AS5048A/AS5048B

AS5048A/AS5048B
Magnetic Rotary Encoder
(14-bit Angular Position Sensor)
General Description
The AS5048 is an easy to use 360° angle position sensor with a
14-bit high resolution output. The maximum system accuracy
is 0.05° assuming linearization and averaging is done by the
external microcontroller.
The IC measures the absolute position of the magnet’s rotation
angle and consists of Hall sensors, analog digital converter and
digital signal processing. The absolute position information of
the magnet is directly accessible over a PWM output and can
be read out over a standard SPI or a high speed I²C interface.
AS5048A has a SPI interface, AS5048B I²C interface. Both devices
offer a PWM output.
The zero position can be programmed via SPI or I²C command.
This simplifies the assembly of the complete system because
the zero position of the magnet does not need to be
mechanically aligned. The sensor tolerates misalignment, air
gap variations, temperature variations and as well external
magnetic fields. This robustness and wide temperature range
(-40°C up to +150°C) of the AS5048 makes the IC ideal for
rotation angle sensing in harsh industrial and medical
environments. Several AS5048 ICs can be connected in daisy
chain for serial data read out. An internal voltage regulator
allows the AS5048 to operate at either 3.3 V or 5 V supplies.
Ordering Information and Content Guide appear at end of
datasheet.
Key Benefits & Features
The benefits and features of AS5048A/AS5048B, Magnetic
Rotary Encoder (14-bit Angular Position Sensor) are listed
below:
Figure 1:
Added Value of using AS5048
Benefits
Features
No external programmer needed
Contactless rotary position sensor over 360°
High precision
Immune to external magnetic stray fields
Easy to use
14-bit resolution (0.0219°/LSB)
Low material costs (no shielding)
Standard SPI or I2C interface and PWM
Zero position programmable via SPI or I2C
Temperature range: -40°C to +150°C
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 1
Benefits
Features
3.3V / 5V compliant
Package: 14-pin TSSOP (5 x 6.4mm)
Applications
The applications of AS5048 include:
• Robotic joint position detection
• Industrial motor position control
• Medical robots and fitness equipment
Block Diagram
The functional blocks of this device for reference are
shown below:
Figure 2:
AS5048A Block Diagram
VDD5V
SCK
VDD3V
Register
Setting
LDO
MISO
SPI
MOSI
OTP
CSn
AFE
14-bit A/D
14-bit A/D
ATAN
(CORDIC)
PWM
PWM
AS5048A
AGC
GND
AS5048A/AS5048B – 2
ams Datasheet: 2014-Jun-05 [v1-06]
General Description
Figure 3:
AS5048B Block Diagram
VDD5V
SCL
VDD3V
Register
Setting
LDO
SDA
I2C
A1
OTP
A2
AFE
14-bit A/D
A/D
14-bit
ATAN
(CORDIC)
PWM
PWM
AS5048B
AGC
GND
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 3
Pin Assignment
The AS5048A/AS5048B pin assignments are described below.
Pin Assignment
Figure 4:
TSSOP14 Pin Configuration
14
PWM
SDA
1
14
PWM
CLK
2
13
GND
SCL
2
13
GND
MISO
3
12
VDD3V
A2
3
12
VDD3V
MOSI
4
11
VDD5V
A1
4
11
VDD5V
TEST
5
10
TEST
TEST
5
10
TEST
TEST
6
9
TEST
TEST
6
9
TEST
TEST
7
8
TEST
TEST
7
8
TEST
AS5048B
1
AS5048A
CSn
Figure 5:
TSSOP14 Pin Description for AS5048A
Pin
AS5048A
Pin Type
1
CSn
2
CLK
3
MISO
Digital I/O with schmitt
trigger in the input path
SPI master in/slave out
4
MOSI
Digital input with schmitt
trigger
SPI master out/slave in
5
TEST
6
TEST
7
TEST
8
TEST
9
TEST
10
TEST
11
VDD5V
12
VDD3V
13
GND
14
PWM
Digital input with schmitt
trigger
Analog I/O
AS5048A/AS5048B – 4
Description
SPI chip select - active low
SPI clock input
Test pins. These pins should be grounded to GND.
Positive Supply Voltage, 3.0 to 5.5 V
Supply pad
3.3V Regulator output; internally regulated from VDD.
Connect to VDD for 3V supply voltage. 10μF capacitor
to GND required in 5V operation mode
Negative Supply Voltage (GND)
Digital output – push-pull
Pulse Width Modulation output
ams Datasheet: 2014-Jun-05 [v1-06]
Pi n A s s i g n m e n t
Figure 6:
TSSOP14 Pin Description for AS5048B
Pin
AS5048B
Type
1
SDA
Digital I/O with open drain
output
2
SCL
3
A2
4
A1
5
TEST
6
TEST
7
TEST
8
TEST
9
TEST
10
TEST
11
VDD5V
12
VDD3V
13
GND
14
PWM
Description
Data pin I²C interface
I²C clock input
Digital input with schmitt
trigger
I²C address selection pin 3
I²C address selection pin 4
Analog I/O
Test pins. These pins should be grounded to GND.
Positive Supply Voltage, 3.0 to 5.5 V
Supply pad
3.3V Regulator output; internally regulated from VDD.
Connect to VDD for 3V supply voltage. 10μF capacitor
to GND required in 5V operation mode
Negative Supply Voltage (GND)
Digital output – push-pull
ams Datasheet: 2014-Jun-05 [v1-06]
Pulse Width Modulation output
AS5048A/AS5048B – 5
Absolute Maximum Ratings
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
“Operating Conditions” 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
Unit
Note
Electrical Parameters
VDD5V
DC supply voltage at VDD pin
-0.3
7
V
VDD3V
DC voltage at VDD3V pin
-0.3
5
V
DC voltage at GND pin
-0.3
0.3
V
VDD+0.3
V
100
mA
Norm: Jedec 78
kV
Norm: MIL 883 E method 3015
GND
VIN
Input pin voltage
ISCR
Input current (latchup immunity)
-100
Electroststic Discharge
ESD
Electrostatic discharge
±2
Power Dissipation
PT
Total power dissipation
(all supplies and outputs)
150
mW
Temperature Ranges and Storage Conditions
TSTRG
Storage temperature
TBODY
Package body temperature
H
Humidity non-condensing
MSL
Moisture Sensitive Level
AS5048A/AS5048B – 6
-55
150
5
3
°C
260
°C
85
%
The reflow peak soldering
temperature (body
temperature) specified is in
accordance with IPC/JEDEC
J-STD-020 “Moisture Solid
State Surface Mount Devices”.
