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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
AS5045 12 BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
DATA SHEET
1
General Description
1.2
-
Key Features
Contactless high resolution rotational position encoding over a full turn of 360 degrees Two digital 12bit absolute outputs: - Serial interface and - Pulse width modulated (PWM) output User programmable zero position Failure detection mode for magnet placement monitoring and loss of power supply "red-yellow-green" indicators display placement of magnet in Z-axis Serial read-out of multiple interconnected AS5045 devices using Daisy Chain mode Tolerant to magnet misalignment and airgap variations Wide temperature range: - 40C to + 125C Small Pb-free package: SSOP 16 (5.3mm x 6.2mm)
The AS5045 is a contactless magnetic rotary encoder for accurate angular measurement over a full turn of 360. 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 magnet may be placed above or below the IC. The absolute angle measurement provides instant indication of the magnet's angular position with a resolution of 0.0879 = 4096 positions per revolution. This digital data is available as a serial bit stream and as a PWM signal. An internal voltage regulator allows the AS5045 to operate at either 3.3 V or 5 V supplies
-
1.3
-
Applications
Industrial applications: - Contactless rotary position sensing - Robotics Automotive applications: - Steering wheel position sensing - Transmission gearbox encoder - Headlight position control - Torque sensing - Valve position sensing Replacement of high end potentiometers
-
-
Figure 1: Typical arrangement of AS5045 and magnet
1.1
-
Benefits
Complete system-on-chip Flexible system solution provides absolute and PWM outputs simultaneously Ideal for applications in harsh environments due to contactless position sensing No calibration required
This product is covered by one or more pending European and U.S. patents
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
2
Pin Configuration
MagINCn MagDECn NC NC NC Mode VSS Prog_DI
Pin
16 15
VDD5V VDD3V3 NC NC PWM CSn CLK DO
15 12 13 14 11 10
Symbol
CLK
Type
DI, ST DI_PU, ST DO S S
Description
Clock Input of Synchronous Serial Interface; Schmitt-Trigger input Chip Select, active low; SchmittTrigger input, internal pull-up resistor (~50k) Pulse Width Modulation of approx. 1kHz; LSB in Mode3.x Must be left unconnected Must be left unconnected 3V-Regulator Output, internally regulated from VDD5V. Connect to VDD5V for 3V supply voltage. Do not load externally. Positive Supply Voltage, 3.0 to 5.5 V
1 2 3 4 5 6 7 8
AS5045
14 13 12 11 10 9
CSn PWM NC NC VDD3V3 VDD5V
Figure 2: Pin configuration SSOP16
16
Table 1: Pin description SSOP16
2.1
Pin Description
Table 1 shows the description of each pin of the standard SSOP16 package (Shrink Small Outline Package, 16 leads, body size: 5.3mm x 6.2mmm; see Figure 2). Pins 7, 15 and 16 are supply pins, pins 3, 4, 5, 6, 13 and 14 are for internal use and must not be connected. Pins 1 and 2 are the magnetic field change indicators, MagINCn and MagDECn (magnetic field strength increase or decrease through variation of the distance between the magnet and the device). These outputs can be used to detect the valid magnetic field range. Furthermore those indicators can also be used for contact-less push-button functionality. Pin 6 Mode allows switching between filtered (slow) and unfiltered (fast mode). See section 4
DO_OD DO DI_PD DI_PU
digital digital digital digital
output open drain output input pull-down input pull-up
S DI DO_T ST
supply pin digital input digital output /tri-state Schmitt-Trigger input
Pin 8 (Prog) is used to program the zero-position into the OTP (see chapter 8.1). This pin is also used as digital input to shift serial data through the device in Daisy Chain configuration, (see page 6). Pin 11 Chip Select (CSn; active low) selects a device within a network of AS5045 encoders and initiates serial data transfer. A logic high at CSn puts the data output pin (DO) to tri-state and terminates serial data transfer. This pin is also used for alignment mode (Figure 12) and programming mode (Figure 9). Pin 12 allows a single wire output of the 10-bit absolute position value. The value is encoded into a pulse width modulated signal with 1s pulse width per step (1s to 4096s over a full turn). By using an external low pass filter, the digital PWM signal is converted into an analog voltage, making a direct replacement of potentiometers possible.
Pin
1
Symbol
MagINCn
Type
DO_OD
Description
Magnet Field Magnitude INCrease; active low, indicates a distance reduction between the magnet and the device surface. See Table 5 Magnet Field Magnitude DECrease; active low, indicates a distance increase between the device and the magnet. See Table 5 Must be left unconnected Must be left unconnected Must be left unconnected Select between slow (open, low: VSS) and fast (high) mode. Internal pull-down resistor. Negative Supply Voltage (GND) OTP Programming Input and Data Input for Daisy Chain mode. Internal pull-down resistor (~74k). Connect to VSS if not used Data Output of Synchronous Serial Interface
2 3 4 5 6 7 8
MagDECn NC NC NC Mode VSS Prog_DI
DO_OD S DI_PD
3
Functional Description
The AS5045 is manufactured in a CMOS standard process and uses a spinning current Hall technology for sensing the magnetic field distribution across the surface of the chip. The integrated Hall elements are placed around the center of the device and deliver a voltage representation of the magnetic field at the surface of the IC. Through Sigma-Delta Analog / Digital Conversion and Digital Signal-Processing (DSP) algorithms, the AS5045 provides accurate high-resolution absolute angular
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9
DO
DO_T
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
position information. For this purpose a Coordinate Rotation Digital Computer (CORDIC) calculates the angle and the magnitude of the Hall array signals. The DSP is also used to provide digital information at the outputs M a g I N C n and M a g D E C n that indicate movements of the used magnet towards or away from the device's surface. A small low cost diametrically magnetized (two-pole) standard magnet provides the angular position information (see Figure 15).
The AS5045 senses the orientation of the magnetic field and calculates a 12-bit binary code. This code can be accessed via a Synchronous Serial Interface (SSI). In addition, an absolute angular representation is given by a Pulse Width Modulated signal at pin 12 (PWM). This PWM signal output also allows the generation of a direct proportional analogue voltage, by using an external LowPass-Filter. The AS5045 is tolerant to magnet misalignment and magnetic stray fields due to differential measurement technique and Hall sensor conditioning circuitry.
