Datasheet AS5134 Datasheet (AUSTRIA MICRO SYSTEMS)

AS5134

360 Step Programmable High Speed Magnetic
Rotary Encoder

Data Sheet

1 General Description

The AS5134 is a contactless magnetic rotary encoder
for accurate angular measurement over a full turn of
360º.

It is a system-on-chip, combining integrated Hall
elements, analog front-end and digital signal processing
in a single device.

To measure the angle, only a simple two-pole magnet,
rotating over the center of the chip is required.

The absolute angle measurement provides instant
indication of the magnet’s angular position with a
resolution of 8.5 bit = 360 positions per revolution. This
digital data is available as a serial bit stream and as a
PWM signal.

In addition to the angle information, the strength of the
magnetic field is also available as a 6-bit code.

Data transmission can be configured for 1-wire (PWM),
2-wires (DCLK, DIO) or 3-wires (DCLK, DIO, CS).

A software programmable (OTP) zero position simplifies
assembly as the zero position of the magnet does not
need to be mechanically aligned.

A Power Down Mode together with fast startup and
measurement cycles allows for very low average power
consumption.

2 Key Features

 360º contactless angular position encoding

 Two digital 360 step (8.5 bit) absolute outputs: Serial

interface and Pulse width modulated (PWM) output

 User programmable zero position and sensitivity

 High speed: upto 25.000 rpm

 Direct measurement of magnetic field strength

allows exact determination of vertical magnet dis­tance

 Incremental Outputs ABI Quadrature: 90 ppr, step

direction: 180ppr, fixed pulse width 360ppr

 BLDC Outputs UVW, selectable for 1,2,3,4,5,6 pole

pairs

 Daisy-Chain mode for cascading of multiple sensors

 9-bit multiturn counter

 Low power mode with fast startup

 Wide magnetic field input range: 20 – 80 mT

 Wide temperature range: -40ºC to +140ºC

 Fully automotive qualified to AEC-Q100

 Small Pb-free package: SSOP 20

3 Applications

Figure 1. Block Diagram

VDD5V

GND

Hall Array

&
Frontend
Amplifier

power management

V

U

W

Commutation

Interface

tracking

ADC &

Angle

decoder

AS5134

The AS5134 is suitable for contactless rotary position
sensing, rotary switches (human machine interface),
AC/DC motor position control and Brushless DC motor
position control.

A

B Index

Incremental

Interface

PWM

Decoder

PWM

Multiturn

Angle

Counter

Absolute

Serial

Interface

(SSI)

DIO

CS
CLK

C2

DX

PROG

Zero
Pos.

Mag

AGC

AGC

OTP

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AS5134

Data Sheet - App licat io ns

Contents

1 General Description.............................................................................................................................. 1

2 Key Features ........................................................................................................................................ 1

3 Applications .......................................................................................................................................... 1

4 Pin Assignments................................................................................................................................... 4

Pin Descriptions ................................................................................................................................................... 4

5 Absolute Maximum Ratings.................................................................................................................. 5

6 Electrical Characteristics ...................................................................................................................... 6

Timing Characteristics.......................................................................................................................................... 8

7 Detailed Description ............................................................................................................................. 9

Connecting the AS5134 ....................................................................................................................................... 9

Serial 3-Wire R/W Connection............................................................................................................................ 10

Serial 3-Wire Read-only Connection.............................................................................................................. 11

Serial 2-Wire Connection (R/W Mode) ............................................................................................................... 12

Serial 2-Wire Differential SSI Connection ...................................................................................................... 12

1-Wire PWM Connection................................................................................................................................ 13

Analog Output ................................................................................................................................................ 14

Quadrature A/B/Index Output......................................................................................................................... 15

Brushless DC Motor Commutation Mode....................................................................................................... 15

Daisy Chain Mode.......................................................................................................................................... 16

Serial Synchronous Interface (SSI) .................................................................................................................... 19

AS5134 Programming ........................................................................................................................................ 20

OTP Programming Connection ...................................................................................................................... 20

Programming Verification............................................................................................................................... 21

AS5134 Status Indicators ................................................................................................................................... 22

Lock Status Bit ............................................................................................................................................... 22

Magnetic Field Strength Indicators................................................................................................................. 22

Multi Turn Counter.............................................................................................................................................. 23

High Speed Operation........................................................................................................................................ 23

Propagation Delay.......................................................................................................................................... 24

ADC Sampling Rate ....................................................................................................................................... 24

Chip Internal Lowpass Filtering...................................................................................................................... 24

Digital Readout Rate ...................................................................................................................................... 24

Total Propagation Delay of the AS5134 ......................................................................................................... 24

Low Power Mode ........................................................................................................................................... 25

Magnet Diameter and Vertical Distance ..........................................................................................

The Linear Range .......................................................................................................................................... 26

Magnet Thickness .......................................................................................................................................... 28

Axial Distance (Airgap)................................................................................................................................... 29

Angle Error vs. Radial and Axial Misalignment .............................................................................................. 29

Accuracy ........................................................................................................................................................ 29

Mounting the Magnet ..................................................................................................................................... 30

Summary........................................................................................................................................................ 32

8 Application Information ....................................................................................................................... 33

Benefits of AS5134............................................................................................................................................ 33

AS5134 Parameter and Features List ................................................................................................................ 33

................... 26

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AS5134

Data Sheet - App licat io ns

9 Package Drawings and Markings ....................................................................................................... 36

Recommended PCB Footprint ........................................................................................................................... 37

10 Ordering Information......................................................................................................................... 38

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AS5134

Data Sheet - Pin A ssi gn men ts

4 Pin Assignments

Figure 2. Pin Assignments (Top View)

Prog

VSS

DX

CS

C2

PWM

VDD

Te st C oi l

DCLK

DIO

1

2

3

4

5

6

7

8

9

10

20

19

18

17

16

15

AS5134

14

13

12

11

Pin Descriptions

Table 1. Pin Descriptions

Pin Name Pin Number Description

Prog 1

VSS 2

DX 3

CS 4

C2 5

PWM 6

VDD 7

Test Coil 8

DDCLK 9

DIO 10

U11

V12

W13

A14

B15

Index 16

TB0 17

TB1 18

TB2 19

TB3 20

Programming voltage input, must be left open in normal operation.
Maximum load = 20pF (except during programming)

Supply ground

Chip select output for 2-wire mode and Daisy Chain cascading

Chip select input for 3-wire mode

Select between 2-wire (C2 → VDD) and 3-wire (C2 → VSS) mode

PWM output

Positive supply voltage (double bond to VDD_A and VDD_D)

Test pin

Clock input for serial interface

Data I/O for serial interface

Commutation output

Commutation output

Commutation output

Incremental output

Incremental output

Incremental output

Test pin

Test pin

Test pin

Test pin

TB3

TB2

TB1

TB0

Index

B

A

W

V

U

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AS5134

Data Sheet - Abs olute M axi mu m R at ing s

5 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

Parameter Min Max Units Comments

Supply voltage -0.3 7 V Except during OTP programming

Input Pin Voltage VSS-0.5 VDD V

Input Current (latch up immunity) -100 100 mA Norm: EIA/JESD78 ClassII Level A

ESD ±2 kV Norm: JESD22-A114E

Package Thermal Resistance SL 145 ºC/W Still Air / Single Layer

Package Thermal Resistance ML 90 ºC/W Still Air / Multi Layer

Storage Temperature -55 140 ºC

Soldering conditions, Body temperature

(Pb-free package)

Humidity non-condensing 5 85 %

260 ºC

T=20 to 40s, Norm: IPC/JEDEC J-Std-020C.