The lead finish from Pb-free
leaded packages is matte tin
(100%Sn)
Represents a maximum floor
life time of 168h
ams Datasheet: 2014-Jun-05 [v1-06]
Electrical Characteristics
All in this specification defined tolerances for external
components need to be assured over the whole operation
conditions range and also over lifetime.
Electrical Characteristics
Operating Conditions
Figure 8:
Operating Conditions
Symbol
VDD5V
Parameter
Positive supply voltage
VDD3V
VDDCORE
Positive core supply voltage
TAMB
Ambient temperature
ISUP
Supply Current
Min
Max
Unit
Note
4.5
5.5
V
5V Operation via LDO
3
3.6
V
LDO output voltage
3
3.6
V
-40
150
°C
15
mA
Only for 5V operation.
T_amb_max for 3V is 125°C
DC/AC Characteristics for Digital Inputs and
Outputs
Figure 9:
DC/AC Characteristics
Symbol
Parameter
Min
Max
Unit
CMOS Digital Input with Schmitt Trigger: CSn, CLK, MOSI and SCL, A1, A2
VIH
High level input voltage
VIL
Low level input voltage
lLEAK
0.7 * VDDCORE
Input leakage current
V
0.3 * VDDCORE
V
1
μA
CMOS Output: PWM, MISO, SDA
VOH
High level output voltage
VOL
Low level output voltage
CL
IOUT
VDDCORE - 0.5
V
GND+0.4
V
Capacitive load
50
pF
Output current
4
mA
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 7
Electrical Characteristics
Electrical System Specifications
VDD5V = 5V, T Ambient = -40 to +150°C unless noted otherwise.
Figure 10:
System Specification
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Bz
Magnetic input field
30
50
70
mT
fsample
Output sampling rate
10.2
11.25
12.4
kHz
RES
Output Resolution
14
Noise
Sensor output noise
tprop
System propagation delay
90.7
fPWM
PWM frequency
0.907
INLOPT
@25ºC
INL
OPT+TEMP
INL
DIS+TEMP
tstartup
0.06
Deg
100
110.2
μs
1
1.102
kHz
Non-linearity, optimum
placement of the magnet
± 0.8
Deg
Non-linearity optimum
placement of the magnet
over the full Temperature
Range
±1
Deg
±1.2
Deg
10
ms
Non-linearity @
displacement of magnet
and temperature -40ºC to
150ºC
Startup Time
AS5048A/AS5048B – 8
[email protected], rms value
Bit
Assuming N35H Magnet
(D=8mm, H=3mm) 500um
displacement in x and y
z-distance @ 2000um
ams Datasheet: 2014-Jun-05 [v1-06]
Fu n c t i o n a l D e s c r i p t i o n
Functional Description
The AS5048 is a magnetic Hall sensor system manufactured in
a CMOS process. A lateral Hall sensor array is used to measure
the magnetic field components perpendicular to the surface of
the chip. The AS5048 is uses self-calibration methods to
eliminate signal offset and sensitivity drifts.
The integrated Hall sensors are placed around the center of the
device and deliver a voltage representation of the magnetic flux Bz.
Through Sigma-Delta Analog-to-Digital Converter (ADC) and
Digital Signal-Processing (DSP) algorithms, the AS5048
provides accurate high-resolution absolute angular position
information. This is executed by a Coordinate Rotation Digital
Computer (CORDIC) which calculates the angle and the
magnitude of the Hall array signals.
The DSP is also used to provide digital information at the
outputs that indicate movements of the magnet towards or
away from the device’s surface, in the z-axis.
A small diametrically magnetized (two-pole) standard magnet
provides the angular position information. Depending on the
system requirements different magnet diameters are possible.
Additional flexibility is given by the wide range of the magnetic
input range. The AS5048 can be combined with NeFeB, SmCo
and alternative magnet materials e.g. hard ferrites. The AS5048
provides a 14-bit binary code representing the angular position
of the magnet. The type of output is pre-programmed as SPI
version A or I²C version B. Simultaneously a PWM output signal
is available in 12 bit format.
A simple programming of the zero position is possible over the
interface. No additional programmer is needed. The AS5048
uses one time programmable (OTP) fuses for permanent
programming of the user settings. The verification is possible
over a simple digital readout of the OTP content.
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 9
Operation
Operation
Supply Voltage Configuration
The AS5048 operates at 5V ±10%, using an internal
Low-Dropout (LDO) voltage regulator. In addition a 3.3V
operation is possible. The VDD3V output is intended for
internal use only. It must not be loaded with an external load.
Figure 11:
Connections for 5V and 3.3V Supply Voltages
3.3V Operation
5V Operation
10µF
VDD3V
VDD3V
100nF
10µF
100nF
LDO
LDO
VDD5V
VDD5V
Internal
VDD3.3V
Internal
VDD3.3V
4.5 - 5.5V
3.0 - 3.6V
GND
GND
Note(s) and/or Footnote(s):
1. The pin VDD3V must always be buffered by a 10 μF capacitor in 5V operation. It must not be left floating, as this may cause unstable
internal supply voltages which may lead to larger output jitter of the measured angle.
In 3V operation the VDD3V must be shorted to VDD5V. The ambient temperature TAMB is limited to 125°C in this mode.