Figure 3: AS5045 block diagram
4
Mode Input Pin
The mode input pin activates or deactivates an internal filter, that is used to reduce the analog output noise. Activating the filter (Mode pin = LOW or open) provides a reduced output noise of 0.03 rms. At the same time, the output delay is increased to 384s. This mode is recommended for high precision, low speed applications. Deactivating the filter (Mode pin = HIGH) reduces the output delay to 96s and provides an output noise of 0.06 rms. This mode is recommended for higher speed applications. Switching the Mode pin affects the following parameters: Parameter sampling rate transition noise (1 sigma) output delay max. speed @ 4096 samples/sec. max. speed @ 1024 samples/sec. max. speed @ 256 samples/sec. slow mode (Mode = low or open) 2.61 kHz (384 s) 0.03 rms 384s 38 rpm 153 rpm 610 rpm
Table 2: Slow and fast mode parameters
fast mode (Mode = high, VDD5V) 10.42 kHz (96s) 0.06 rms 96s 153 rpm 610 rpm 2442 rpm
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
5
5.1
CSn
12-bit Absolute Angular Position Output
Synchronous Serial Interface (SSI)
tCLK FE TCLK/2 1 8 18
tCLK FE
tCSn 1
CLK
DO
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
OCF
COF
LIN
Mag INC
Mag DEC
Even PAR
D11
tDO active
tDO valid Angular Position Data Status Bits
tDO Tristate
Figure 4: Synchronous serial interface with absolute angular position data
If CSn changes to logic low, Data Out (DO) will change from high impedance (tri-state) to logic high and the read-out will be initiated. After a minimum time tCLK FE, data is latched into the output shift register with the first falling edge of CLK. Each subsequent rising CLK edge shifts out one bit of data. The serial word contains 18 bits, the first 12 bits are the angular information D[11:0], the subsequent 6 bits contain system information, about the validity of data such as OCF, COF, LIN, Parity and Magnetic Field status (increase/decrease) . A subsequent measurement is initiated by a "high" pulse at CSn with a minimum duration of tCSn.
5.1.1
Data Content
D11:D0 absolute angular position data (MSB is clocked out first) OCF (Offset Compensation Finished), logic high indicates the finished Offset Compensation Algorithm COF (Cordic Overflow), logic high indicates an out of range error in the CORDIC part. When this bit is set, the data at D9:D0 is invalid. The absolute output maintains the last valid angular value. This alarm may be resolved by bringing the magnet within the X-Y-Z tolerance limits. LIN (Linearity Alarm), logic high indicates that the input field generates a critical output linearity. When this bit is set, the data at D9:D0 may still be used, but can contain invalid data. This warning may be resolved by bringing the magnet within the X-Y-Z tolerance limits.
Even Parity bit for transmission error detection of bits 1...17 (D11...D0, OCF, COF, LIN, MagINC, MagDEC)
Placing the magnet above the chip, angular values increase in clockwise direction by default. Data D11:D0 is valid, when the status bits have the following configurations: OCF COF LIN Mag INC 0 1 0 0 0 1 1*) Mag DEC 0 1 0 1*) even checksum of bits 1:15 Parity
Table 3: Status bit outputs
*) MagInc=MagDec=1 is only recommended in YELLOW mode (see Table 5)
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
5.1.2
Z-axis Range Indication (Push Button Feature, Red/Yellow/Green Indicator) serial data stream (see Figure 4). Additionally, an OTP programming option is available with bit MagCompEn (see Figure 9) that enables additional features:
The AS5045 provides several options of detecting movement and distance of the magnet in the Z-direction. Signal indicators MagINCn and MagDECn are available both as hardware pins (pins #1 and 2) and as status bits in the In the default state, the status bits MagINC, MagDec and pins MagINCn, MagDECn have the following function: Status bits Mag INC 0 0 1 1 Mag DEC 0 1 0 1 Hardware pins Mag INCn Off Off On On Mag DECn Off On Off On
OTP: Mag CompEn = 0 (default) Description No distance change Magnetic input field OK (in range, ~45...75mT) Distance increase; pull-function. This state is dynamic and only active while the magnet is moving away from the chip. Distance decrease; push- function. This state is dynamic and only active while the magnet is moving towards the chip. Magnetic input field invalid - out of recommended range: too large, too small (missing magnet)
Table 4: Magnetic field strength variation indicator
When bit MagCompEn is programmed in the OTP, the function of status bits MagINC, MagDec and pins MagINCn, MagDECn is changed to the following function: Status bits Mag INC 0 1 1 Mag DEC 0 1 1 LIN 0 0 1 Hardware pins Mag INCn Off On On n/a Mag DECn Off Off On n/a OTP: Mag CompEn = 1 (red-yellow-green programming option) Description No distance change Magnetic input field OK ( GREEN range, ~45...75mT) YELLOW range: magnetic field is ~ 25...45mT or ~75...135mT. The AS5045 may still be operated in this range, but with slightly reduced accuracy. RED range: magnetic field is ~<25mT or >~135mT. It is still possible to operate the AS5045 in the red range, but not recommended. Not available
All other combinations
Table 5: Magnetic field strength red-yellow-green indicator (OTP option)
Note: Pin 1 (MagINCn) and pin 2 (MagDECn) are active low via open drain output and require an external pull-up resistor. If the magnetic field is in range, both outputs are turned off. The two pins may also be combined with a single pull-up resistor. In this case, the signal is high when the magnetic field is in range. It is low in all other cases (see Table 5 and Table 5).