Lead finish 100%Sn “matte tin”

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AS5134

Data Sheet - Ele ct ric al Ch ar act er istic s

6 Electrical Characteristics

TAMB = -40 to 140ºC, VDD5V = 4.5-5.5V, all voltages referenced to VSS, unless otherwise noted.

Table 3. Electrical Characteristics

Symbol Parameter Conditions Min Typ Max Units

V

DD

I

DD

I

off

T

J

Positive Supply Voltage

Operating Current

Power down current

Junction Temperature

System Parameters

Resolution

Power Up Time

Tracking rate

Accuracy

Propagation delay

Transition noise

T

PwrUp

INL

t

delay

TN

N

t

s

cm

Magnet Specifications

MD

MT

B

V

i

i

Magnet diameter

Magnet thickness

Magnetic Input Range

Magnet rotation speed

Hall Array radius

Vertical distance of magnet

Horizontal magnet displacement

radius

PWM Output

N

PW

PW

t

f

PWM

MIN

MAX

PWM

PWM

PWM resolution

PWM pulse width

PWM pulse width

PWM period

PWM frequency

Programming Parameters

V

PROG

I

PROG

Programming Voltage

Programming Current

No load on outputs. Supply

current can be reduced by using

stronger magnets.

Low Power Mode 70 120 µA

Startup from zero ≤4100

Startup from Low Power mode ≤500

Step rate of tracking ADC;

1 step = 1º

Centered Magnet -2 2 Deg

Within horizontal displacement

radius (4.4)

Peak-Peak 1.41 Deg

Diametrically magnetized 6 mm

Package surface 20 80 mT

to maintain locked state 25.000 rpm

Max X-Y Offset between

defined IC Package center and

magnet axis

Max X-Y Offset between chip

center and magnet axis

1 Step = 1º 2 µs/step

Angle = 0º (00

Angle = 360º (FF

)

H

)

H

=1 / PWM period 1.33 kHz

Static voltage at pin Prog 8.0 8.5 V

4.5 +5.5 V

15 mA

170 ºC

8.5 Bit

1Deg

3.0 4 5.2 µs/step

-3 3 Deg

17 22 µs

2.5 mm

1mm

0.5 1 1.8 mm

0.25

0.48

8.5 Bit

16 µs

734 µs

750 µs

100 mA

µs

mm

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AS5134

Data Sheet - Ele ct ric al Ch ar act er istic s

Table 3. Electrical Characteristics (Continued)

Symbol Parameter Conditions Min Typ Max Units

Ta mb

t

PROG

V

V

R,unprog

PROG

R,prog

Programming ambient

temperature

Programming time

Analog readback voltage

During programming 0 85 ºC

Timing is internally generated 2 4 µs

During analog readback mode

at pin Prog

0.5

2.2 3.5

Hall Element Sensitivity Options

sens

Hall Element sensitivity setting

sens = 00 (default;

high sensitivity)

sens = 01 1.88

1.65

sens = 10 2.11

sens = 11 (low sensitivity) 2.35

DC Characteristics of Digital Inputs and Outputs

CMOS Inputs: DDCLK, CS, DIO, C2

IH

V

VIL

ILEAK

High level input voltage

Low level input voltage

Input leakage current

0.7*VDD V

0.3*V

DD V

1µA

CMOS Outputs: DIO, PWM, DX

VOH

V

OL

CL

High level output voltage

Low level output voltage

Capacitive load

Source current < 4mA V

DD-0.5 V

Sink current < 4mA VSS+0.4 V

35 pF

CMOS Tristate Output: DIO

IO

Z

Tristate leakage current

CS = low 1 µA

V

X

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AS5134

Data Sheet - Ele ct ric al Ch ar act er istic s

Timing Characteristics

Table 4. Timing Characteristics

Symbol Parameter Conditions Min Typ Max Units

2-/3-Wire Data Transmission

3-Wire Interface

f

DCLK

f

DCLK,P

f

DCLK

f

DCLK,P

General Data Transmission

t0 Rising DCLK to CS 15 - ns

t1

t2 Chip select to drive bus externally - - ns

t3

t4

t5

t6

t7

t8

t9

t10

t

TO

Clock Frequency Normal operation No limit 5 6 MHz

Clock Frequency During OTP programming 200 650 kHz

2-Wire Interface

Clock Frequency Normal operation 0.1 5 6 MHz

Clock Frequency During OTP programming 200 500 kHz

Chip select to positive edge of

DCLK

15 - ns

Setup time command bit,

Data valid to positive edge of

30 - ns

DCLK

Hold time command bit,

Data valid after positive edge of

30 ns

DCLK

Float time,

Positive edge of DCLK for last

30 DCLK/2 ns

command bit to bus float

Bus driving time,

Positive edge of DCLK for last

command bit to bus drive

Setup time data bit,

Data valid to positive edge of

DCLK

Hold time data bit,

Data valid after positive edge of

DCLK

DCLK/2

+0

DCLK/2

+0

DCLK/2

+0

Hold time chip select,

Positive edge DCLK to negative

30 ns

edge of chip select

Bus floating time,

Negative edge of chip select to

030ns

float bus

Timeout period in 2-wire mode

(from rising edge of DCLK)

20 24 µs

DCLK/2

+30

DCLK/2

+30

DCLK/2

+30

ns

ns

ns

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AS5134

Data Sheet - Det ai led D es cri pt ion

7 Detailed Description

Figure 3. Typical Arrangement of AS5134 and Magnet

Connecting the AS5134

The AS5134 can be connected to an external controller in several ways as listed below:

 Serial 3-wire R/W connection

 Serial 3-wire Read-only connection

 Serial 2-Wire connection (R/W Mode)

 Serial 2-Wire Differential SSI connection

 1-Wire PWM connection

 Analog output

 Quadrature A/B/Index output

 Brushless DC Motor Commutation Mode

 Daisy Chain Mode

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AS5134

Data Sheet - Det ai led D es cri pt ion

Serial 3-Wire R/W Connection

In this mode, the AS5134 is connected to the external controller via three signals: Chip Select (CS), Clock (DCLK)
inputs and bi-directional DIO (Data In/Out) output. The controller sends commands over the DIO pin at the beginning of
each data transmission sequence, such as reading the angle or putting the AS5134 in and out of the reduced power
modes.

Figure 4. SSI Read/Write Serial Data Transmission

+5V

VDD

CS

DCLK

DIO

VDD

AS5134

C2

100n

VSS

VDD

Output

Output

I/O

Micro Controller

VSS

VSS

A pull-down resistor (as shown in Figure 5) is not required. C2 is a hardware configuration input. C2 selects 3-wire
mode (C2 = low) or 2-wire mode (C2 = high).

command phase data phase

t

CLK

DCLK

CS

DIO

DIO

1

t1

t3

t4

CMD3

2

3

4

5672120

t5

CMD0CMD4

t7

t6

t8

D15 D14 D1

D0

t9

DIO read

t10

DIO write

Table 5. Serial Bit Sequence (16bit read/write)

Write Command Read/Write Data

C4 C3 C2 C1 C0 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

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AS5134

Data Sheet - Det ai led D es cri pt ion

Serial 3-Wire Read-only Connection

This simplified connection is possible when the AS5134 is only used to provide the angular data (no power down or
OTP access). The Chip Select (CS) and Clock (DCLK) connection is the same as in the R/W mode, but only a digital
input pin (not an I/O pin) is required for the DIO connection. As the first 5 bits of the data transmission are command
bits sent to the AS5134, both the microcontroller and the AS5134 are configured as digital inputs during this phase.
Therefore, a pull-down resistor must be added to make sure that the AS5134 reads “00000” as the first 5 bits, which
sets the Read_Angle command.