SPI Interface
The 16 bit SPI Interface enables read / write access to the
register blocks and is compatible to a standard micro controller
interface. The SPI is active as soon as CSn is pulled low. The
AS5048A then reads the digital value on the MOSI (master out
slave in) input with every falling edge of CLK and writes on its
MISO (master in slave out) output with the rising edge. After 16
clock cycles CSn has to be set back to a high status in order to
reset some parts of the interface core.
SPI Interface Signals (4-Wire Mode, Wire_mode = 1)
The AS5048A only supports slave operation mode. Therefore
CLK for the communication as well as the CSn signal has to be
provided by the test equipment. The following picture shows a
basic interconnection diagram with one master and an
AS5048A device and a principle schematic of the interface core.
AS5048A/AS5048B – 10
ams Datasheet: 2014-Jun-05 [v1-06]
Operation
Figure 12:
SPI Connection AS5048A with μC
CLK
SPI_CLK
CSn
SPI_SSN
MOSI
MOSI
Interface Core
RXSR
Master Device
RXSPI
TXSPI
(Tester)
TXSR
MISO
MISO
AS5048A
Because the interface has to decode the sent command before
it can react and provide data the response of the chip to a
specific command applied at a time T can be accessed in the
next transmission cycle ending at T + TCOM. The data are sent
and read with MSB first. Every time the chip is accessed it is
sending and receiving data.
Figure 13:
SPI Command/Response Data Flow
TCOM
MSB
MOSI
MISO
MSB
LSB
MSB
LSB
MSB
LSB
MSB
LSB
Command 1
Command 2
Command 3
Command N
NOP
Response 1
Response 2
Response N-1
LSB
Transmission 1
ams Datasheet: 2014-Jun-05 [v1-06]
MSB
LSB
Transmission 2
MSB
LSB
Transmission 3
MSB
LSB
Transmission N
AS5048A/AS5048B – 11
Operation
SPI Timing
Figure 14:
SPI Timing Diagram
tCSn
CSn
(Input)
tL
tclk
tclkL
tclkH
tH
CLK
(Input)
tMISO
tOZ
MISO
(Output)
data[15]
data[14]
data[0]
tOZ
tMOSI
MOSI
(Input)
data[15]
data[14]
data[0]
Figure 15:
SPI Timing Characteristics
Parameter
tL
Description
Min
Max
Unit
Time between CSn falling edge and CLK rising edge
350
ns
TCLK
Serial clock period
100
ns
tCLKL
Low period of serial clock
50
ns
tCLKH
High period of serial clock
50
ns
Time between last falling edge of CLK and rising edge of CSn
50
ns
TCSnH
High time of CSn between two transmissions
350
ns
tMOSI
Data input valid to clock edge
20
ns
tMISO
CLK edge to data output valid
tH
AS5048A/AS5048B – 12
20
ns
ams Datasheet: 2014-Jun-05 [v1-06]
Operation
SPI Connection to the Host μC
Single Slave Mode
Figure 16:
Single Slave Mode
4 wire mode
µC
MOSI
MOSI
MISO
MISO
SCK
SCK
SS/
SS/
MOSI
AS5048A
0xFFFF
Read angle 1
MISO
0xFFFF
Read angle 2
0xFFFF
Read angle 3
0xFFFF
Read angle 4
Angle 1
Angle 2
Angle 3
SS/
3 wire mode (Read only)
MOSI
µC
1
MISO
MOSI
MISO
MISO
SCK
SCK
SS/
SS/
AS5048A
Angle 1
Angle 2
Angle 3
SS/
Single Slave Mode: This figure shows the SPI connection to the host μC using Single Slave Mode.
3 Wire Mode (read only)
Figure 17:
Multiple Slave, n+3 Wire (Separate ChipSelect)
MOSI
MOSI
MISO
MISO
SCK
SCK
SS1/
SS/
MOSI
µC
AS5048A
1
MISO
SW Reset
0xFFFF
Read angle 1
0xFFFF
Read angle 2
Angle 1
0xFFFF
Read angle 3
Angle 2
Angle 3
SS2/
SS1/
SS3/
MOSI
MISO
SCK
SS2/
SS3/
AS5048A
2
SS/
MOSI
MISO
SCK
AS5048A
3
SS/
Multiple Slave, n+3 Wire (Separate ChipSelect): This figure shows the SPI connection to the host μC using 3
Wire mode.
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 13
Operation
Daisy Chain, 4 Wire
Figure 18:
Daisy Chain, 4 Wire
MOSI
µC
MOSI
MOSI
MISO
MISO
SCK
SCK
SS/
SS/
AS5048A
1
SW Reset
SW Reset
SW Reset
0xFFFF
Read Angle 3
0xFFFF
Read angle 2
0xFFFF
Read Angle 1
MISO
SS/
MOSI
MISO
SCK
MOSI
AS5048A
2
MISO
SS/
0xFFFF
Read angle 3
0xFFFF
Read angle 2
0xFFFF
Read angle 1
Angle 3
Angle 2
Angle 1
SS/
MOSI
MISO
SCK
AS5048A
3
SS/
Daisy Chain, 4 Wire: This figure shows the SPI connection to the host μC using Daisy Chain, 4 wire mode.
SPI Communication Command Package
Every command sent to the AS5048A is represented with the
following layout.
Figure 19:
SPI Command Package
Command Package
Bit
MSB
14
PAR
RWn
13
12
11
10
9
8
7
6
5
4
3
2
1
LSB
Address<13:0>
Bit Definition & Description
PAR
Parity bit (EVEN)
RWn
Indicates read(1) or write(0) command
Address
AS5048A/AS5048B – 14
14 bit address code
ams Datasheet: 2014-Jun-05 [v1-06]
Operation
Read Package (Value Read from AS5048A)
The read frame always contains two alarm bits, the parity and
error flags and the addressed data of the previous read
command.