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
5.2
Daisy Chain Mode
The Daisy Chain mode allows connection of several AS5045's in series, while still keeping just one digital input for data transfer (see "Data IN" in Figure 5 below). This mode is accomplished by connecting the data output (DO; pin 9) to the data input (PROG; pin 8) of the subsequent device. The serial data of all connected devices is read from the DO pin of the first device in the chain. The length of the serial bit stream increases with every connected device, it is n * (18+1) bits: e.g. 38 bit for two devices, 57 bit for three devices, etc... The last data bit of the first device (Parity) is followed by a dummy bit and the first data bit of the second device (D11), etc... (see Figure 6)
C
Data IN
AS5045 1st Device
DO PROG
AS5045 2nd Device
DO PROG
AS5045 3rd Device
DO PROG
CSn CLK CSn
CLK
CSn
CLK
CSn
CLK
Figure 5: Daisy Chain hardware configuration
CSn
tCLK FE TCLK/2 1 8 18 D 1 2 3
CLK
DO
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
OCF
COF
LIN
Mag INC
Mag Even DEC PAR
D11
D10
D9
tDO active
tDO valid Angular Position Data 1st Device Status Bits Angular Position Data 2nd Device
Figure 6: Daisy Chain mode data transfer
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
6
Pulse Width Modulation (PWM) Output
When PWMhalfEN = 1, the PWM timing is as shown in Table 7: Parameter PWM frequency MIN pulse width MAX pulse width Symbol fPWM PWMIN PWMAX Typ 122 2 8192 Unit Hz s s Note Signal period: 4097s - Position 0d - Angle 0 deg - Position 4095d - Angle 359,91 deg
The AS5045 provides a pulse width modulated output (PWM), whose duty cycle is proportional to the measured angle:
Position =
ton 4097 (ton + toff ) - 1
The PWM frequency is internally trimmed to an accuracy of 5% (10% over full temperature range). This tolerance can be cancelled by measuring the complete duty cycle as shown above.
Table 7: PWM signal parameters with half frequency (OTP option)
7
Analog Output
Angle 0 deg (Pos 0)
PWMIN
An analog output can be generated by averaging the PWM signal, using an external active or passive lowpass filter. The analog output voltage is proportional to the angle: 0= 0V; 360 = VDD5V.
4097s
1s
PWMAX 359.91 deg (Pos 4095)
4096s
Using this method, the AS5045 can be used as direct replacement of potentiometers. Pin12 PWM C1 Pin7 VSS C2 R1 R2 analog out
VDD
1/fPWM
Figure 7: PWM output signal
0V
0
360
6.1
Changing the PWM Frequency
Figure 8: Simple 2 n d order passive RC lowpass filter
The PWM frequency of the AS5045 can be divided by two by setting a bit (PWMhalfEN) in the OTP register (see chapter 8). With PWMhalfEN = 0 the PWM timing is as shown in Table 6: Parameter PWM frequency MIN pulse width MAX pulse width Symbol fPWM PWMIN PWMAX Typ 244 1 4096 Unit Hz s s Note Signal period: 4097s - Position 0d - Angle 0 deg - Position 4095d - Angle 359,91 deg
Figure 8 shows an example of a simple passive lowpass filter to generate the analog output. R1,R2 4k7 C1,C2 1F / 6V
R1 should be 4k7 to avoid loading of the PWM output. Larger values of Rx and Cx will provide better filtering and less ripple, but will also slow down the response time.
Table 6: PWM signal parameters (default mode)
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
8
Programming the AS5045
After power-on, programming the AS5045 is enabled with the rising edge of CSn and Prog = logic high. 16 bit configuration data must be serially shifted into the OTP register via the Prog pin. The first "CCW" bit is followed by the zero position data (MSB first) and the Mode setting bits (tbd). Data must be valid at the rising edge of CLK (see Figure 9). After writing the data into the OTP register it can be permanently programmed by rising the Prog pin to the programming voltage VPROG. 16 CLK pulses (tPROG) must be applied to program the fuses (Figure 10). To exit the programming mode, the chip must be reset by a poweron-reset. The programmed data is available after the next power-up. Note: During the programming process, the transitions in the programming current may cause high voltage spikes generated by the inductance of the connection cable. To avoid these spikes and possible damage to the IC, the connection wires, especially the signals Prog and VSS must be kept as short as possible. The maximum wire length between the VPROG switching transistor and pin Prog should not exceed 50mm (2 inches). To suppress eventual voltage spikes, a 10nF ceramic capacitor should be connected close to pins VPROG and VSS. This
capacitor is only required for programming, it is not required for normal operation. The clock timing tclk must be selected at a proper rate to ensure that the signal Prog is stable at the rising edge of CLK (see Figure 9). Additionally, the programming supply voltage should be buffered with a 10F capacitor mounted close to the switching transistor. This capacitor aids in providing peak currents during programming. The specified programming voltage at pin Prog is 7.3 - 7.5V (see section 0). OTP Register Contents: CCW Counter Clockwise Bit ccw=0 - angular value increases in clockwise direction ccw=1 - angular value increases in counterclockwise direction Z [11:0]: PWM dis: MagCompEn: Programmable Zero / Index Position Disable PWM output when set, activates LIN alarm both when magnetic field is too high and too low (see Table 5). when set, PWM frequency is 122Hz or 2s / step (when PWMhalfEN = 0, PWM frequency is 244Hz, 1s / step)
PWMhalfEn:
CSn
t D a ta in
PW M d is M ag C om p EN PW M h a lf EN
P ro g
CCW
Z11
Z10
Z9
Z8
Z7
Z6
Z5
Z4
Z3
Z2
Z1
Z0
C L K PROG
1
8
16
t P ro g
e n a b le
t D a ta in
v a lid
t c lk s e e te x t Z e ro / In d e x
P W M a n d s ta tu s b it m o d e s
Figure 9: Programming access - write data (section of Figure 10)
W r ite D a ta CSn
P r o g r a m m in g M o d e
P o w e r O ff
V P ro g D a ta t CLK 1
PROG PROG
PROG
18
t
Load PR O G
t
P R O G f i n is h e d
Figure 10: Complete programming sequence
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
8.1
Zero Position Programming
Zero position programming is an OTP option that simplifies assembly of a system, as the magnet does not need to be manually adjusted to the mechanical zero position. Once the assembly is completed, the mechanical and electrical zero positions can be matched by software. Any position within a full turn can be defined as the permanent new zero/index position. For zero position programming, the magnet is turned to the mechanical zero position (e.g. the "off"-position of a rotary switch) and the actual angular value is read. This value is written into the OTP register bits Z11:Z0 (see Figure 9) and programmed as described in section 8. This new absolute zero position is also the new index pulse position for incremental output modes.
