Osram AS5045B User manual

Product
Document
Published by
ams OSRAM Group

www.ams.com Revision 1.1 / 05.07.2013 page 1/15
AS5045B
12-bit Rotary Position Sensor with Digital Angle
(Interface), PWM and ABI output
User Manual – AS5045B-AB-v1.0

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 2/15
Table of Contents
1General Description .............................................................................................................3
2The AS5045B adapter board ............................................................................................... 3
2.1 Board description ................................................................................................................. 3
2.2 Mounting the AS5045B adapter board.................................................................................4
3AS5045B adapter board and pinout.....................................................................................6
4Operation cases................................................................................................................... 8
4.1 Standalone SSI output mode............................................................................................... 8
4.2 Standalone PWM output mode............................................................................................ 9
4.3 Standalone incremental Output .........................................................................................11
4.4 Daisy chain mode...............................................................................................................12
5Programming the AS5045B ...............................................................................................13
6AS5045B-AB-Hardware.....................................................................................................14
6.1 AS5045B-AB-1.0 Schematics............................................................................................14
6.2 AS5045B –AB –1.0 PCB layout.......................................................................................14
7Copyright............................................................................................................................15
8Disclaimer .......................................................................................................................... 15
9Contact Information............................................................................................................15
Revision History
Revision
Date
Owner
Description
1.0
01.10.2009
Initial revision
1.1
05.07.2013
azen
Updated to new template

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 3/15
1 General Description
The AS5045B is a contactless magnetic rotary encoder for accurate angular measurement over a full
turn of 360°. It is 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 magnet may be placed above or below the IC. This is shown in Figure 1.
Figure 1:
Rotary Position Sensor AS5045B + Magnet
2 The AS5045B adapter board
The AS5045B adapter board is a simple circuit allowing test and evaluation of the AS5045B rotary
position sensor quickly without building a test fixture or PCB.
2.1 Board description
The PCB can be used as standalone unit or attached to a microcontroller. The standalone operation
requires a 5V power supply only; the magnet’s angle can be read on the PWM or analog output.

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 4/15
Figure 2:
AS5045B Adapterboard
2.2 Mounting the AS5045B adapter board
A diametric magnet must be placed over on under the AS5045B encoder, and should be centered on
the middle of the package with a tolerance of 0.5mm.
The airgap between the magnet and the encoder casing should be maintained in the range
0.5mm~2mm. The magnet holder must not be ferromagnetic. Materials as brass, copper, aluminum,
stainless steel are the best choices to make this part.
AS5045B magnetic
position sensor
4 x 2.6mm
mounting holes
J1 connector (Prg,
power supply, serial
interface)
J2 connector (PWM,
and status output)

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 5/15
Figure 3:
AS5045B –AB - mounting and dimension
AS5045B
0.5~2mm
AS5045B
J2J1
GNDPWM Ind B A Mag
INC
GNDPrg 5V 3V3 CSn CLK DO
Mag
DEC
18mm
11mm
28mm
22mm
Diametral
Magnet
4x2.6mm
Magnet
NS

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 6/15
3 AS5045B adapter board and pinout
Figure 4:
AS5045B adapter board connectors and encoder pinout
AS5040
J2J1
GNDPWM Ind B A Mag
INC
GNDPrg 5V 3V3 CSn CLK DO
Mag
DEC
AS5045B-AB-1.0
,
Table 1:
Pin description
Pin#
Board
Pin#
AS5040
Symbol
Board
Type
Description
JP1 - 1
7
GND
S
Supply ground
JP1 - 2
9
DO
DO_T
Data Output of Synchronous Serial Interface
JP1 - 3
10
CLK
DI_ST
ClockInput of Synchronous Serial Interface; Schmitt-Trigger input
JP1 - 4
11
CSn
DI_PU_ST
Chip Select, active low; Schmitt-Trigger input, internal pull-up resistor (~50k)
connect to VSS in incremental mode
JP1 - 5
15
3V3
S
3V-Regulator Output
JP1 - 6
16
5V
S
5V Supply
JP1 - 7
8
Prg
DI_PD
OTP Programming Input and Data Input for Daisy Chain mode. Internal pull-
down resistor (~74k).
May be connected to VSS if programming is not used
JP2 - 1
7
GND
S
Supply ground
JP2 - 2
1
MagINC
DO_OD
Magnet Field Magnitude INCrease; active low, indicates a distance reduction
between the magnet and the device surface.
JP2 - 3
2
MagDEC
DO_OD
Magnet Field Magnitude DECrease; active low, indicates a distance increase
between the device and the magnet
JP2 - 4
3
A
DO
AS5040 –AS5140 –AS5145 (programmed) only
Mode1.x: Quadrature Achannel
Mode2.x: Least Significant Bit
Mode3.x: Usignal (phase1)

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 7/15
Pin#
Board
Pin#
AS5040
Symbol
Board
Type
Description
JP2 - 5
4
B
DO
AS5040 –AS5140 –AS5145 (programmed) only
Mode1.x: Quadrature Bchannel quarter period shift to channel A.
Mode2.x: Direction of Rotation
Mode3.x: Vsignal (phase2)
JP2 - 6
6
Ind
DO
AS5040 –AS5140 –AS5145 (programmed) only
Mode1.x and Mode2.x : Index signal indicates the absolute zero position
Mode3.x: Wsignal (phase3)
AS5045 –AS5145 (unprogrammed)
Mode input, connect to VDD5 (Fast mode) or GND (Slow mode); do not change
during operation
JP2 - 7
12
PWM
DO
Pulse Width Modulation of approx. 1kHz; LSB in Mode3.x
Pin types: DO_OD digital output open drain S supply pin
DI_PD digital input pull-down DO_T digital output /tri-state
DI_PU digital input pull-up ST schmitt-trigger input
DI digital input DO digital output

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 8/15
4 Operation cases
The most complete and accurate solution for a MCU to read the angle of a magnet is the serial
interface.
4.1 Standalone SSI output mode
The serial word contains 12 bits for AS5045B angle value and some other indicator bits like MagINC,
MagDEC, which can be read at the same time.
Figure 5:
Using the analog output with the adapter board
AS5045B
J2J1
GNDPWM Ind B A Mag
INC
GNDPrg 5V 3V3 CSn CLK DO
Mag
DEC
NS
MCU
out in
VDDp
+5V
GND
Regulated
Power
Supply
out
GND
3.3V reg.
Power
Supply
OR
+3V3
GND

User Manual –AS5045B-AB
www.ams.com Revision 1.1 / 05.07.2013 page 9/15
4.2 Standalone PWM output mode
The AS5045B provides a pulse width modulated output (PWM), whose duty cycle is proportional to the
measured angle. The PWM signal (J2 pin #7) with a period of 1025us (1us step) and 5V pulse voltage
can be connected to the capture/timer input of a microcontroller in order to decode the angle value.
Figure 6:
Using the PWM output with the adapter board
AS5045B
J2J1
GNDPWM Ind B A Mag
INC
GNDPrg 5V 3V3 CSn CLK DO
Mag
DEC
NS
MCU
in VDDp
+5V
GND
Regulated
Power
Supply
GND