Figure 20:
SPI Read Package
Read Package
Bit
MSB
14
PAR
EF
13
12
11
10
9
8
7
6
5
4
3
2
1
LSB
Data<13:0>
Bit Definition & Description
PAR
Parity bit (EVEN)
EF
Error flag indicating a transmission error in a previous host transmission
Data
14 bit addressed data
Write Data Package (Value Written to AS5048A)
The write frame is compatible to the read frame and contains
two additional bits, parity flag and R flag.
If the previous command was a write command a second
package has to be transmitted.
Figure 21:
SPI Write Data Package
Data Package
Bit
MSB
14
PAR
R
13
12
11
10
9
8
7
6
5
4
3
2
1
LSB
Data <13:0>
Bit Definition & Description
PAR
R
Data
Parity bit (EVEN)
Has to be 0
14 bit data to write to former selected address
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 15
Register Description
Register Description
Figure 22:
SPI Register Map
Address
hex
Name
Access
Type
Bit
Symbol
Default
Description
Control and Error Registers
13
x0000
NOP
R
:
NOP
0
Not used
n.a.
No operation dummy
information
0
13
:
x0001
Clear Error
Flag
3
Error Register. All errors
are cleared by access
R
2
Parity Error
1
Command Invalid
0
Framing Error
0
13
:
Not used
7
6
Verify
5
x0003
Programming
Control
R/W
Not used
4
3
Burn
2
0
Programming control
register.
Programming must be
enabled before burning
the fuse(s). After
programming is a
verification mandatory.
See programming
procedure.
Reserved
1
0
AS5048A/AS5048B – 16
Programming
Enable
ams Datasheet: 2014-Jun-05 [v1-06]
Register Description
Address
hex
Name
Access
Type
Bit
Symbol
Default
Description
Programmable Customer Settings
13
:
x0016
OTP Register
Zero Position
Hi
R/W
+
Program
Not used
0
8
7
Zero Position <13>
0
:
:
:
0
Zero Position <6>
0
Not used
0
Zero Position value high
byte
13
:
x0017
OTP Register
Zero Position
Low 6 LSBs
R/W
+
Program
6
5
Zero Position <5>
0
:
:
:
0
Zero Position <0>
0
Zero Position remaining
6 lower LSB's
Readout Registers
13
Not used
n.a.
11
Comp High
0
10
Comp Low
0
9
COF
0
8
OCF
1
7
AGC value<7>
1
:
:
:
0
AGC value<0>
0
13
Magnitude<13>
0
:
:
:
0
Magnitude<0>
0
13
Angle <13>
0
:
:
:
0
Angle<0>
0
12
Diagnostics flags
x3FFD
x3FFE
x3FFF
Diagnostics +
Automatic
Gain Control
(AGC)
Magnitude
Angle
ams Datasheet: 2014-Jun-05 [v1-06]
R
R
R
Automatic Gain Control
value.
0 decimal represents
high magnetic field 255
decimal represents low
magnetic field
Magnitude information
after ATAN calculation
Angle information after
ATAN calculation and
zero position adder
AS5048A/AS5048B – 17
SPI Inter face Commands
SPI Interface Commands
READ Command
For a single READ command two transmission sequences are
necessary. The first package written to the AS5048 contains the
READ command (MSB-1 high) and the address the chip has to
access, the second package transmitted to the AS5048 device
can be any command the chip has to process next. The content
of the desired register is available in the MISO register of the
master device at the end of the second transmission cycle.
Figure 23:
READ Command
TCOM
MSB
LSB
MOSI
MISO
MSB
LSB
READ
Next command
Response -1
Response on
READ command
MSB
LSB
MSB
Transmission N
LSB
Transmission N+1
WRITE Command
A single WRITE command takes two transmission cycles. With a
NOP command after the WRITE command you can verify the
sent data with three transmission cycles because the data will
be send back during the following command.
Figure 24:
WRITE Command
TCOM
MSB
LSB
MOSI
MISO
MSB
LSB
MSB
LSB
WRITE
command
DATA
NOP
Response-1
Old register
content
New register
content
MSB
LSB
Transmission N
AS5048A/AS5048B – 18
MSB
LSB
Transmission N+1
MSB
LSB
Transmission N+2
ams Datasheet: 2014-Jun-05 [v1-06]
SPI Inter face Commands
CLEAR ERROR FLAG Command
The CLEAR ERROR FLAG command is implemented as READ
command. This command clears the ERROR FLAG which is
contained in every READ frame. Before the ERROR FLAG is
cleared the error register content comes back with the
information which error type was occurred. On the next new
READ register the ERROR FLAG is cleared.
Figure 25:
CLEAR ERROR FLAG Command
TCOM
MSB
LSB
MSB
LSB
MOSI
CLEAR ERROR
FLAG
Next command
Next command
MISO
Response-1
EF
Error register
Content + EF
New register
EF cleared
MSB
LSB
MSB
Transmission N
MSB
LSB
LSB
Transmission N+2
Transmission N+1
The package necessary to perform a CLEAR ERROR FLAG is built
up as follows.
Figure 26:
Clear Error Flag Command
CLEAR ERROR FLAG Command
Bit
MSB
14
13
12
11
10
9
8
7
6
5
4
3
2
1
LSB
PAR
1
0
0
0
0
0
0
0
0
0
0
0
0
0
1
Possible conditions which force the ERROR FLAG to be set:
• Wrong parity
• Wrong number of clocks (no full transmission cycle or too
many clocks)
• Invalid command
• Frame error
Note(s): If the error flag is set to high because of a
communication problem the flag remains set until it will be
cleared by the CLERAR ERROR FLAG command.
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 19
SPI Inter face Commands
NOP Command
The NOP command represents a dummy write to the AS5048.
Figure 27:
NOP Command
TCOM
MSB
LSB
MOSI
MISO
MSB
LSB
MSB
LSB
NOP
NOP
Next command
Response-1
0x0000
0x0000
MSB
LSB
MSB
Transmission N
LSB
MSB
Transmission N+1
LSB
Transmission N+2
The NOP command frame looks like follows.