In order to verify the quality of the programmed bit, an analog level can be read for each zener diode, giving an indication whether this particular bit was properly programmed or not. To put the AS5045 in Analog Readback Mode, a digital sequence must be applied to pins CSn, PROG and CLK as shown in Figure 11. The digital level for this pin depends on the supply configuration (3.3V or 5V; see section 0). The second rising edge on CSn (OutpEN) changes pin PROG to a digital output and the log. high signal at pin PROG must be removed to avoid collision of outputs (grey area in Figure 11). The following falling slope of CSn changes pin PROG to an analog output, providing a reference voltage Vref, that must be saved as a reference for the calculation of the subsequent programmed and unprogrammed OTP bits. Following this step, each rising slope of CLK outputs one bit of data in the reverse order as during programming (see Figure 9: Md0-MD1-Div0,Div1-Indx-Z0...Z11, ccw). If a capacitor is connected to pin PROG, it should be removed during analog readback mode to allow a fast readout rate. The measured analog voltage for each bit must be subtracted from the previously measured Vref, and the resulting value gives an indication on the quality of the programmed bit: a reading of <100mV indicates a properly programmed bit and a reading of >1V indicates a properly unprogrammed bit. A reading between 100mV and 1V indicates a faulty bit, which may result in an undefined digital value, when the OTP is read at power-up. Following the 18 th clock (after reading bit "ccw"), the chip must be reset by disconnecting the power supply.
Note: The zero position value may also be modified before programming, e.g. to program an electrical zero position that is 180 (half turn) from the mechanical zero position, just add 2048 to the value read at the mechanical zero position and program the new value into the OTP register.
8.2
Analog Readback Mode
Non-volatile programming (OTP) uses on-chip zener diodes, which become permanently low resistive when subjected to a specified reverse current. The quality of the programming process depends on the amount of current that is applied during the programming process (up to 130mA). This current must be provided by an external voltage source. If this voltage source cannot provide adequate power, the zener diodes may not be programmed properly.
ProgEN
OutpEN
Analog Readback Data at PROG
CSn
Vref Vprogrammed
PWM Dis Internal test bit digital
Power-onReset; turn off supply
PROG
PWM Mag halfEN Comp EN Prog changes to Output
Z0 Vunprogrammed
Z7
Z8
Z9
Z10 Z11 CCW 16
CLK
tLoadProg
1
CLKAread
Figure 11: OTP register analog read
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
9
Alignment Mode
The alignment mode simplifies centering the magnet over the center of the chip to gain maximum accuracy. Alignment mode can be enabled with the falling edge of CSn while Prog = logic high (Figure 12). The Data bits D9-D0 of the SSI change to a 10-bit displacement amplitude output. A high value indicates large X or Y displacement, but also higher absolute magnetic field strength. The magnet is properly aligned, when the difference between highest and lowest value over one full turn is at a minimum. Under normal conditions, a properly aligned magnet will result in a reading of less than 32 over a full turn. The MagINCn and MagDECn indicators will be = 1 when the alignment mode reading is < 32. At the same time, both hardware pins MagINCn (#1) and MagDECn (#2) will be pulled to VSS. A properly aligned magnet will therefore produce a MagINCn = MagDECn = 1 signal throughout a full 360 turn of the magnet. Stronger magnets or short gaps between magnet and IC may show values larger than 32. These magnets are still properly aligned as long as the difference between highest and lowest value over one full turn is at a minimum. The Alignment mode can be reset to normal operation by a power-on-reset (disconnect / re-connect power supply) or by a falling edge on CSn with Prog = low.
Prog
AlignMode enable
For 3.3V operation, the LDO must be bypassed by connecting VDD3V3 with VDD5V (see Figure 14). For 5V operation, the 5V supply is connected to pin VDD5V, while VDD3V3 (LDO output) must be buffered by a 1...10F capacitor, which is supposed to be placed close to the supply pin (see Figure 14). The VDD3V3 output is intended for internal use only It must not be loaded with an external load. The output voltage of the digital interface I/O's corresponds to the voltage at pin VDD5V, as the I/O buffers are supplied from this pin (see Figure 14).
5V Operation
1...10F
VDD3V3
100n
VDD5V
LDO
Internal VDD DO
4.5 - 5.5V
I N T E R F A C E
PWM CLK CSn
Prog VSS
CSn
Read-out via SSI
3.3V Operation
VDD3V3
100n
VDD5V
LDO
Internal VDD DO
2s 2s min. min.
Figure 12: Enabling the alignment mode
3.0 - 3.6V
Prog
exit AlignMode
CSn
Read-out via SSI
I N T E R F A C E
PWM CLK CSn
Figure 13: Exiting alignment mode
Prog VSS
10 3.3V / 5V Operation
The AS5045 operates either at 3.3V 10% or at 5V 10%. This is made possible by an internal 3.3V LowDropout (LDO) Voltage regulator. The internal supply voltage is always taken from the output of the LDO, meaning that the internal blocks are always operating at 3.3V.
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Figure 14: Connections for 5V / 3.3V supply voltages
A buffer capacitor of 100nF is recommended in both cases close to pin VDD5V.
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
11 Choosing the Proper Magnet
Typically the magnet should be 6mm in diameter and 3mm in height. Magnetic materials such as rare earth AlNiCo/SmCo5 or NdFeB are recommended.
11.1
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:
3.9 mm 3.9 mm
The magnetic field strength perpendicular to the die surface has to be in the range of 45mT...75mT (peak).
1
The magnet's field strength should be verified using a gauss-meter. The magnetic field Bv at a given distance, along a concentric circle with a radius of 1.1mm (R1), should be in the range of 45mT...75mT. (see Figure 15).
typ. 6mm diameter
2.433 mm Defined center
Rd
2.433 mm Area of recommended maximum magnet misalignment
N
S
Magnet axis R1
Figure 16: Defined chip center and magnet displacement radius
Magnet axis
Magnet Placement The magnet's center axis should be aligned within a displacement radius Rd of 0.25mm 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 (see Figure 15). The typical distance "z" between the magnet and the package surface is 0.5mm to 1.5mm, 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 MagINCn (pin 1) and MagDECn (pin 2), see Table 1.
Vertical field component
R1 concentric circle; radius 1.1mm Vertical field component Bv (45...75mT)
0
360
360
Figure 15: Typical magnet (6x3mm) and magnetic field distribution
N
Die surface
S
Package surface
z
0.576mm 0.1mm 1.282mm 0.15mm
Figure 17: Vertical placement of the magnet
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
12 Simulation Modeling
3.9 mm 0.235mm
1
The differential sampling of the sine and cosine vectors removes any common mode error due to DC components introduced by the magnetic source itself or external disturbing magnetic fields. A ratiometric division of the sine and cosine vectors removes the need for an accurate absolute magnitude of the magnetic field and thus accurate Z-axis alignment of the magnetic source.