Note: All further application examples are shown in R/W mode, however read-only mode is also possible unless

otherwise noted.

Figure 5. SSI Read-only Serial Data Transmission

+5V

VDD

DCLK

CS

DIO

DIO

DCLK

DIO

VDD

C2

7

AS5134

VSS

8

D13 D12

100n

21

20

t9

DIO read

t10

D0

DIO write

VDD

Output

Output

Input

Micro Controller

VSS

VSS

command phase data phase

1

t1

2

3

10k…

100k

4

5

CS

6

D15 D14 D1

Table 6. 2-or 3-wire Read-only Serial Bit Sequence (21bit read)

Read

D20 D19 D18 D17 D16 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

00000lock

AGC Angle

D5 D4 D3 D2 D1 D0 D8 D7 D6 D5 D4 D3 D2 D1 D0

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AS5134

Data Sheet - Det ai led D es cri pt ion

Serial 2-Wire Connection (R/W Mode)

By connecting the configuration input C2 to VDD, the AS5134 is configured to 2-wire data transmission mode. Only
Clock (DCLK) and Data (DIO) signals are required. A Chip Select (CS) signal is automatically generated by the DX
output, when a time-out of DCLK occurs (typ. 20µs).

Note: Read-only mode is also possible in this configuration.

Figure 6. 2-Wire R/W Mode

+5V

VDD

VDD

VDD

C2

AS5134

DCLK

DX

CS

DIO

DIO

Output

I/O

Micro Controller

VSS

VSS

command phase data phase

1

t0

2

t1

CMD4

3

CMD3 CMD2

4

5

CMD1

DCLK

DIO

67

t5

CMD0

t6

D15 D14 D1

VSS

8

100n

timeout phase

t

TO

22

DIO read

D0

DIO write

Serial 2-Wire Differential SSI Connection

With the addition of a RS-422 / RS-485 transceiver, a fully differential data transmission, according to the 21-bit SSI
interface standard is possible. To be compatible with this standard, the DCLK signal must be inverted. This is done by
reversing the Data+ and Data- lines of the transceiver.

Note: This type of transmission is read-only.

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AS5134

Data Sheet - Det ai led D es cri pt ion

Figure 7. 2-Wire SSI Read-only Mode

+5V

VDD

DCLK

DI

VSS

VDD

MAX 3081 or similar

DCLK

Output

Micro Controller

DI

Input

VSS

1

2

D+

D-

D+

D-

3

4

D-

D+

D+

D-

5

DCLK

DIO

6

C2

VDD

AS5134

100n

VSS

7

8

20

21

timeout

t

TO

D15

D14

D1 D0

Read

D20 D19 D18 D17 D16 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0

00000lock

AGC Angle

D5 D4 D3 D2 D1 D0 D8 D7 D6 D5 D4 D3 D2 D1 D0

1-Wire PWM Connection

This configuration uses the least number of wires: only one line (PWM) is used for data, leaving the total number of
connection to three, including the supply lines. This type of configuration is especially useful for remote sensors. Ultra
Low Power Mode is not possible in this configuration, as there is no bi-directional data transmission. If the AS5134
angular data is invalid, the PWM output will remain at low state. Pins that are not shown may be left open.

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AS5134

Data Sheet - Det ai led D es cri pt ion

Figure 8. Data Transmission with Pulse Width Modulated (PWM) Output

+5V
VDD

C2

VDD

100n

VSS

exit

VSS

VDD

Micro Controller

Input

VSS

lock

init

CS

AS5134

PWM

t_pwm

pwm - state

The PWM signal will be generated from the actual stored angle information. The zero-angle corrected value is buffered
and fixed until the next PWM-sequence is started. To ease the filtering of the PWM signal, a minimum pulse width is
implemented in the protocol.

Analog Output

This configuration is similar to the PWM connection (only three lines including supply are required). With the addition of
a lowpass filter at the PWM output, this configuration produces an analog voltage that is proportional to the angle. This
filter can be either passive (as shown in Figure 9) or active. The lower the bandwidth of the filter, the less ripple of the
analog output can be achieved. If the AS5134 angular data is invalid, the PWM output will remain at low state and thus
the analog output will be 0V. Pins that are not shown may be left open.

Figure 9. Data Transmission with Pulse Width Modulated (PWM) Output

+5V
VDD

100n

VSS

CS

AS5134

C2

VDD

PWM

VSS

>=1µF

>=4k7>=4k7

>=1µF

Analog

out

5V

0V

Analog out

PWM out

Angle

0º

180º

360º

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AS5134

Data Sheet - Det ai led D es cri pt ion

Quadrature A/B/Index Output

The phase shift between channel A and B indicates the direction of the magnet movement. Channel A leads channel B
at a clockwise rotation of the magnet (top view) by 90 electrical degrees. Channel B leads channel A at a counter­clockwise rotation.

Figure 10. Incremental Output Modes

Mechanical

Zero Position

Hyst=
2LSB

Quad A/B/Index-Mode

A

B

Index

Mechanical

Zero Position

Index=0

1 LSB

max.

3 LSB

Rotation Direction

Change

Table 7. Programming Options for the Quadrature Signals A/B/Index

Abi (13:12) Function: output multiplexer for pin A,B,I

00 A → pin A, B → pin B, I(index) → pin I default value)

0 1 step → pin A, direction → pin B, I(index) → pin I

1 0 pulse → pin A, direction → pin B, I(index) → pin I

1 1 off: LO → pin A, LO → pin B, LO → pin I

Brushless DC Motor Commutation Mode

The BLDC signals will be used to control the electrical angle information – according to the amount of pole pairs and
the actual mechanical angle position. Refer Figure for an example of n_pole_pairs:=2. For the programming, refer to

Serial Synchronous Interface (SSI) on page 19.

Figure 11. Commutation Mode

α

U

V

W

electrical

pole pair : 2

0

0

:= α

mechanical*npole_pairs

60

30

120

60 90

180

240 300

150

0

180120

60

210

120

240

180

angle electrical

angle mechanical

270

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AS5134

Data Sheet - Det ai led D es cri pt ion

Table 8. Programming Options for the Commutation Signals U/V/W

uvw (11:9) Function

0 0 0 BLDC Pole Pairs : 1 → electrical angle of 60º := mechanical angle: 60º

0 0 1 BLDC Pole Pairs : 2 → electrical angle of 60º := mechanical angle: 30º

0 1 0 BLDC Pole Pairs : 3 → electrical angle of 60º := mechanical angle: 20º

0 1 1 BLDC Pole Pairs : 4 → electrical angle of 60º := mechanical angle: 15º

1 0 0 BLDC Pole Pairs : 5 → electrical angle of 60º := mechanical angle: 12º

1 0 1 BLDC Pole Pairs : 6 → electrical angle of 60º := mechanical angle: 10º

111 off → LO pad U,V,W, PWM

Daisy Chain Mode

The angle information from the device and the setup for the device is handled over the digital interface. A special port
(Dx) can be used to implement a daisy chain mode. Depending on the configuration, it is possible to implement a two
wire or a three wire mode. In the three wire mode, each communication starts with the rising edge of the chip select
signal. The Port Dx is used to transfer the chip select information from one device to the next. Refer to Figure 12 and

Figure 13. In the two wire interface mode, a timeout logic ensures that the digital interface will be reset if there is no

clock source available for a certain time. The synchronization between the internal free running analog clock oscillator
and the external used digital clock source for the digital interface is done in a way that the digital clock frequency can
vary in a wide range.

