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AS5043 Programmable 360 Magnetic Angle Encoder
AS5043 PROGRAMMABLE 360 MAGNETIC ANGLE ENCODER WITH ABSOLUTE SSI AND ANALOG OUTPUTS
PRELIMINARY DATA SHEET DATA SHEET
1
General Description
3
Key Features
The AS5043 is a contactless magnetic angle encoder for accurate measurement up to 360. It is a system-on-chip, combining integrated Hall elements, analog front end and digital signal processing in a single device. The AS5043 provides a digital 10-bit as well as a programmable analog output that is directly proportional to the angle of a magnet, rotating over the chip. The analog output can be configured in many ways, including user programmable angular range, adjustable output voltage range, voltage or current output, etc.. An internal voltage regulator allows operation of the AS5043 from 3.3V or 5.0V supplies.
360 contactless high resolution angular position encoding User programmable zero position Two 10-bit absolute outputs: Serial digital interface and Versatile analog output programmable angular range up to 360 programmable ratiometric output voltage range Failure detection mode for magnet field strength and loss of power supply Serial read-out of multiple interconnected AS5043 devices using daisy chain mode Mode input for optimizing noise vs. speed Alignment mode for magnet placement guidance Wide temperature range: - 40C to + 125C Small package: SSOP 16 (5.3mm x 6.2mm)
4
Applications
The AS5043 is ideal for applications with an angular travel range from a few degrees up to a full turn of 360, such as
Figure 1: Typical arrangement of AS5043 and magnet
-
2
Benefits
-
Complete system-on-chip - Flexible system solution provides absolute output, both digital and analog - Angle measurement with software programmable range up to 360 - High reliability due to non-contact magnetic sensing - Ideal for applications in harsh environments - Robust system, tolerant to magnet misalignment, airgap variations, temperature variations and external magnetic fields - No calibration required
Industrial applications: - Contactless rotary position sensing - Robotics - Valve Controls Automotive applications: - Throttle position sensors - Gas / brake pedal position sensing - Headlight position control
Front panel rotary switches Replacement of potentiometers
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AS5043 Programmable 360 Magnetic Angle Encoder
Table 1: Pin description SSOP16
5
Pin Configuration
DO_OD DI_PD state DI_PU input AI DI digital output open drain S supply pin digital input pull-down DO_T digital output /tridigital input pull-up analog input digital input ST AO schmitt-trigger analog output
AS5043
5.1
Figure 2: AS5043 pin configuration SSOP16
Pin Description
Pins 7, 15 and 16 are supply pins, pins 5, 13 and 14 are for internal use and must be left open. Pin 1 is the magnetic field strength indicator, MagRNGn. It is an open-drain output that is pulled to VSS when the magnetic field is out of the recommended range (45mT to 75mT). The chip will still continue to operate, but with reduced performance, when the magnetic field is out of range. When this pin is low, the analog output at pins #10 and #12 will be 0V to indicate the out-of-range condition. Pin 2 MODE allows switching between filtered (slow) and unfiltered (fast mode). See section 9. Pin 3 Chip Select (CSn; active low) selects a device for serial data transmission over the SSI interface. A "logic high" at CSn forces output DO to digital tristate. Pin 4 CLK is the clock input for serial data transmission over the SSI interface (see section 8) Pin 6 DO (Data Out) is the serial data output during data transmission over the SSI interface (see section 8) Pin 8 PROG_DI is used to program the different operation modes, as well as the zero-position in the OTP register. This pin is also used as a digital input to shift serial data through the device in Daisy Chain Configuration, (see page 6). Pin 9 DACref is the external voltage reference input for the Digital-to-Analog Converter (DAC). If selected, the analog output voltage on pin 12 (Vout) will be ratiometric to the voltage on this pin. Pin10 DACout is the unbuffered output of the DAC. This pin may be used to connect an external OPAMP, etc. to the DAC. Pin 11 FB (Feedback) is the inverting input of the OPAMP buffer stage.