Figure 28:
NOP Command
NOP Command
Bit
MSB
14
13
12
11
10
9
8
7
6
5
4
3
2
1
LSB
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
The chip’s response on this command is 0x0000
AS5048A/AS5048B – 20
ams Datasheet: 2014-Jun-05 [v1-06]
I²C Inter face
The AS5048B supports 2-wire high-speed I²C protocol in device
mode. The host MCU (master) has to initiate the data transfers.
The 7-bit device address of the slave depends on the state of
the OTP I²C register 21 (0x15) bit 0…4 + 2 I²C address selection
pin 3 and 4.
I²C Interface
Supported modes:
• Random/Sequential Read
• Byte/Page Write
• Standard : 0 to 100kHz clock frequency (slave mode) • Fast Mode : 0 to 400kHz clock frequency (slave mode)
• High Speed: 0 to 3.4MHz clock frequency (slave mode)
The SDA signal is bidirectional and is used to read and write the
serial data. The SCL signal is the clock generated by the host
MCU, to synchronize the SDA data in read and write mode. The
maximum I²C clock frequency is 3.4MHz, data are triggered on
the rising edge of SCL.
I²C Electrical Specification
Figure 29:
I²C Electrical Specification
FS-mode+
Symbol
Parameter
Condition
HS-mode
CB=100pF
HS-mode
CB=400pF
Min
Max
Min
Max
Min
Max
-0.5
0.3VDDC
-0.5
0.3VDDC
Unit
VIL
LOW-Level Input
Voltage
-0.5
0.3VDDC
VIH
HIGH-Level Input
Voltage
0.7VDD
VDDCORE
+ 0.5
0.7VDD
CORE
VDDCORE
+ 0.5
0.7VDD
CORE
CORE
VDDCORE
+ 0.5
V
Vhys
Hysteresis of Schmitt
Trigger Inputs
VDDCORE< 2V
0.1VDD
--
0.1VDD
--
0.1VDD
--
V
VOL
LOW-Level Output
Voltage (open-drain
or open-collector) at
3mA Sink Current
VDDCORE< 2V
--
0.2VDDC
--
0.2VDDC
--
0.2VDDC
V
IOL
LOW-Level Output
Current
VOL = 0.4V
20
--
--
--
--
mA
ICS
Pull-up current of
SCLH current source
--
--
3
12
3
12
mA
tSP
Pulse Width of Spikes
that must be
suppressed by the
Input Filter
--
50 (1)
--
10
--
10
ns
ams Datasheet: 2014-Jun-05 [v1-06]
CORE
ORE
ORE
CORE
ORE
ORE
CORE
ORE
ORE
V
AS5048A/AS5048B – 21
I²C Inter face
HS-mode
CB=100pF
FS-mode+
Symbol
Parameter
Condition
Input
Voltage
between
HS-mode
CB=400pF
Unit
Min
Max
Min
Max
Min
Max
-10
+10 (2)
--
10
--
10
μA
Ii
Input Current at each
I/O Pin
CB
Total Capacitive Load
for each Bus Line
--
550
--
100
--
400
pF
CI/O
I/O Capacitance
(SDA,SCL)
--
10
--
10
--
10
pF
Note(s) and/or Footnote(s):
1. Input filters on the SDA and SCL inputs suppress noise spikes of less than 50 ns.
2. I/O pins of Fast-mode and Fast-mode Plus devices must not obstruct the SDA and SCL lines if VDD is switched off.
I²C Timing
Figure 30:
I²C Timing
FS-mode+
Symbol
Parameter
Condition
HS-mode
CB=100pF
HS-mode
CB=400pF (5)
Unit
Min
Max
Min
Max
Min
Max
--
1000
--
3400
--
1700
kHz
fSCLK
SCL clock
Frequency
tBUF
Bus Free Time; time
between STOP and
START Condition
500
--
500
--
500
--
ns
tHD;STA
Hold Time;
(Repeated) START
Condition (1)
260
--
160
--
160
--
ns
tLOW
LOW Period of SCL
Clock
500
--
160
--
320
--
ns
tHIGH
HIGH Period of SCL
Clock
260
--
60
--
120
--
ns
tSU;STA
Setup Time for a
Repeated START
condition
260
--
160
--
160
--
ns
tHD;DAT
Data Hold Time (2)
0
450
0
70
0
150
ns
tSU;DAT
Data Setup Time (3)
50
--
10
--
10
--
ns
20+0.1Cb
120
--
--
--
--
ns
tR
Rise Time of SDA
and SCL Signals
AS5048A/AS5048B – 22
ams Datasheet: 2014-Jun-05 [v1-06]
I²C Inter face
FS-mode+
Symbol
tF
Parameter
Condition
Fall time of SDA and
SCL signals
HS-mode
CB=100pF
HS-mode
CB=400pF (5)
Unit
Min
Max
Min
Max
Min
Max
20+0.1Cb
120 (4)
--
--
--
--
ns
trCL
Rise time of SCLH
signal
Ext. pull-up
source of
3mA
--
--
10
40
20
80
ns
trCL1
Rise time of SCLH
Ext. pull-up
signal after
source of
repeated START
condition and after 3mA
an acknowledge bit
--
--
10
80
20
160
ns
tfCL
Output rise time of
SCLH signal
Ext. pull-up
source of
3mA
--
--
10
40
20
80
ns
trDA
Output rise time of
SDAH signal
--
--
10
80
20
160
ns
tfDA
Output rise time of
SDAH signal
--
--
10
80
20
160
ns
tSU;STO
Setup Time for
STOP Condition
260
--
160
--
160
--
ns
VnL
Noise margin at
LOW level
0.1VDDp
--
0.1VDDp
--
0.1VDDp
--
V
VnH
Noise margin at
HIGH level
0.2VDDp
--
0.2VDDp
--
0.2VDDp
--
V
Note(s) and/or Footnote(s):
1. After this time the first clock is generated.
2. A device must internally provide a minimum hold time (120ns / max 250ns for Fast-mode Plus, 80ns / max 150ns for High-speed
mode) for the SDA signal (referred to the VIHmin of the SCL) to bridge the undefined region of the falling edge of SCL.