2.433 mm 0.235mm X1
Y1 The recommended differential input range of the X2 magnetic field strength (B(X1-X2), B(Y1-Y2)) is 75mT at the surface of the die. In addition to this range, an additional offset of 5mT, caused by unwanted external stray fields is allowed.
Y2
AS5045 die
Center of die
Radius of circular Hall sensor array: 1.1mm radius
Figure 18: Arrangement of Hall sensor array on chip (principle)
The chip will continue to operate, but with degraded output linearity, if the signal field strength is outside the recommended range. Too strong magnetic fields will introduce errors due to saturation effects in the internal preamplifiers. Too weak magnetic fields will introduce errors due to noise becoming more dominant.
13 Failure Diagnostics
With reference to Figure 18, a diametrically magnetized permanent magnet is placed above or below the surface of the AS5045. The chip uses an array of Hall sensors to sample the vertical vector of a magnetic field distributed across the device package surface. The area of magnetic sensitivity is a circular locus of 1.1mm radius with respect to the center of the die. The Hall sensors in the area of magnetic sensitivity are grouped and configured such that orthogonally related components of the magnetic fields are sampled differentially. The differential signal Y1-Y2 will give a sine vector of the magnetic field. The differential signal X1-X2 will give an orthogonally related cosine vector of the magnetic field. The angular displacement () of the magnetic source with reference to the Hall sensor array may then be modelled by: The AS5045 also offers several diagnostic and failure detection features:
13.1
Magnetic Field Strength Diagnosis
By software: the MagINC and MagDEC status bits will both be high when the magnetic field is out of range. By hardware: Pins #1 (MagINCn) and #2 (MagDECn) are open-drain outputs and will both be turned on (= low with external pull-up resistor) when the magnetic field is out of range. If only one of the outputs are low, the magnet is either moving towards the chip (MagINCn) or away from the chip (MagDECn).
13.2
Power Supply Failure Detection
= arctan
(Y 1 - Y 2) 0.5 ( X 1 - X 2)
By software: If the power supply to the AS5045 is interrupted, the digital data read by the SSI will be all "0"s. Data is only valid, when bit OCF is high, hence a data stream with all "0"s is invalid. To ensure adequate low levels in the failure case, a pull-down resistor (~10k) should be added between pin DO and VSS at the receiving side By hardware: The MagINCn and MagDECn pins are open drain outputs and require external pull-up resistors. In normal operation, these pins are high ohmic and the outputs are high (see Table 5). In a failure case, either when the magnetic field is out of range of the power supply is missing, these outputs will become low. To ensure adequate low levels in case of a broken power supply to the AS5045, the pull-up resistors (~10k) from
The 0.5 angular error assumes a magnet optimally aligned over the center of the die and is a result of gain mismatch errors of the AS5045. Placement tolerances of the die within the package are 0.235mm in X and Y direction, using a reference point of the edge of pin #1 (see Figure 18) In order to neglect the influence of external disturbing magnetic fields, a robust differential sampling and ratiometric calculation algorithm has been implemented.
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
each pin must be connected to the positive supply at pin 16 (VDD5V). By hardware: PWM output: The PWM output is a constant stream of pulses with 1kHz repetition frequency. In case of power loss, these pulses are missing
6
Linearity Error over XY-misalignment []
14 Angular Output Tolerances
14.1 Accuracy
5 4 3 2 1 0 0 1000 800 600 -200 -400 400 -600 200 0 -200 -800 -400 -600 -1000 -800 -1000 x 1000 800 600 400 200
Accuracy is defined as the error between measured angle and 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 As a sum of all these errors, the accuracy with centered magnet = (Errmax - Errmin)/2 is specified as better than 0.5 degrees @ 25C (see Figure 20). Misalignment of the magnet further reduces the accuracy. Figure 19 shows an example of a 3D-graph displaying non-linearity over XY-misalignment. The center of the square XY-area corresponds to a centered magnet (see dot in the center of the graph). The X- and Y- axis 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 100m. For each misalignment step, the measurement as shown in Figure 20 is repeated and the accuracy (Errmax - Errmin)/2 (e.g. 0.25 in Figure 20) is entered as the Z-axis in the 3D-graph.
y
Figure 19: Example of linearity error over XY misalignment
The maximum non-linearity error on this example is better than 1 degree (inner circle) over a misalignment radius of ~0.7mm. 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 1.4 degrees. The magnet used for this measurement was a cylindrical NdFeB (Bomatec(R) BMN-35H) magnet with 6mm diameter and 2.5mm in height.
Linearity error with centered magnet [degrees] 0.5 0.4 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5 1 55 109 163 217 271 325 379 433 487 541 595 649 703 757 811 865 919 973
transition noise Err m ax
Err m in
Figure 20: Example of linearity error over 360
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14.2
Transition Noise
nslow mod e = n fast mod e =
60 rpm 384 s 60 rpm 96 s
Transition noise is defined as the jitter in the transition between two steps. Due to the nature of the measurement principle (Hall sensors + Preamplifier + ADC), there is always a certain degree of noise involved. This transition noise voltage results in an angular transition noise at the outputs. It is specified as 0.03 degrees rms (1 sigma) *1 .
The upper speed limit in slow mode is ~6.000rpm and ~30.000rpm in fast mode. The only restriction at high speed is that there will be fewer samples per revolution as the speed increases (see Table 2). Regardless of the rotational speed, the absolute angular value is always sampled at the highest resolution of 12 bit.
This is the repeatability of an indicated angle at a given mechanical position. The transition noise has different implications on the type of output that is used: Absolute output; SSI interface: The transition noise of the absolute output can be reduced by the user by implementing averaging of readings. An averaging of 4 readings will reduce the transition noise by 50% = 0.015 rms (1 sigma). PWM interface: If the PWM interface is used as an analog output by adding a low pass filter, the transition noise can be reduced by lowering the cutoff frequency of the filter. If the PWM interface is used as a digital interface with a counter at the receiving side, the transition noise may again be reduced by averaging of readings.
14.4
Propagation Delays
The propagation delay is the delay between the time that the sample is taken until it is converted and available as angular data. This delay is 96s in fast mode and 384s in slow mode. Using the SSI interface for absolute data transmission, an additional delay must be considered, caused by the asynchronous sampling (0 ... 1/fsample) and the time it takes the external control unit to read and process the angular data from the chip (maximum clock rate = 1MHz, number of bits per reading = 18). 14.4.1 Angular Error Caused by Propagation Delay
A rotating magnet will cause an angular error caused by the output propagation delay. This error increases linearly with speed: e sampling , = rpm 6 * prop.delay where esampling = angular error [] rpm = rotating speed [rpm] prop.delay = propagation delay [seconds] Note: since the propagation delay is known, it can be automatically compensated by the control unit processing the data from the AS5045.