Package = SSOP16 (16 lead Shrink Small Outline Package)
Pin Symbol Type Description Magnet Field Magnitude RaNGe warning; active low, indicates that the magnetic field strength is outside of the recommended limits. Mode input. Select between low noise (open, low) and high speed (high) mode. Internal pull-down resistor Chip Select, active low; Schmitt-Trigger input, internal pull-up resistor (~50k) Clock Input of Synchronous Serial Interface; Schmitt-Trigger input must be left unconnected Data Output of Synchronous Serial Interface Negative Supply Voltage (GND) OTP Programming Input and Data Input for Daisy Chain mode. Internal pull-down 8 Prog_DI DI_PD resistor (~74k). Should be connected to VSS if programming is not used DAC Reference voltage input for external reference DAC output (unbuffered, Ri ~8k) Feedback, OPAMP inverting input OPAMP output Must be left unconnected Must be left unconnected 3V-Regulator Output for internal core, regulated from VDD5V.Connect to VDD5V for 3V supply voltage. Do not load externally. Positive Supply Voltage, 3.0 to 5.5 V
1
MagRngn
DO_OD
2
Mode
DI_PD, ST DI_PU, ST DI,ST DO_T S
3 4 5 6 7
CSn CLK NC DO VSS
9 10 11 12 13 14
DACref DACout FB Vout NC NC
AI AO
AI AO
-
15
VDD3V3
S
16
VDD5V
S
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AS5043 Programmable 360 Magnetic Angle Encoder
Access to this pin allows various OPAMP configurations. Pin 12 Vout is the analog output pin. The analog output is a DC voltage, ratiometric to VDD5V (3.0 - 5.5V) or an external voltage source and proportional to the angle.
angular representation is converted to an analog signal, ratiometric to the supply voltage. The analog output can be configured in many ways, such as 360/180/90 or 45 angular range, external or internal DAC reference voltage, 0-100%*VDD or 1090% *VDD analog output range, external or internal amplifier gain setting. The various output modes as well as a user programmable zero position can be programmed in an OTP register. As long as no programming voltage is applied to pin PROG, the new setting may be overwritten at any time and will be reset to default when power is cycled. To make the setting permanent, the OTP register must be programmed by applying a programming voltage. The AS5043 is tolerant to magnet misalignment and unwanted external magnetic fields due to differential measurement technique and Hall sensor conditioning circuitry. It is also tolerant to airgap and temperature variations due to Sin-/Cos- signal evaluation.
6
Functional Description
The AS5043 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 in a circle around the center of the device and deliver a voltage representation of the magnetic field perpendicular to the surface of the IC. Through Sigma-Delta Analog / Digital Conversion and Digital Signal-Processing (DSP) algorithms, the AS5043 provides accurate high-resolution absolute angular 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 indicate movements of the magnet towards or away from the chip and to indicate, when the magnetic field is outside of the recommended range (status bits = MagInc, MagDec; hardware pin = MagRngn). A small low cost diametrically magnetized (two-pole) standard magnet, centered over the chip, is used as the input device. The AS5043 senses the orientation of the magnetic field and calculates a 10-bit binary code. This code can be accessed via a Synchronous Serial Interface (SSI). In addition, the absolute
MagRNGn Mode Sin Ang DO Cos Mag CSn CLK DACref 10 FB
Vout
+
DACout Prog_DI
Figure 3: AS5043 block diagram
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AS5043 Programmable 360 Magnetic Angle Encoder
7
3.3V / 5V Operation 8 10-bit Absolute Synchronous Serial Interface (SSI)
The AS5043 operates either at 3.3V 10% or at 5V 10%. This is made possible by an internal 3.3V LowDropout (LDO) Voltage regulator. The core supply voltage is always taken from the LDO output, as the internal blocks are always operating at 3.3V. For 3.3V operation, the LDO must be bypassed by connecting VDD3V3 with VDD5V (see Figure 4 ). For 5V operation, the 5V supply is connected to pin VDD5V, while VDD3V3 (LDO output) must be buffered by a 1...10F capacitor, which should be placed close to the supply pin (see). The VDD3V3 output is intended for internal use only It should not be loaded with an external load. The voltage levels of the digital interface I/O's correspond to the voltage at pin VDD5V, as the I/O buffers are supplied from this pin (see Figure 4).