Remark: Reset for the digital interface:

3 wire mode → via chip select

2 wire mode → via timeout

Port Symbol Function

chip select

DCLK

bidirectional data input
output

Daisy Chain Port

CS

DCLK

DIO

Dx

Indicates the start of a new access cycle to the device
CS = LO → reset of the digital interface.

Clock source for the communication over the digital interface. The
maximum and minimum frequency depends on the mode.

Command and data information over one single line. The first bit of
the command defines a read or write access.

This port enables the daisy chain configuration of several devices.

Three wire mode: Indicates the end of an interface cycle. Dx can be
used as the chip select signal for the next device in the chain.

Two wire mode: Will be set with the first falling edge of DCLK and
hence, indicates a running clock; it will be cleared at the end of the
command sequence or after a timeout phase. Dx can be used as a
chip select signal in the two wire mode.

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AS5134

Data Sheet - Det ai led D es cri pt ion

Waveform – Digital Interface @ Three Wire Daisy Chain Mode

Note: Defined if the Pin C2 is set to LO @ all devices

Figure 12. Three Wire Daisy Chain Mode

DCLK

CS(1)

CS_INT(1)

DX(1) = CS(2)

CS_INT(2)

DX(2) = CS(3)

CS_INT(3)

CMD(1)

C4 C3 C2 C1 C0 D15D14 D13 D0 C4 C0 D15D14 D0 C4

DIO

CS

CLK

Data(1)

DX DX DX

DIO

CLK

CS

C2 C2 C2

LO LO LO

CMD(2) Data(2) CMD(3) Data(3)

DX(1) DX(2)

DIO

CLK

CS

DIO

CLK

CS

C0 D15D14

CMD(1)

D0

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AS5134

Data Sheet - Det ai led D es cri pt ion

Waveform – Digital Interface @ Two Wire Daisy Chain Mode

Note: Defined, if the Pin C2 is set to LO @ all devices except the last one where the Pin C2 is set to HI

Figure 13. Two Wire Daisy Chain Mode

t14_2

CMD(2) Data(2) CMD(3) Data(3)

C0 D15 D14

DCLK

DX(3)

CS(1)

CMD(1)

C4 C3 C2 C1 C0 D15 D14 D13 D0 C4 C0 D15 D14 D0 C4

Data(1)

D0

CMD(1)

C4

CS_INT(1)

DX(1) = CS(2)

CS_INT(2)

DX(2) = CS(3)

CS_INT(3)

t16

DIO

DCLK

t14_3

DX(1) DX(2)

CS

DIO

CLK

DX

C2 C2 C2

LO

CS

DIO

CLK

DX DX

LO LO

CS

DIO

CLK

DX(3)

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AS5134

Data Sheet - Det ai led D es cri pt ion

Serial Synchronous Interface (SSI)

Table 9. Commands of the SSI in Normal Mode

Digital interface @ normal mode

# cmd bin mode 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

WRITE CONFIG 1

23

SET MT COUNTER

20

EN PROG

16

RD MT COUNTER

4

RD_ANGLE

0

EN PROG: Enables the access to the OTP register.

WRITE CONFIG: LP HI activates the sleep mode of the AS5134. The power consumption is significantly reduced. LP

LO returns to normal operation mode. During sleep mode, the lock bit in command 0 and command 1 is LO.

RD_MT Counter: Command for read out of multi turn register.

RD_ANGLE: Command for read out of angle value and AGC value (agc). “Lock” indicates a locked ADC.

tst: Test bits for internal testing.

Hyst (11:10): Digital Hysteresis can be set via the digital interface 0,1,2 (default) 3 LSB; “On” after power-on reset

10111 write LP tst tst tst Hyst<1:0> tst tst tst

10100 write multi-turn-counter <8:0>

10000 write 1 0 0 0 1 1 0 0 1 0 1 0 1 1 1 0

00100 read multi-turn-counter <8:0> tst

00000 read lock_adc agc <5:0> angle <8:0>

Hyst Function

0 0 2 LSB (default value)

01 1

10 3

11 0

SET MT COUNTER: Command for setting the Multi Turn Counter to a defined value.

LP: Default "0"; "1" for using the low power function.

lock_adc: Indicates that the tracking adc is in a locked status. Note that for valid angle conditions, the magnetic field

has to be in a certain range, which is indicated by the agc_counter value.

Table 10. Commands of the SSI in Extended Mode

Digital interface @ extended mode

number of bits 2 18 1 1 4 2 1 4 2 3 1

# cmd bin mode

31 W RIT E OTP 11111

25 PROG_OTP 11001

15 REA D_OT P 0 1111

9 READ ANA 01001

extded

write

extded

write

extded

read

extded

read

61..6059..

tst ID hyst_2x tst tst tst FM tst tst tst

tst ID hyst_2x LP tst tst LP tst tst tst

tst ID hyst_2x LP tst tst LP tst tst tst

tst ID hyst_2x LP tst tst LP tst tst tst

42

41 40

39..3635..
32

30..2726..2524..

31

22

21

lock_otp

(*)

lock_otp

(*)

lock_otp

(*)

lock_otp

(*)

Customer Settings

4 1 2 2 3 9

20..1
7

r_ad

d

r_ad

d

r_ad

d

r_ad

d

15..1413..1211..

16

sensi

r_bit

tivity

sensi

r_bit

tivity

sensi

r_bit

tivity

sensi

r_bit

tivity

9

abi uvw

abi uvw

abi uvw

abi uvw

8..0

zero

angle

zero

angle

zero

angle

zero

angle

WRITE OTP: Writing of the OTP register. The written data is volatile. “Zero Angle” is the angle, which is set for zero
position. “Sensitivity” is the gain setting in the signal path. “Redundancy” is the number of bits, which allows the
customer to overwrite one of the customer OTP bits <0:15>.

PROG_OTP: Programming of the OTP register. Only Bits <0:20> can be programmed by the customer. The internal
factory settings are locked by an “internal lock bit” and cannot be programmed.

READ_OTP: Read out the content of the OTP register. Data written by WRITE_OTP and PROG_OTP is read out.

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AS5134

Data Sheet - Det ai led D es cri pt ion

READ ANA: Analog read out mode. The analog value of every OTP bit is available at pin 1 (PROG), which allows for
a verification of the fuse process. No data is available at the SSI.

tst: Test bits for internal testing

ID (59:42): Chip identifier to track the device in the field

hyst_2x (41): Increase the hysteresis two times (default = “0”, 2x = “1”)

FM (31): Fast mode → increase the oscillator frequency by 10%

lock_otp (21): To disable the programming of the factory bits – write access is still possible

r_add (20:17): The following OTP bits can be modified according to the requirements of the application.

r_bit (16): Redundancy bit (functionality is only implemented in the user region)

Sensitivity (15:14): Trim bit for the gain of the amplifier after the demodulator

abi (13:12): Mode selection for the incremental signals

uvw (11:9): Number of poles of the brush less dc motor - impact to the uvw signals

zero angle (8:0): Trim bit for the zero angle information

LP: Enables the low power mode to reduce the current consumption - digital registers are not reseted.

Notes:

1. Empty fields should be described with “logical 0”.

2. These bits will be deleted during power down or sleep mode to ensure that the user is able to detect that the
read out angle value is computed after the wake up sequence.

AS5134 Programming

The AS5134 offers the following user programmable options:

 Zero Position Programming

This programming option allows the user to program any rotation angle of the magnet as the new zero position. This
useful feature simplifies the assembly process as the magnet does not need to be mechanically adjusted to the
electrical zero position. It can be assembled in any rotation angle and later matched to the mechanical zero position by
zero position programming. The 8,5-bit user programmable zero position can be applied both temporarily (command
WRITE OTP, #31) or permanently (command PROG OTP, #25).