3. A fast-mode device can be used in standard-mode system, but the requirement tSU;DAT = 250ns must then e met. This is automatically
the case if the device does not stretch the LOW period of the SCL signal. If such a device does stretch the LOW period of the SCL
signal, it must output the next data bit to the SDA line t Rmax + TSU;DAT = 1000 + 250 = 1250ns before the SCL line is released.
4. In Fast-mode Plus, fall time is specified the same for both output stage and bus timing. If series resistors are used this has to be
considered for bus timing.
5. For capacitive bus loads between 100pF and 400pF, the timing parameters must be linearly interpolated
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 23
I²C Inter face
Register Table
The following registers / functions are accessible over the serial
I²C interface.
Figure 31:
Register Map I²C
Address
hex
Name
Access
Type
Bit
Symbol
Default
Description
0
Programming control
register. Programming
must be enabled before
burning the fuse(s). After
programming is an
verification mandatory.
See programming
procedure.
Control OTP
7
Not used
6
Verify
5
Not used
4
x03
Programming
Control
R/W
3
Burn
2
Reserved
1
0
Programming
Enable
Programmable Customer Settings
7
:
Not used
n.a.
4
I²C address<4>
internally
inverted
:
:
:
0
I²C address<0>
0
7
Zero Position <13>
0
:
:
:
0
Zero Position <6>
0
Not used
n.a.
5
Zero Position <5>
0
:
:
:
0
Zero Position <0>
0
5
x15
x16
I²C slave
address
OTP Register
Zero Position
Hi
R/W
R/W
+
Program
I²C slave address slave
address consist of 5 bits
(MSBs) and the hardware
setting of Pins A1 and A2
I²C address <4> is the
inversion defined as '1'
Zero Position value high
byte
7
6
x17
OTP Register
Zero Position
Low 6 LSBs
AS5048A/AS5048B – 24
R/W
+
Program
Zero Position remaining
6 lower LSB's
ams Datasheet: 2014-Jun-05 [v1-06]
I²C Inter face
Address
hex
Name
Access
Type
Bit
Symbol
Default
Description
Readout Registers
xFA
Automatic
Gain
Control
R
7
AGC value<7>
1
:
:
:
0
AGC value<0>
0
Not used
n.a.
3
Comp High
0
2
Comp Low
0
1
COF
0
0
OCF
1
7
Magnitude<13>
0
:
:
:
0
Magnitude<6>
0
Not used
n.a.
5
Magnitude<5>
0
:
:
:
0
Magnitude<0>
0
7
Angle<13>
0
:
:
:
0
Angle<6>
0
Not used
n.a.
5
Angle<5>
0
:
:
:
0
Angle<0>
0
Automatic Gain Control
value.
0 decimal represents
high magnetic field 255
decimal represents low
magnetic field
7
:
4
xFB
Diagnostics
xFC
R
R
7
Magnitude
6
xFD
R
xFE
R
7
Angle
6
xFF
ams Datasheet: 2014-Jun-05 [v1-06]
R
Diagnostic flags
Magnitude information
afer ATAN calculation
Angle Value afer ATAN
calculation and zero
position adder
AS5048A/AS5048B – 25
I²C Inter face
I²C Slave address
Data Byte (n)
Stop
Slave Address
A A
2 1
X X X X X X X X
Slave Address
Register Address
X X X X X X X X
Data Byte (n)
LSB
Start
1 0 0 0 0
ACK
random write
X X X X X X X X
HW
Pins
R/W
ACK
OTP cotent
(Default)
A A
2 1
LSB
Register Address
LSB
Slave Address
1 0 0 0 0
X X X X X X X X
R/W
ACK
A A
2 1
ACK
Stop
Start
1 0 0 0 0
HW
Pins
ACK
Start
random read
HW
Pins
R/W
ACK
OTP cotent
(Default)
ACK
Figure 32:
Slave Address Construction
Note(s) and/or Footnote(s):
1. It's important to use a STOP condition only after a complete read or write sequence.
The slave address consists of the hardware setting on pins A1,
A2. The MSB of the slave address (yellow) is internally inverted.
This means that by default the resulting data is ‘1’. A read of the
I²C slave address register 21 will return a ‘0’ at the MSB.
AS5048A/AS5048B – 26
ams Datasheet: 2014-Jun-05 [v1-06]
PWM Inter face
The AS5048 provides a pulse width modulated output (PWM),
whose duty cycle is proportional to the measured angle. The
PWM frequency is internally trimmed to an accuracy of ±10%
over full temperature range. This tolerance can be cancelled by
measuring the complete duty cycle.
PWM Interface
The PWM signal consists of different sections:
• Init:
12 clocks
→ PWM = ‘high’
• Error_n:
4 clocks
→ PWM = ‘not(system_error)’
• Data:
4095 clocks
→ PWM = ‘angle_zero’ / ‘low’
(in case of error)
• Exit:
8 clocks
→ PWM = ‘low’
In case of an error the data section is set to zero.
Figure 33:
PWM Format
Init
Error_n
Data
4095 clocks
Zero degree
16 clocks
Exit
8 clocks
Figure 34:
PWM Period and resolution
Parameter
Symbol
Value
Unit
PWM Frequency
F_PWM
1
KHz
PWM Pulse period
T_PWM
4119
bit
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 27
Application Information
Application Information
Programming of the AS5048
Programming of the Zero Position: The absolute angle
position can be permanent programmed over the interface.
This could be useful for random placement of the magnet on
the rotation axis. A readout at the mechanical zero position can
be performed and written back into the IC. With permanent
programming the position is non-reversible stored in the IC.
This programming can be performed only once.
To simplify the calculation of the zero position it is only needed
to write the value in the IC which was read out before from the
angle register.
