSB
LSB
MSB

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AS5170 − Register Description
Output Linear Transfer Function
A linear transfer function controls the state of the output in
response to the absolute orientation of the external magnet.
The parameters which control this function are shown in
Figure 24.
Figure 23:
Transfer Function Control Parameters
As shown in the Figure 24, the parameters T1, T2, OT1, and OT2
define the input-to-output linear transfer function. The
dedicated programmer for the AS5170 uses the parameters
from Figure 23 to generate the corresponding settings CLMPL,
CLMPHH, PPOFFSET, PPGAIN and BP (see Figure 24).
The clamping level parameters CLMPL and CLMPH define the
absolute minimum and maximum level of the output. Both
clamping levels can be set with the 9 LSBs out of the 12-bit
output resolution. This means that the maximum value for
CLMPL is one eighth, while CLMPH minimum value is
seven-eighths of the output diagnostic. CLMPL and CLMPH
must always be set outside of the lower and upper diagnostic
failure band defined by the output broken wire voltage (see
Figure 24: BGPD and BVPU).
Symbol Parameter Resolution [bit]
T1 Mechanical angle starting point 14
T2 Mechanical angle stop point 14
OT1 Output at the starting point (T1) 12
OT2 Output at the stop point (T2) 12
CLMPL Clamping level low 12
CLMPH Clamping level high 12
BP Breakpoint 14

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AS5170 − RegisterDescription
Figure 24:
Output Transfer Function
The breakpoint BP sets the discontinuity point where the
output jumps from one clamping level to the other. It is strongly
recommended to set the breakpoint at the maximum distance
from the start and stop position (T1 and T2). To handle the case
of a full turn, a hysteresis function across the breakpoint can be
used to avoid sudden jumps between the lower and upper
clamping level.
Figure 25:
Hysteresis Setting
HYST Hysteresis LSBs
00 0
01 56
10 91
11 137
Upper failure band
Lower failure band
Max out
CLMPH
CLMPL
OT2
OT1
T1 T2
BGPD
BVPU
Upper clamping band
Lower clamping band
BP
Electrical range
Mechanical range
Mechanical angle
Measured angle