 Magnetic Field Optimization

This programming option allows the user to match the vertical distance of the magnet with the optimum magnetic field
range of the AS5134 by setting the sensitivity level. The 2-bit user programmable sensitivity setting can be applied
both temporarily (command WRITE OTP, #31) or permanently (command PROG OTP, #25).

 Low Power Mode

Low Power Mode is a power saving mode with fast start-up. In Low Power Mode, all internal digital registers are frozen
and the power consumption is reduced to max. 1,5 mA. Start-up from this mode to normal operation can be
accomplished within 250µs. This mode is recommended for applications, where low power, but fast start-up and short
reading cycle intervals are required.

OTP Programming Connection

Programming of the AS5134 OTP memory does not require a dedicated programming hardware. The programming
can be simply accomplished over the serial 3-wire interface(see Figure 14) or the optional 2-wire interface(see Figure

6). For permanent programming (command PROG OTP, #25), a constant DC voltage of 8.0 – 8.5V (=100mA) must be

connected to pin 1 (PROG). For temporary OTP write (“soft write”; command WRITE OTP, #31), the programming
voltage is not required. The capacitors must be as close as possible to the pin, to ensure that a serial inductance of
50nH is not to be exceeded. The 50nH inductance could translate into a cable length of approximately 5cm.

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AS5134

Data Sheet - Det ai led D es cri pt ion

Figure 14. OTP Programming Connection

+5V

VDD

VSS

Micro Controller

VDD

VSS

V

zapp

100nF

Output

Output

I/O

C1

8.0 – 8.5V

+

10µF100n

-

maximum

parasitic cable

inductance

L<50nH

C2

10µF

VDD

CS

DCLK

DIO

PROG

AS5134

VSS

C2

V

SUPPLY

100n

VDD

V

prog

PROG

GND

PROM Cell

Programming Verification

After programming, the programmed OTP bits may be verified in two ways:

By Digital Verification: This is simply done by sending a READ OTP command (#15). The structure of this register is
the same as for the OTP PROG or OTP WRITE commands.

By Analog Verification: By sending an ANALOG OTP READ command (#9), pin PROG becomes an output, sending
an analog voltage with each clock, representing a sequence of the bits in the OTP register. A voltage of <500mV
indicates a correctly programmed bit (“1”) while a voltage level between 2.2V and 3.5V indicates a correctly
unprogrammed bit (“0”). Any voltage level in between indicates improper programming.

Figure 15. Analog OTP Verification

+5V

VDD

CS

DCLK

DIO

PROG

VDD

AS5134

C2

100n

VSS

VSS

VDD

Output

Output

I/O

Micro Controller

VSS

8.0 – 8.5V

V

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AS5134

Data Sheet - Det ai led D es cri pt ion

Figure 16. Extended Operation Mode (for OTP access only)

CMD_PHASE DATA_PHASE_EXTENDED

DCLK

CS

DIO

DIO

DIO

t0 t1

t5

t3

HI

t4

CMD0CMD4 CMD2

t6

D61

D61

t7

t8

D60

t11

t12

D60

D0

D0

t9

CMD

t10

READ

t10

WRITE

AS5134 Status Indicators

Lock Status Bit

The Lock signal indicates, whether the angle information is valid (ADC locked, Lock = high) or invalid (ADC unlocked,
Lock = low). To determine a valid angular signal at best performance, the following indicators should be set:

Lock = 1

AGC = >00H and < 2FH

Note: The angle signal may also be valid (Lock = 1), when the AGC is out of range (00H or 2FH), but the accuracy of

the AS5134 may be reduced due to the out of range condition of the magnetic field strength.

Magnetic Field Strength Indicators

The AS5134 is not only able to sense the angle of a rotating magnet, it can also measure the magnetic field strength
(and hence the vertical distance) of the magnet. This additional feature can be used for several purposes:

- as a safety feature by constantly monitoring the presence and proper vertical distance of the magnet

- as a state-of-health indicator, e.g. for a power-up self test

- as a pushbutton feature for rotate-and-push types of manual input devices

The magnetic field strength information is available in two forms:

Magnetic Field Strength Software Indicator

The serial data that is obtained by command READ ANGLE contains the 6-bit AGC information. The AGC is an
automatic gain control that adjusts the internal signal amplitude obtained from the Hall elements to a constant level. If
the magnetic field is weak, e.g. with a large vertical gap between magnet and IC, with a weak magnet or at elevated
temperatures of the magnet, the AGC value will be high. Likewise, the AGC value will be lower when the magnet is
closer to the IC, when strong magnets are used and at low temperatures.

The best performance of the AS5134 will be achieved when operating within the AGC range. It will still be operational
outside the AGC range, but with reduced performance especially with a weak magnetic field due to increased noise.

Factors Influencing the AGC Value

In practical use, the AGC value will depend on several factors:

 The initial strength of the magnet. Aging magnets may show a reducing magnetic field over time which results in

an increase of the AGC value. The effect of this phenomenon is relatively small and can easily be compensated by
the AGC.

 The vertical distance of the magnet. Depending on the mechanical setup and assembly tolerances, there will

always be some variation of the vertical distance between magnet and IC over the lifetime of the application using
the AS5134. Again, vertical distance variations can be compensated by the AGC.

 The temperature and material of the magnet. The recommended magnet for the AS5134 is a diametrically mag-

netized, 5-6mm diameter NdFeB (Neodymium-Iron-Boron) magnet. Other magnets may also be used as long as

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AS5134

Data Sheet - Det ai led D es cri pt ion

they can maintain to operate the AS5134 within the AGC range. Every magnet has a temperature dependence of
the magnetic field strength. The temperature coefficient of a magnet depends on the used material. At elevated
temperatures, the magnetic field strength of a magnet is reduced, resulting in an increase of the AGC value. At low
temperatures, the magnetic field strength is increased, resulting in a decrease of the AGC value. The variation of
magnetic field strength over temperature is automatically compensated by the AGC.

OTP Sensitivity Adjustment

To obtain best performance and tolerance against temperature or vertical distance fluctuations, the AGC value at
normal operating temperature should be in the middle between minimum and maximum, hence it should be around
100000 (20H). To facilitate the “vertical centering” of the magnet+IC assembly, the sensitivity of the AS5134 can be
adjusted in the OTP register in 4 steps. A sensitivity adjustment is recommended, when the AGC value at normal
operation is close to its lower limit (around 00H). The default sensitivity setting is 00
will increase the sensitivity (see Table 3).

= low sensitivity. Any value >00H

H

Multi Turn Counter

A 9-bit register is used for counting the magnet’s revolutions. With each zero transition in any direction, the output of a
special counter is incremented or decremented. The initial value after reset is 0 LSB. The multi turn value is encoded
as complement on two. Clockwise rotation gives increasing angle values and positive turn count. Counter clockwise
rotation exhibits decreasing angle values and a negative turn count respectively.

Bit Code Decimal Value

011111111 256

--- ---

01111111 127

--- ---

00000011 +3

00000010 +2

00000001 +1

00000000 0

11111111 -1

11111110 -2

11111101 -3

--- ---

10000000 -128

--- ---

100000000 -255

The counter output can be reset by using command 20 – SET MT Counter. It is immediately reset by the rising clock
edge of this bit. Any zero crossing between the clock edge and the next counter readout changes the counter value.