Programming Sequence with Verification: To program the
zero position is needed to perform following sequence:
1. Write 0 into OTP zero position register to clear
2. Read angle information
3. Write previous read angle position into OTP zero
position register
Now the zero position is set.
If you want to burn it to the OTP register send:
4. Set the Programming Enable bit in the OTP control
register
5. Set the Burn bit to start the automatic programming
procedure
6. Read angle information (equals to 0)
7. Set the Verify bit to load the OTP data again into the
internal registers
8. Read angle information (equals to 0)
The programming can either be performed in 5V operation
using the internal LDO, or in 3V operation but using a minimum
supply voltage of 3.3V. In case of 3V operation, also a 10μF
capacitor is required on the VDD3 pin.
Programming the I²C Slave address: For informations of
programming the I²C Slave address please refer to our
application note covering this topic.
AS5048A/AS5048B – 28
ams Datasheet: 2014-Jun-05 [v1-06]
Application Information
Diagnostic Functions of the AS5048
The AS5048 provides diagnostics functions of the IC and also
diagnostic functions of the magnetic input field
Following diagnostic flags are available:
See Figure 22 register address x3FFD (AS5048A) or Figure 31
register address 251 dec (AS5048B)
• OCF (Offset Compensation Finished), logic high indicates
the finished Offset Compensation Algorithm. After power
up the flag remains always to logic high.
• COF (Cordic Overflow), logic high indicates an out of
range error in the CORDIC part. When this bit is set, the
angle and magnitude data is invalid. The absolute output
maintains the last valid angular value.
• COMP low, indicates a high magnetic field. It is
recommended to monitor in addition the magnitude
value.
• COMP high, indicated a weak magnetic field. It is
recommended to monitor the magnitude value.
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 29
Application Information
Choosing the Proper Magnet
The AS5048 works with a variety of different magnets in size
and shape. A typical magnet could be 6-8 mm in diameter and
≥2.5mm in height The magnetic field strength perpendicular to
the die surface has to be in the range of ±30mT … ±70mT (peak).
The magnet’s field strength should be verified using a
gauss-meter. The magnetic flux B Z at a given distance, along a
concentric circle with a radius of 1.1mm (R1), should be in the
range of ±30mT…±70mT.
Figure 35:
Typical Magnet and Magnetic Flux Distribution
typ. 6-8mm diameter
N
S
Magnet axis
R1
Magnet axis
Vertical field
component
N
S
R1 concentric circle;
radius 1.1mm
Vertical field
component
Bv
(30…70mT)
0
AS5048A/AS5048B – 30
360
ams Datasheet: 2014-Jun-05 [v1-06]
Application Information
Physical Placement of the Magnet
The best linearity can be achieved by placing the center of the
magnet exactly over the defined center of the chip as shown in
the drawing below:
Figure 36:
Defined Chip Center and Magnet Displacement Radius
3.2 mm
3.2 mm
1
2.5 mm
Defined
center
Rd
2.5 mm
Area of recommended maximum
magnet misalignment
Magnet Placement
The magnet’s center axis should be aligned within a
displacement radius R d of 0.25 mm (larger magnets allow more
displacement e.g. 0.5 mm) from the defined center of the IC.
The magnet may be placed below or above the device. The
distance should be chosen such that the magnetic field on the
die surface is within the specified limits The typical distance “z”
between the magnet and the package surface is 0.5mm to
2.5mm, provided the use of the recommended magnet material
and dimensions (6mm x 3mm). Larger distances are possible, as
long as the required magnetic field strength stays within the
defined limits.
However, a magnetic field outside the specified range may still
produce usable results, but the out-of-range condition will be
indicated by indication flags.
Figure 37:
Vertical Placement of the Magnet
S
N
Package surface
Die surface
0.2299±0.100
0.2341±0.100
0.7701±0.150
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 31
Pack age Drawings & Mark ings
Package Drawings & Markings
Package type: TSSOP14
Figure 38:
Package Markings for AS5048A & AS5048B
Figure 39:
Package Code YYWWMZZ
YY
Last two digits of the year
AS5048A/AS5048B – 32
WW
Manufacturing week
M
Plant identifier
ZZ
Letters for free traceability
ams Datasheet: 2014-Jun-05 [v1-06]
Pa c k a g e D r a w i n g s & M a r k i n g s
Figure 40:
14-Lead Thin Shrink Small Outline Package TSSOP-14
Symbol
Min
Nom
Max
Symbol
Min
Nom
Max
A
-
-
1.20
R
0.09
-
-
A1
0.05
-
0.15
R1
0.09
-
-
A2
0.80
1.00
1.05
S
0.20
-
-
b
0.19
-
0.30
θ1
0º
-
8º
c
0.09
-
0.20
θ2
-
12 REF
-
D
4.90
5.00
5.10
θ3
-
12 REF
-
E
-
6.40 BSC
-
aaa
-
0.10
-
E1
4.30
4.40
4.50
bbb
-
0.10
-
e
-
0.65 BSC
-
ccc
-
0.05
-
L
0.45
0.60
0.75
ddd
-
0.20
-
L1
-
1.00 REF
-
N
14
Note(s) and/or Footnote(s):
1. Dimensioning & toleranceing confirm to ASME Y14.5M-1994.
2. All dimensions are in millimeters. Angles are in degrees.
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 33
Ordering & Contact Information
Ordering & Contact Information
The devices are available as standard products.