*1
: statistically, 1 sigma represents 68.27% of readings, 3 sigma represents 99.73% of readings.
14.3
14.3.1
High Speed Operation
Sampling Rate
The AS5045 samples the angular value at a rate of 2.61k (slow mode) or 10.42k (fast mode, selectable by pin MODE) samples per second. Consequently, the absolute outputs are updated each 384s (96s in fast mode). At a stationary position of the magnet, the sampling rate creates no additional error.
Absolute Mode At a sampling rate of 2.6kHz/10.4kHz, the number of samples (n) per turn for a magnet rotating at high speed can be calculated by
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14.5
Internal Timing Tolerance
14.6
14.6.1
Temperature
Magnetic Temperature Coefficient
The AS5045 does not require an external ceramic resonator or quartz. All internal clock timings for the AS5045 are generated by an on-chip RC oscillator. This oscillator is factory trimmed to 5% accuracy at room temperature (10% over full temperature range). This tolerance influences the ADC sampling rate and the pulse width of the PWM output:
Absolute output; SSI interface: A new angular value is updated every 400s (typ.) PWM output: A new angular value is updated every 400s (typ.). The PWM pulse timings Ton and Toff also have the same tolerance as the internal oscillator (see above). If only the PWM pulse width Ton is used to measure the angle, the resulting value also has this timing tolerance. However, this tolerance can be cancelled by measuring both Ton and Toff and calculating the angle from the duty cycle (see section 6):
One of the major benefits of the AS5045 compared to linear Hall sensors is that it is much less sensitive to temperature. While linear Hall sensors require a compensation of the magnet's temperature coefficients, the AS5045 automatically compensates for the varying magnetic field strength over temperature. The magnet's temperature drift does not need to be considered, as the AS5045 operates with magnetic field strengths from 45...75mT.
Example: A NdFeB magnet has a field strength of 75mT @ -40C and a temperature coefficient of -0.12% per Kelvin. The temperature change is from -40 to +125 = 165K. The magnetic field change is: 165 x -0.12% = -19.8%, which corresponds to 75mT at -40C and 60mT at 125C. The AS5045 can compensate for this temperature related field strength change automatically, no user adjustment is required.
Position =
ton 4097 (ton + toff ) - 1
14.7
Accuracy over Temperature
The influence of temperature in the absolute accuracy is very low. While the accuracy is 0.5 at room temperature, it may increase to 0.9 due to increasing noise at high temperatures. 14.7.1 Timing Tolerance over Temperature
The internal RC oscillator is factory trimmed to 5%. Over temperature, this tolerance may increase to 10%. Generally, the timing tolerance has no influence in the accuracy or resolution of the system, as it is used mainly for internal clock generation. The only concern to the user is the width of the PWM output pulse, which relates directly to the timing tolerance of the internal oscillator. This influence however can be cancelled by measuring the complete PWM duty cycle instead of just the PWM pulse (see 14.5).
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15 Electrical Characteristics
15.1 AS5045 Differences to AS5040
AS5045 12bits, 0.088/step. read: 18bits (12bits data + 6 bits status) OTP write: 18 bits (12bits zero position + 6 bits mode selection) Not used Pin 3: not used Pin 4:not used MagINCn, MagDECn: same feature as AS5040, additional OTP option for red-yellow-green magnetic range MODE pin, switch between fast and slow mode PWM output: frequency selectable by OTP: 1s / step, 4096 steps per revolution, f=244Hz 2s/ step, 4096 steps per revolution, f=122Hz selectable by MODE input pin: 2.5kHz, 10kHz 384s (slow mode) 96s (fast mode) 0.03 degrees max. (slow mode) 0.06 degrees max. (fast mode) zero position, rotational direction, PWM disable, 2 Magnetic Field indicator modes, 2 PWM frequencies AS5040 10bits, 0.35/step read: 16bits (10bits data + 6 bits status) OTP write: 16 bits (10bits zero position + 6 bits mode selection) quadrature, step/direction and BLDC motor commutation modes Pin 3:incremental output A_LSB_U Pin 4:incremental output B_DIR_V MagINCn, MagDECn indicate in-range or out-of-range magnetic field plus movement of magnet in z-axis Pin 6:Index output PWM output: 1s / step, 1024 steps per revolution, 976Hz PWM frequency fixed at 10kHz @10bit resolution 48s 0.12 degrees zero position, rotational direction, incremental modes, index bit width All parameters are according to AS5040 datasheet except for the parameters shown below: Building Block Resolution Data length
incremental encoder
Pins 1 and 2
Pin 6 Pin 12
sampling frequency Propagation delay Transition noise OTP programming options
15.2
Absolute Maximum Ratings (non operating)
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.