High Speed Operation

The AS5134 is using a fast tracking ADC (TADC) to determine the angle of the magnet. The TADC is tracking the
angle of the magnet with cycle time of 2µs (typ. 1.4). Once the TADC is synchronized with the angle, it sets the LOCK
bit in the status register. In worst case, usually at start-up, the TADC requires up to 255 steps (255 * 2µs = 510µs) to
lock. Once it is locked, it requires only one cycle [2µs (typ. 1.4)] to track the moving magnet. The AS5134 can operate
in locked mode at rotational speeds up to min. 25.000 rpm.

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AS5134

Data Sheet - Det ai led D es cri pt ion

In Low Power Mode, the position of the TADC is frozen. It will continue from the frozen position once it is powered up
again. If the magnet has moved during the power down phase, several cycles will be required before the TADC is
locked again. The tracking time to lock in with the new magnet angle can be roughly calculated as:

t

LOCK

1.406

(EQ 1)

2μ s∗NewAngle OldAngle–

--------------------------------------------------------------------------

=

Where:

= Time required to acquire the new angle after power up from one of the reduced power modes [µs]

t

LOCK

OldAngle = Angle position when one of the reduced power modes is activated [º]
NewAngle = Angle position after resuming from reduced power mode [º]

Propagation Delay

The Propagation delay is the time required from reading the magnetic field by the Hall sensors to calculating the angle
and making it available on the serial or PWM interface. While the propagation delay is usually negligible on low
speeds, it is an important parameter at high speeds. The longer the propagation delay, the larger becomes the angle
error for a rotating magnet as the magnet is moving while the angle is calculated. The position error increases linearly
with speed. The main factors that contribute to the propagation delay are discussed in detail further in this document.

ADC Sampling Rate

For high speed applications, fast ADC’s are essential. The ADC sampling rate directly influences the propagation
delay. The fast tracking ADC used in the AS5134 with a tracking rate of only 1.4 µs (typ) is a perfect fit for both high
speed and high performance.

Chip Internal Lowpass Filtering

A commonplace practice for systems using analog-to-digital converters is to filter the input signal by an anti-aliasing
filter. The filter characteristic must be chosen carefully to balance propagation delay and noise. The lowpass filter in the
AS5134 has a cutoff frequency of typ. 23.8kHz and the overall propagation delay in the analog signal path is typ.

15.6µs.

Digital Readout Rate

Aside from the chip-internal propagation delay, the time required to read and process the angle data must also be
considered. Due to its nature, a PWM signal is not very usable at high speeds, as you get only one reading per PWM
period. Increasing the PWM frequency may improve the situation but causes problems for the receiving controller to
resolve the PWM steps. The frequency on the AS5134 PWM output is typ. 1.33kHz with a resolution of 2µs/step. A
more suitable approach for high speed absolute angle measurement is using the serial interface. With a clock rate of
up to 6MHz, a complete set of data (21bits) can be read in >3.5µs.

Total Propagation Delay of the AS5134

The total propagation delay of the AS5134 is the delay in the analog signal path and the tracking rate of the ADC:

15.6 + 1.4 = 17µs(typ) (EQ 2)

If only the SIN-/COS-outputs are used, the propagation delay is the analog signal path delay only (typ. 15.6µs).

Position Error Over Speed:

The angle error over speed caused by the propagation delay is calculated as:

Δθ

= rpm * 6 * 17 * E-6 in degrees (EQ 3)

pd

In addition, the anti-aliasing filter causes an angle error calculated as:

θ

= ArcTan [rpm / (60 * f0)] (EQ 4)

Δ

lpf

Table 11. Examples of the Overall Position Error caused by Speed (includes both propagation delay and filter delay)

Speed (rpm)

Total Position Error (Δθ

100 0,0175º

1000 0,175º

10000 1,75º

pd +

Δ

θ

)

lpf

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AS5134

Data Sheet - Det ai led D es cri pt ion

Low Power Mode

The target of this mode is to reduce the long time power consumption of the device for battery powered applications,
without losing the actual angle information.

In Low Power Mode, the AS5134 is inactive. The last state (for e.g. the angle, AGC value, etc.) is frozen and the chip
starts from this frozen state when it resumes active operation. This method provides much faster start-up than a “cold
start” from zero. If the AS5134 is cycled between active and reduced current mode, a substantial reduction of the
average supply current can be achieved. The minimum dwelling time is <0.5 ms. The actual active time depends on
how much the magnet has moved while the AS5134 was in reduced power mode. The angle data is valid, when the
status bit LOCK has been set. Once a valid angle has been measured, the AS5134 can be put back to reduced power
mode. The average power consumption can be calculated as:

∗

I

tonI

active

---------------------------------------------------------------------

=

I

avg

+

powerdown

t

+

ontoff

Where:

= Average current consumption

I

avg

= Current consumption in active mode

I

active

= I

I

power_down

= Time period during which the chip is operated in active mode

t

on

t

= Time period during which the chip is in reduced power mode

off

: Current consumption in reduced power mode (max. 120µA)

off

To access the Low Power Mode, the bit ‘LP’ <15> of the digital interface has to be set to “1”.

∗

t

off

sampling interval = t

on

+ t

off

(EQ 5)

Figure 17. Low Power Mode Connection

C1

100n

VDD

S

R1

t

on

I

on

t

off

I

off

N

CS

DCLK

DIO

VDD

on/off

Micro

Controller

+5V

VDD

AS5134

VSS

Reducing Power Supply Peak Currents

An optional RC-filter (R1/C1) may be added to avoid peak currents in the power supply line when the AS5134 is
toggled between active and reduced power mode. R1 must be chosen such that it can maintain a VDD voltage of 4.5 –

5.5V under all conditions, especially during long active periods when the charge on C1 has expired. C1 should be
chosen such that it can support peak currents during the active operation period. For long active periods, C1 should be
large and R1 should be small.

C2

VSS

VSS

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AS5134

Data Sheet - Det ai led D es cri pt ion

Magnet Diameter and Vertical Distance

Note: Following is just an abstract taken from the elaborate application note on the Magnet.

For more detailed information, please visit our homepage www.austriamicrosystems.com → Magnetic Rotary

Encoders → Magnet Application Notes

The Linear Range

The Hall elements used in the AS5000-series sensor ICs are sensitive to the magnetic field component Bz, which is
the magnetic field vertical to the chip surface. Figure 18 shows a 3-dimensional graph of the Bz field across the surface
of a 6mm diameter, cylindrical NdFeB N35H magnet at an axial distance of 1mm between magnet and IC.

The highest magnetic field occurs at the north and south poles, which are located close to the edge of the magnet, at
~2.8mm radius (see Figure 19). Following the poles towards the center of the magnet, the Bz field decreases very
linearly within a radius of ~1.6mm. This linear range is the operating range of the magnet with respect to the Hall
sensor array on the chip. For best performance, the Hall elements should always be within this linear range.

Figure 18. 3D-Graph of Vertical Magnetic Field of a 6mm Cylindrical Magnet

BZ; 6mm magnet @ Z=1mm

Bz [mT]

area of X- Y-misalignment from
center: ±0.5mm

circle of Hall elements on
chip

Y -displacement [mm]

X -displacement [mm]

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AS5134

Data Sheet - Det ai led D es cri pt ion

As shown in Figure 19 (grey zone), the Hall elements are located on the chip at a circle with a radius of 1.1mm. Since
the difference between two opposite Hall sensors is measured, there will be no difference in signal amplitude when the
magnet is perfectly centered or if the magnet is misaligned in any direction as long as all Hall elements stay within the
linear range.