Figure 41:
Ordering Information
Ordering Code
Description
Delivery Form
Package
AS5048A-HTSP
14 –Bit Programmable Magnetic Rotary Encoder
with SPI-Interface
Tape & Reel
TSSOP 14
AS5048B-HTSP
14 –Bit Programmable Magnetic Rotary Encoder
with I²C-Interface
Tape & Reel
TSSOP 14
Buy our products or get free samples online at:
www.ams.com/ICdirect
Technical Support is available at:
www.ams.com/Technical-Support
For further information and requests, e-mail us at:
[email protected]
For sales offices, distributors and representatives, please visit:
www.ams.com/contact
Headquarters
ams AG
Tobelbaderstrasse 30
8141 Unterpremstaetten
Austria, Europe
Tel: +43 (0) 3136 500 0
Website: www.ams.com
AS5048A/AS5048B – 34
ams Datasheet: 2014-Jun-05 [v1-06]
RoHS Compliant & ams Green Statement
RoHS Compliant & ams Green
Statement
RoHS: The term RoHS compliant means that ams AG products
fully comply with current RoHS directives. Our semiconductor
products do not contain any chemicals for all 6 substance
categories, including the requirement that lead not exceed
0.1% by weight in homogeneous materials. Where designed to
be soldered at high temperatures, RoHS compliant products are
suitable for use in specified lead-free processes.
ams Green (RoHS compliant and no Sb/Br): ams Green
defines that in addition to RoHS compliance, our products are
free of Bromine (Br) and Antimony (Sb) based flame retardants
(Br or Sb do not exceed 0.1% by weight in homogeneous
material).
Important Information: The information provided in this
statement represents ams AG knowledge and belief as of the
date that it is provided. ams AG bases its knowledge and belief
on information provided by third parties, and makes no
representation or warranty as to the accuracy of such
information. Efforts are underway to better integrate
information from third parties. ams AG has taken and continues
to take reasonable steps to provide representative and accurate
information but may not have conducted destructive testing or
chemical analysis on incoming materials and chemicals. ams AG
and ams AG suppliers consider certain information to be
proprietary, and thus CAS numbers and other limited
information may not be available for release.
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 35
Copyrights & Disclaimer
Copyrights & Disclaimer
Copyright ams AG, Tobelbader Strasse 30, 8141
Unterpremstaetten, Austria-Europe. Trademarks Registered. All
rights reserved. The material herein may not be reproduced,
adapted, merged, translated, stored, or used without the prior
written consent of the copyright owner.
Devices sold by ams AG are covered by the warranty and patent
indemnification provisions appearing in its General Terms of
Trade. ams AG makes no warranty, express, statutory, implied,
or by description regarding the information set forth herein.
ams AG reserves the right to change specifications and prices
at any time and without notice. Therefore, prior to designing
this product into a system, it is necessary to check with ams AG
for current information. This product is intended for use in
commercial applications. Applications requiring extended
temperature range, unusual environmental requirements, or
high reliability applications, such as military, medical
life-support or life-sustaining equipment are specifically not
recommended without additional processing by ams AG for
each application. This product is provided by ams AG “AS IS”
and any express or implied warranties, including, but not
limited to the implied warranties of merchantability and fitness
for a particular purpose are disclaimed.
ams AG shall not be liable to recipient or any third party for any
damages, including but not limited to personal injury, property
damage, loss of profits, loss of use, interruption of business or
indirect, special, incidental or consequential damages, of any
kind, in connection with or arising out of the furnishing,
performance or use of the technical data herein. No obligation
or liability to recipient or any third party shall arise or flow out
of ams AG rendering of technical or other services.
AS5048A/AS5048B – 36
ams Datasheet: 2014-Jun-05 [v1-06]
Document Status
Document Status
Document Status
Product Preview
Preliminary Datasheet
Datasheet
Datasheet (discontinued)
Product Status
Definition
Pre-Development
Information in this datasheet is based on product ideas in
the planning phase of development. All specifications are
design goals without any warranty and are subject to
change without notice
Pre-Production
Information in this datasheet is based on products in the
design, validation or qualification phase of development.
The performance and parameters shown in this document
are preliminary without any warranty and are subject to
change without notice
Production
Information in this datasheet is based on products in
ramp-up to full production or full production which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade
Discontinued
Information in this datasheet is based on products which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade, but these products have been superseded and
should not be used for new designs
ams Datasheet: 2014-Jun-05 [v1-06]
AS5048A/AS5048B – 37
Revision Information
Revision Information
Changes from 1-05 (2014-May-20) to current revision 1-06 (2014-Jun-05)
Updated Figure 31
Page(1)
24
Note(s) and/or Footnote(s):
1. Page numbers for the previous version may differ from page numbers in the current revision
AS5048A/AS5048B – 38
ams Datasheet: 2014-Jun-05 [v1-06]
Content Guide
Content Guide
ams Datasheet: 2014-Jun-05 [v1-06]
1
1
2
2
General Description
Key Benefits & Features
Applications
Block Diagram
4
6
Pin Assignment
Absolute Maximum Ratings
7
7
7
8
Electrical Characteristics
Operating Conditions
DC/AC Characteristics for Digital Inputs and Outputs
Electrical System Specifications
9
Functional Description
10
10
10
10
12
13
13
13
14
14
15
15
Operation
Supply Voltage Configuration
SPI Interface
SPI Interface Signals (4-Wire Mode, Wire_mode = 1)
SPI Timing
SPI Connection to the Host μC
Single Slave Mode
3 Wire Mode (read only)
Daisy Chain, 4 Wire
SPI Communication Command Package
Read Package (Value Read from AS5048A)
Write Data Package (Value Written to AS5048A)
16
Register Description
18
18
18
19
20
SPI Interface Commands
READ Command
WRITE Command
CLEAR ERROR FLAG Command
NOP Command
21
21
22
24
26
I²C Interface
I²C Electrical Specification
I²C Timing
Register Table
I²C Slave address
27
PWM Interface
AS5048A/AS5048B – 39
Content Guide
AS5048A/AS5048B – 40
28
28
29
30
31
31
Application Information
Programming of the AS5048
Diagnostic Functions of the AS5048
Choosing the Proper Magnet
Physical Placement of the Magnet
Magnet Placement
32
34
35
36
37
38
Package Drawings & Markings
Ordering & Contact Information
RoHS Compliant & ams Green Statement
Copyrights & Disclaimer
Document Status
Revision Information
ams Datasheet: 2014-Jun-05 [v1-06]