Parameter DC supply voltage at pin VDD5V DC supply voltage at pin VDD3V3 Input pin voltage Input current (latchup immunity) Electrostatic discharge Storage temperature Body temperature (Lead-free package) Humidity non-condensing
Symbol VDD5V VDD3V3 Vin Iscr ESD Tstrg TBody H
Min -0.3
Max 7 5
Unit V V V mA kV
Note
-0.3 -100 2 -55
VDD5V +0.3 100
Except VDD3V3 Norm: JEDEC 78 Norm: MIL 883 E method 3015 Min - 67F ; Max +257F t=20 to 40s, Norm: IPC/JEDEC J-Std-020C Lead finish 100% Sn "matte tin"
125 260
C C %
5
85
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15.3
Operating Conditions
Symbol Tamb Isupp VDD5V VDD3V3 VDD5V VDD3V3 4.5 3.0 3.0 3.0 Min -40 16 5.0 3.3 3.3 3.3 Typ Max 125 20 5.5 3.6 3.6 3.6 Unit C mA V V V V 5V Operation 3.3V Operation (pin VDD5V and VDD3V3 connected) Note -40F...+257F
Parameter Ambient temperature Supply current Supply voltage at pin VDD5V Voltage regulator output voltage at pin VDD3V3 Supply voltage at pin VDD5V Supply voltage at pin VDD3V3
15.4
15.4.1
DC Characteristics for Digital Inputs and Outputs
CMOS Schmitt-Trigger Inputs: CLK, CSn. (CSn = internal Pull-up)
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter High level input voltage Low level input voltage Schmitt Trigger hysteresis Input leakage current Pull-up low level input current
Symbol VIH VIL VIon- VIoff ILEAK IiL
Min 0.7 * VDD5V
Max 0.3 * VDD5V
Unit V V V A A
Note Normal operation
1 -1
-30
1
-100
CLK only CSn only, VDD5V: 5.0V
15.4.2
CMOS / Program Input: Prog
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter High level input voltage High level input voltage Low level input voltage High level input current
Symbol VIH VPROG VIL IiL
Min 0.7 * VDD5V
Max VDD5V
Unit V V V A
Note
See "programming conditions" 0.3 * VDD5V 30 100
During programming
VDD5V: 5.5V
15.4.3
CMOS Output Open Drain: MagINCn, MagDECn
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter Low level output voltage Output current Open drain leakage current
Symbol VOL IO IOZ
Min
Max VSS+0.4 4 2 1
Unit V mA A
Note VDD5V: 4.5V VDD5V: 3V
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15.4.4
CMOS Output: PWM
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter High level output voltage Low level output voltage Output current
Symbol VOH VOL IO
Min VDD5V-0.5
Max VSS+0.4 4 2
Unit V V mA mA
Note
VDD5V: 4.5V VDD5V: 3V
15.4.5
Tristate CMOS Output: DO
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter High level output voltage Low level output voltage Output current Tri-state leakage current
Symbol VOH VOL IO IOZ
Min VDD5V -0.5
Max VSS+0.4 4 2 1
Unit V V mA mA A
Note
VDD5V: 4.5V VDD5V: 3V
15.5
Magnetic Input Specification
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Two-pole cylindrical diametrically magnetised source: Parameter Diameter Magnetic input field amplitude Magnetic offset Field non-linearity Input frequency (rotational speed of magnet) Displacement radius Eccentricity Recommended magnet material and temperature drift fmag_abs Symbol dmag Bpk Boff Min 4 45 75 10 5 2,44 0,61 Disp Ecc
-0.12 -0.035
Typ
Max
Unit mm mT mT % Hz
Note Recommended diameter: 6mm for cylindrical magnets Required vertical component of the magnetic field strength on the die's surface, measured along a concentric circle with a radius of 1.1mm Constant magnetic stray field Including offset gradient 146 rpm @ 4096 positions/rev.; fast mode 36.6rpm @ 4096 positions/rev.; slow mode
0.25 100
mm m
%/K
Max. offset between defined device center and magnet axis (see Figure 16) Eccentricity of magnet center to rotational axis NdFeB (Neodymium Iron Boron) SmCo (Samarium Cobalt)
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15.6
Electrical System Specifications
Symbol RES INLopt INLtemp Min Typ Max 12 0.5 0.9 Unit bit deg deg Note 0.088 deg Maximum error with respect to the best line fit. Centered magnet without calibration, Tamb =25 C. Maximum error with respect to the best line fit. Centered magnet without calibration, Tamb = -40 to +125C Best line fit = (Errmax - Errmin) / 2 Over displacement tolerance with 6mm diameter magnet, without calibration, Tamb = -40 to +125C 12bit, no missing codes 1 sigma, fast mode (MODE = 1) 1 sigma, slow mode (MODE=0 or open) DC supply voltage 3.3V (VDD3V3) DC supply voltage 3.3V (VDD3V3) Fast mode (Mode = 1); Until status bit OCF = 1 Slow mode (Mode = 0 or open); Until OCF = 1 Fast mode (MODE=1) Slow mode (MODE=0 or open) Tamb = 25C, slow mode (MODE=0 or open) kHz kHz MHz Tamb = -40 to +125C, slow mode (MODE=0 or open) Tamb = 25C, fast mode (MODE = 1) Tamb = -40 to +125C, : fast mode (MODE = 1) Max. clock frequency to read out serial data
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter Resolution Integral non-linearity (optimum) Integral non-linearity (optimum)
Integral non-linearity Differential non-linearity Transition noise Power-on reset thresholds
On voltage; 300mV typ. hysteresis Off voltage; 300mV typ. hysteresis
INL DNL TN Von Voff tPwrUp 1,37 1.08 0.03 0.015 2.2 1.9
1.4 0.044 0.06 0.03 2.9 2.6 20 80 96 384 2.48 2.61 2.61 10.42 10.42 2.74 2.87 10.94 11.46 1
deg deg Deg RMS V V ms
Power-up time System propagation delay absolute output : delay of ADC, DSP and absolute interface Internal sampling rate for absolute output: Internal sampling rate for absolute output Read-out frequency
tdelay
s
fS fS CLK
2.35 9.90 9.38
4095
12bit code
2 1 0
4095
Actual curve TN DNL+1LSB INL 0.09 Ideal curve
2048
2048
0 0 180
Figure 21: Integral and differential non-linearity (example)
360
[degrees]
Integral Non-Linearity (INL) is the maximum deviation between actual position and indicated position. Differential Non-Linearity (DNL) is the maximum deviation of the step length from one position to the next.