For the 6mm magnet (shown in Figure 19), the linear range has a radius of 1.6mm, hence this magnet allows a radial
misalignment of 0.5mm (1.6mm linear range radius; 1.1mm Hall array radius). Consequently, the larger the linear
range, the more radial misalignment can be tolerated. By contrast, the slope of the linear range decreases with
increasing magnet diameter, as the poles are further apart. A smaller slope results in a smaller differential signal, which
means that the magnet must be moved closer to the IC (smaller airgap) or the amplification gain must be increased,
which leads to a poorer signal – to – noise ratio. More noise results in more jitter at the angle output. A good
compromise is a magnet diameter in the range of 5…8mm.

Small Diameter Magnet (<6mm) Large Diameter Magnet (>6mm)

+++ stronger differential signal =

good signal / noise ratio,

larger airgaps

--- shorter linear range =

smaller horizontal misalignment area

+++ wider linear range =

larger horizontal misalignment area

-- weaker differential signal =
poorer signal / noise ratio,

smaller airgaps

Figure 19. Vertical Magnetic Field across the center of a Cylindrical Magnet

Bz; 6mm magnet @ y=0; z=1mm

Hall elements (side view)

X -displacement [mm]

Bz [mT]

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AS5134

%

Data Sheet - Det ai led D es cri pt ion

Magnet Thickness

Figure 20 shows the relationship of the peak amplitude in a rotating system (essentially the magnetic field strength of

the Bz field component) in relation to the thickness of the magnet. The X-axis shows the ratio of magnet thickness (or
height) [h] to magnet diameter [d] and the Y-axis shows the relative peak amplitude with reference to the
recommended magnet (d=6mm, h=2.5mm). This results in an h/d ratio of 0.42.

Figure 20. Relationship of Peak Amplitude vs. Magnet Thickness

Bz amplitude vs. magnet thickness

of a cylindrical diametric magnet with 6mm diameter

160%

140%

]

120%

100%

80%

60%

d= 6mm x h= 2.5mm ref. magnet:

40%

Relative peak amplitude [

20%

0%

0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8

As the graph in Figure 20 shows, the amplitude drops significantly at h/d ratios below this value and remains relatively
flat at ratios above 1.3.

Therefore, the recommended thickness of 2.5mm (@6mm diameter) should be considered as the low limit with
regards to magnet thickness.

It is possible to get 40% or more signal amplitude by using thicker magnets. However, the gain in signal amplitude
becomes less significant for h/d ratios >~1.3. Therefore, the recommended magnet thickness for a 6mm diameter
magnet is between 2.5 and ~8 mm.

h/d = 0.42
Rel. amplitude = 100%

thickness to diameter [h/d] ratio

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Data Sheet - Det ai led D es cri pt ion

Axial Distance (Airgap)

Figure 21. Sinusoidal Magnetic Field generated by the Rotating Magnet

B

vertical

field

0

360º

The recommended magnetic field, measured at the chip surface on a radius equal to the Hall sensor array radius (typ.

1.1mm) should be within a certain range. This range lies between 45 and 75mT or between 20 and 80mT, depending
on the encoder product.

Linear position sensors are more sensitive as they use weaker magnets. The allowed magnetic range lies typically
between 5 and 60mT.

Angle Error vs. Radial and Axial Misalignment

The angle error is the deviation of the actual angle vs. the angle measured by the encoder. There are several factors in
the chip itself that contribute to this error, mainly offset and gain matching of the amplifiers in the analog signal path. On
the other hand, there is the nonlinearity of the signals coming from the Hall sensors, caused by misalignment of the
magnet and imperfections in the magnetic material.

Ideally, the Hall sensor signals should be sinusoidal, with equal peak amplitude of each signal. This can be maintained,
as long as all Hall elements are within the linear range of the magnetic field Bz (see Figure 19).

Accuracy

Accuracy is defined as the error between the measured angle and the actual angle. It is influenced by several factors:

 the non-linearity of the analog-digital converters

 internal gain and mismatch errors

 non-linearity due to misalignment of the magnet

Misalignment of the magnet further reduces the accuracy. Figure 22 shows an example of a 3D-graph displaying non­linearity over XY-misalignment. The center of the square XY-area corresponds to a centered magnet. The X- and Y­axis extends to a misalignment of ±1mm in both directions. The total misalignment area of the graph covers a square
of 2x2 mm (79x79mil) with a step size of 200µm. The gap between surface and magnet is z=500µm.

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AS5134

Data Sheet - Det ai led D es cri pt ion

Figure 22. 3D Graph Displaying Non-Linearity Over XY-Misalignment

Linea rity Error over XY-misalignm ent [°]

-1000

1.5

1

0.5

2.5

2

3.5

3

3-3.5

2.5-3

2-2.5

1.5-2

1-1.5

0.5-1

0-0.5

-600

-200

10000

600

200

200

-600

-200

X

Y

For volume production, the placement tolerance of the IC within the package (±0.235mm) must also be taken into
account. The total nonlinearity error over process tolerances, temperature and a misalignment circle radius of 0.25mm
is specified better than ±2 degrees.

The magnet used for this measurement is a cylindrical NdFeB (Bomatec® BMN-35H) magnet with 6mm diameter and

2.5mm in height.

Mounting the Magnet

Generally, for on-axis rotation angle measurement, the magnet must be mounted centered over the IC package. How­ever, the material of the shaft into which the magnet is mounted, is also of big importance.

Magnetic materials in the vicinity of the magnet will distort or weaken the magnetic field being picked up by the Hall
elements and cause additional errors in the angular output of the sensor.

600

1000

-1000

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Data Sheet - Det ai led D es cri pt ion

Figure 23. Magnetic Field Lines in Air

Figure 23 shows the ideal case with the magnet in air. No magnetic materials are anywhere nearby.

Figure 24. Magnetic Field Lines in Plastic or Copper Shaft

If the magnet is mounted in non-magnetic material, such as plastic or diamagnetic material, such as copper, the mag­netic field distribution is not disturbed. Even paramagnetic material, such as aluminium may be used. The magnet may
be mounted directly in the shaft (see Figure 24).

Note: Stainless steel may also be used, but some grades are magnetic. Therefore, steel with magnetic grades

should be avoided.

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AS5134

Data Sheet - Det ai led D es cri pt ion

Figure 25. Magnetic Field Lines in Iron Shaft

If the magnet is mounted in a ferromagnetic material, such as iron, most of the field lines are attracted by the iron and
flow inside the metal shaft (see Figure 25). The magnet is weakened substantially.

This configuration should be avoided!

Figure 26. Magnetic Field Lines with Spacer between Magnet and Iron Shaft

If the magnet has to be mounted inside a magnetic shaft, a possible solution is to place a non-magnetic spacer
between shaft and magnet, as shown in Figure 26. While the magnetic field is rather distorted towards the shaft, there
are still adequate field lines available towards the sensor IC. The distortion remains reasonably low.

Summary

 Small diameter magnets (<6mm Ø) have a shorter linear range and allow less lateral misalignment. The steeper

slope allows larger axial distances.

 Large diameter magnets (>6 mm Ø) have a wider linear range and allow a wider lateral misalignment. The flatter

slope requires shorter axial distances.

 The linear range decreases with airgap; Best performance is achieved at shorter airgaps.

 The ideal vertical distance range can be determined by using magnetic range indicators provided by the encoder

ICs. These indicators are named MagInc, MagDec, MagRngn, or similar, depending on product.

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AS5134

Data Sheet - App licat io n I nf orm at ion

8 Application Information

Benefits of AS5134

 Complete system-on-chip, no angle calibration required

 Flexible system solution provides absolute serial, ABI, UVW and PWM outputs

 Ideal for applications in harsh environments due to magnetic sensing principle

 High reliability due to non-contact sensing

 Robust system, tolerant to horizontal misalignment, airgap variations, temperature variations and external mag-

netic fields

AS5134 Parameter and Features List

Table 12. Parameter and Features List

Parameter AS5134

Supply Voltage 4.5 to 5.5 V

Resolution 8.5 bit (360 steps, 1º per step)

ABI quadrature: 90 ppr, (default)

Incremental outputs (ABI)

BLDC outputs UVW ; selectable for 1,2,3,4,5,6, pole pairs

Absolute output

Daisy Chain mode Available for 2-wire and 3-wire serial modes

Automotive qualification AEC Q-100, grade 1

Chip Identifier 18 bit

Ambient temperature -40 to +140ºC

ESD protection ±2kV

Propagation delay (in locked state) Max 22µs

Transition noise (rms; 1 sigma) 0.24º

Integral Nonlinearity (INL),
centered magnet

Multiturn Counter

Low power mode

step/direction: 180 ppr (OTP option)
fixed pulse width: 360ppr

Serial 2-wire (DCLK,DIO) with timeout sync
Serial 3-wire (DCLK, CS, DIO)
PWM output

+/-2º

9-bit (+256/-255 turns).
Automatically updated during active mode at every 360º-/0º-

transition in each rotating direction.
The multiturn counter can be accessed over the serial interface

and is reset with a power-on-reset.
It will be frozen at the last valid state in low power mode.

Non-operational. Last status is frozen in Low power mode to
allow low power consumption and fast startup from low power
mode to operating mode.
Serial interface is active in low power mode to allow wakeup
over the serial interface.
PWM, incremental and BLDC outputs are invalid in low power
mode, they remain at their last valid state.
Current consumption in low power mode: typ. 30µA

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AS5134

Data Sheet - App licat io n I nf orm at ion

Table 12. Parameter and Features List

Parameter AS5134

2µs / step. 360º angle range in all modes.
Minimum pos. pulse width (@0º) = 16µs (8 LSB; tbd)
Minimum neg. pulse width (@359º) = 16µs (8 LSB; tbd)
Pulse width @0º = 16µs, Pause = 734µs
Pulse width @1º = 18µs, Pause = 732µs

PWM output

Pulse width @2º = 20µs, Pause = 730µs
………..
Pulse width @359º = 734µs, Pause = 16µs

In case of an error (LOCK = Low), the pulse width is 8 µs (4
LSB), pause = 742µs for all angles.

Incremental ABI interface: 3 pins

Interface hardware

BLDC UWV interface: 3 pins
Absolute interface: 2 or 3 pins
All outputs are available at the same time on separate pins

Maximum speed; no missing codes 25.000 rpm

Alignment tolerance +/- 0.25 mm (reference to package center)

Normal operating Current consumption Typ 14mA; max 22mA

≤1.3 ms from cold start (no AGC),

Power-Up time

≤4.1ms from cold start (AGC locked)
<0.5ms from low power mode

Serial Interface read options

360-step Angle (8.5-bit), 6-bit AGC, 9-bit Multiturn,
ADC Lock

Zero Position Programming in OTP

Incremental mode(quad ABI, step/dir)

Serial interface program options

BLDC pole pairs (1,2,3,4,5,6)
Zero Position
Hall sensor sensitivity

Incremental mode(quad ABI, step/dir)
BLDC pole pairs (1,2,3,4,5,6)

Serial interface write options (temporary write; will
be lost with POR)

Zero Position
Hall sensor sensitivity
Multiturn counter reset to 00
Low power mode (on/off)

IC package SSOP-20

Magnetic range software indicator Field strength (AGC) readable through digital interface

Magnetic input field range [mT] 20 – 80 mT

BLDC Outputs

BLDC outputs 3 separate digital outputs: U,V,W

BLDC pole pair options Selectable for 1,2,3,4,5,6, pole pairs

Hysteresis on BLDC outputs Same as incremental output hysteresis

Switching positions

Pole pairs Switching position steps

160º

230º

320º

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AS5134

Data Sheet - App licat io n I nf orm at ion

Table 12. Parameter and Features List

Parameter AS5134

415º

512º

610º

Incremental Outputs

3 modes:

Incremental modes

Quad AB with Index (2x90 ppr),
Step/direction (1x180 ppr)
Fixed pulse width (360ppr)

Step size 1º

Incremental Hysteresis 0-3LSB; 2LSB (default)

OTP Programming

OTP programming technology Zener Zapping

Zero position, Hall sensor sensitivity
BLDC pole pairs (1,2,3,4,5,6)

OTP programming options

Incremental mode (quad AB, step/dir)
Redundant Address
Chip-Identifier

OTP programming method

Over serial interface and static 8 - 8.5V
Programming voltage at Pin PROG

OTP programming verification Digital and Analog

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AS5134

Z

Z

A

Data Sheet - Pac kage Drawings and Markings

9 Package Drawings and Markings

The device is available in a 20-pin SSOP package.

Figure 27. 20-pin SSOP Package Drawings

Y

A2

A

A1

b

e

YH

PIN 1 Identification

Table 13. 20-pin SSOP Package Dimensions

Symbol

A 1.73 1.86 1.99 0.068 0.073 0.078

A1 0.05 0.13 0.21 0.002 0.005 0.008

A2 1.68 1.73 1.78 0.066 0.068 0.070

b 0.25 - 0.38 0.010 - 0.015

D 7.07 7.20 7.33 0.278 0.284 0.289

E 5.20 5.30 5.38 0.205 0.209 0.212

e 0.65 BSC 0.0256 BSC

H 7.65 7.80 7.90 0.301 0.307 0.311

K0º4º8º0º4º8º

L 0.63 0.75 0.95 0.025 0.030 0.037

X - (10-1)*e + b - - (10-1)e + b -

XH 0.5*X - 0.235 0.5*X 0.5*X + 0.235 0.5*X – 9.25 0.5*X 0.5*X + 9.25

YH 0.5*E – 0.235 0.5*E 0.5E + 0.235 0.5*E – 9.25 0.5*E 0.5*E + 9.25

ZHPT 0.13 0.23 0.33 5.12 9.06 13

ZHPB 0.62 0.77 0.93 24.41 30.31 36.61

Min Typ Max Min Typ Max

-Z

Y

Z

XH

X

D

mm inch

X

c

K

X

E

H

X

L

-Z

YWWIZZ

AS5134

Y

ZHPT

ZHPB

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AS5134

Data Sheet - Pac kage Drawings and Markings

Recommended PCB Footprint

Figure 28. PCB Footprint

Table 14. Recommended Footprint Data

Symbol mm inch

A9.02 0.355

B6.16 0.242

C0.46 0.018

D0.65 0.025

E6.31 0.248

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AS5134

Data Sheet - Ord er ing I nfo rm ati on

10 Ordering Information

The devices are available as the standard products shown in Table 15.

Table 15. Ordering Information

Model Description Delivery Form Package

AS5134C-ZSST High speed up to 25.000 rpm Tape&Reel SSOP20

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AS5134

Data Sheet - Ord er ing I nfo rm ati on

Copyrights

Copyright © 1997-2008, austriamicrosystems AG, Schloss Premstaetten, 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 austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing
in its Term of Sale. austriamicrosystems 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.
austriamicrosystems 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 austriamicrosystems 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
austriamicrosystems 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 austriamicrosystems AG is believed to be correct and accurate. However,
austriamicrosystems 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
austriamicrosystems AG rendering of technical or other services.

Contact Information

Headquarters

austriamicrosystems AG
A-8141 Schloss Premstaetten, Austria

Tel: [phone]
Fax: [phone]

For Sales Offices, Distributors and Representatives, please visit:

http://www.austriamicrosystems.com/contact

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