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Transition Noise (TN) is the repeatability of an indicated position
16 Timing Characteristics
Synchronous Serial Interface (SSI)
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter Data output activated (logic high) First data shifted to output register Start of data output Data output valid Data output tristate Pulse width of CSn Read-out frequency
Symbol t DO active tCLK FE T CLK / 2 t DO valid t DO tristate t CSn fCLK
Min
Typ
Max 100
Unit ns ns ns
Note Time between falling edge of CSn and data output activated Time between falling edge of CSn and first falling edge of CLK Rising edge of CLK shifts out one bit at a time Time between rising edge of CLK and data output valid After the last bit DO changes back to "tristate" CSn = high; To initiate read-out of next angular position Clock frequency to read out serial data
500 500 375 100 500 >0 1
ns ns ns MHz
16.1.1
Pulse Width Modulation Output
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter PWM frequency Minimum pulse width
Symbol f PWM PW MIN
Min 232 220 0.95
Typ 244 244 1
Max 256 268 1.05
Unit Hz s
Note Signal period = 4097s 5% at Tamb = 25C =4097s 10% at Tamb = -40 to +125C Position 0d; Angle 0 degree
Maximum pulse width PW MAX 3891 4096 4301 s Position 4095d; Angle 359.91 degrees Note: when OTP bit "PWMhalfEn" is set, the PWM pulse width PW is doubled (PWM frequency fPWM is divided by 2)
16.2
Programming Conditions
Symbol t Prog enable t Data in t Data in valid t Load PROG CLK PROG t PROG t PROG finished V PROG I PROG
CLKAread Vprogrammed Vunprogrammed 1
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter Programming enable time Write data start Write data valid Load Programming data Write data - programming CLK PROG CLK pulse width Hold time of Vprog after programming Programming voltage, pin PROG Programming current
Analog Read CLK Programmed Zener Voltage (log.1) Unprogrammed Zener Voltage (log. 0)
Min 2 2 250 3
Typ
Max
Unit s s ns s
Note Time between rising edge at Prog pin and rising edge of CSn Write data at the rising edge of CLK PROG ensure that VPROG is stable with rising edge of CLK during programming; 16 clock cycles Programmed data is available after next power-on Must be switched off after zapping during programming Analog Readback mode VRef-VPROG during Analog Readback mode (see 8.2)
250 1.8 2 7.3 7.4 7.5 130
100 100
kHz s s V mA
kHz mV V
2
2.2
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17 Package Drawings and Markings
16-Lead Shrink Small Outline Package SSOP-16
AYWWIZZ AS5045
Dimensions
Symbol A A1 A2 b c D E E1 e K L 0 0.63 mm Min 1.73 0.05 1.68 0.25 0.09 6.07 7.65 5.2 Typ 1.86 0.13 1.73 0.315 6.20 7.8 5.3 0.65 0.75 8 0.95 0 .025 Max 1.99 0.21 1.78 0.38 0.20 6.33 7.9 5.38 Min .068 .002 .066 .010 .004 .239 .301 .205 inch Typ .073 .005 .068 .012 .244 .307 .209 .0256 .030 8 .037 Max .078 .008 .070 .015 .008 .249 .311 .212
Marking: AYWWIZZ A: Pb-Free Identifier Y: Last Digit of Manufacturing Year WW: Manufacturing Week I: Plant Identifier ZZ: Traceability Code
JEDEC Package Outline Standard: MO - 150 AC Thermal Resistance Rth(j-a): 79.4 K/W in still air, soldered on PCB IC's marked with a white dot or the letters "ES" denote Engineering Samples
18 Ordering Information
Delivery: Tape and Reel (1 reel = 2000 devices) Tubes (1 box = 100 tubes a 77 devices)
Order # AS5045 for delivery in tubes Order # AS5045TR for delivery in tape and reel
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19 Recommended PCB Footprint:
Recommended Footprint Data A B C D E mm 9.02 6.16 0.46 0.65 5.01 inch 0.355 0.242 0.018 0.025 0.197
20 Revision History
Revision 1.0 Date Dec. 7, 2004 Sep. 26, 2005 Jan. 11, 2006
Initial revision Official release Modify Figure 1, thermal resistance (Package Drawings and Markings)
Description
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21 Contact
21.1 Headquarters
austriamicrosystems AG A 8141 Schloss Premstatten, Austria Phone: Fax: +43 3136 500 0 +43 3136 525 01
austriamicrosystems USA, Inc. 8601 Six Forks Road Suite 400 Raleigh, NC 27615, USA Phone: Fax: +1 919 676 5292 +1 509 696 2713
industry.medical@austriamicrosystems.com www.austriamicrosystems.com
21.2
Sales Offices
austriamicrosystems Germany GmbH Tegernseer Landstrasse 85 D-81539 Munchen, Germany Phone: Fax: +49 89 69 36 43 0 +49 89 69 36 43 66
austriamicrosystems USA, Inc. 4030 Moorpark Ave Suite 116 San Jose, CA 95117, USA Phone: Fax: +1 408 345 1790 +1 509 696 2713
austriamicrosystems Italy S.r.l. Via A. Volta, 18 I-20094 Corsico (MI), Italy Phone: Fax: +39 02 4586 4364 +39 02 4585 773
austriamicrosystems AG Suite 811, Tsimshatsui Centre East Wing, 66 Mody Road Tsim Sha Tsui East, Kowloon, Hong Kong Phone: Fax: +852 2268 6899 +852 2268 6799
austriamicrosystems France S.A.R.L. 124, Avenue de Paris F-94300 Vincennes, France Phone: Fax: +33 1 43 74 00 90 +33 1 43 74 20 98
austriamicrosystems Switzerland AG Rietstrasse 4 CH 8640 Rapperswil, Switzerland Phone: Fax: +41 55 220 9008 +41 55 220 9001
austriamicrosystems AG AIOS Gotanda Annex 5 t h Fl., 1-7-11, Higashi-Gotanda, Shinagawa-ku Tokyo 141-0022, Japan Phone: Fax: +81 3 5792 4975 +81 3 5792 4976
austriamicrosystems UK, Ltd. 88, Barkham Ride, Finchampstead, Wokingham Berkshire RG40 4ET, United Kingdom Phone: Fax: +44 118 973 1797 +44 118 973 5117
austriamicrosystems AG #805, Dong Kyung Bldg., 824-19, Yeok Sam Dong, Kang Nam Gu, Seoul Korea 135-080 Phone: Fax: +82 2 557 8776 +82 2 569 9823
austriamicrosystems AG Klaavuntie 9 G 55 FI 00910 Helsinki, Finland Phone: Fax: +358 9 72688 170 +358 9 72688 171
austriamicrosystems AG Singapore Representative Office 83 Clemenceau Avenue, #02-01 UE Square 239920, Singapore Phone: Fax: +65 68 30 83 05 +65 62 34 31 20
austriamicrosystems AG Bivagen 3B S 19163 Sollentuna, Sweden Phone: +46 8 6231 710
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AS5045 12-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
Copyright
Devices sold by austriamicrosystems are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. austriamicrosystems 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 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 for current information. This product is intended for use in normal commercial applications. Copyright (c) 2005 austriamicrosystems. Trademarks registered (R). 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. To the best of its knowledge, austriamicrosystems asserts that the information contained in this publication is accurate and correct. However, austriamicrosystems 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 rendering of technical or other services.
Revision 1.0, 11-Jan-06
www.austriamicrosystems.com
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