The serial data transmission timing is outlined in Figure 5: if CSn changes to logic low, Data Out (DO) will change from high impedance (tri-state) to logic high and the read-out sequence 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 16 bits, the first 10 bits are the angular information D[9:0], the subsequent 6 bits contain system information, about the validity of data such as OCF, COF, LIN, Parity and Magnetic Field status (increase / decrease / out of range) . A subsequent measurement is initiated by a logic "high" pulse at CSn with a minimum duration of tCSn. Data transmission may be terminated at any time by pulling CSn = high.
8.1
Serial Data Contents:
D9:D0 absolute angular position data (MSB is clocked out first). OCF (Offset Compensation Finished), logic high indicates that the Offset Compensation Algorithm has finished and data is valid. 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 may contain invalid data. This warning may be resolved by bringing the magnet within the X-Y-Z tolerance limits. Data D9:D0 is valid, when the status bits have the following configurations:
OCF COF LIN Mag INC Mag DEC Parity
0 1 0 0 0 1
Figure 4: Connections for 5V / 3.3V supply voltages
0 1 0
even checksum of bits 1:15
Table 2: Status bit outputs
A buffer capacitor of 100nF is recommended in both cases close to pin VDD5V.
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AS5043 Programmable 360 Magnetic Angle Encoder
MagInc, (Magnitude Increase) becomes HIGH, when the magnet is pushed towards the IC, thus the magnetic field strength is increasing. MagDec, (Magnitude Decrease) becomes HIGH, when the magnet is pulled away from the IC, thus the magnetic field strength is decreasing. Both signals HIGH indicate a magnetic field that is out of the allowed range (see Table 3).
Note: Pin 1 (MagRngn) is a combination of MagInc and MagDec. It is active low via an open drain output and requires an external pull-up resistor. If the magnetic field is in range, this output is turned off. (logic "high"). Even Parity bit for transmission error detection of bits 1...15 (D9...D0, OCF, COF, LIN, MagInc, MagDec) The absolute angular output is always set to a resolution of 10 bit / 360. Placing the magnet above the chip, angular values increase in clockwise direction by default.
CSn
t CLK FE
T CLK / 2
1 8 16
t CSn
t CLK FE
CLK
1
DO
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
OCF
COF
LIN
Mag INC
Mag DEC
Even PAR
D9
t DO active
t DO valid
Angular Position Data
Status Bits
t DO Tristate
Figure 5: Synchronous serial interface with absolute angular position data
8.2
Z-Axis Range Indication (Push Button Feature, Red/Yellow/Green Indicator)
Additionally, the analog output provides a safety feature in the form that it will be turned off when the magnetic field is too strong or too weak (RED range). The serial data is always available, the red/yellow/green status is indicated by the status bits as shown below:
The AS5043 provides several options of detecting movement and distance of the magnet in the vertical (Z-) direction. Signal indicators MagINC, MagDEC and LIN are available as status bits in the serial data stream, while MagRngn is an open-drain output that indicates an out-of range status (on in YELLOW or RED range).
SSI Status bits Mag INC 0 0 1 1 Mag DEC 0 1 0 1 LIN Hardware Pins Mag Rngn Off Off Off On Analog output enabled enabled enabled enabled
Description
0 0 0 0
No distance change Magnetic Input Field OK (GREEN range, ~45...75mT) Distance increase, GREEN range; Pull-function. This state is dynamic and only active while the magnet is moving away from the chip. Distance decrease, GREEN range; Push- function. This state is dynamic and only active while the magnet is moving towards the chip. YELLOW Range: Magnetic field is ~ 25...45mT or ~75...135mT. The AS5043 may still be operated in this range, but with slightly reduced accuracy. RED Range: Magnetic field is ~<25mT or >~135mT. The analog output will be turned off in this range by default. It can be enabled permanently by OTP programming (see 11.1.2). It is still possible to use the absolute serial interface in the red range, but not recommended.
Table 3: Magnetic field strength indicators
1
1
1
On
disabled
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AS5043 Programmable 360 Magnetic Angle Encoder
9
Mode Input Pin
increase to <0.06 rms. This mode is recommended for higher speed and full scale = 360 applications. Switching the parameters: MODE pin affects the following
The absolute angular position is sampled at a rate of 10.4kHz (t=96s) in fast mode and at a rate of 2.6kHz (t=384s) in slow mode. These modes are selected by pin MODE (#2). The mode input pin activates or deactivates an internal filter, which is used to reduce the digital jitter and consequently the analog output noise.
Parameter sampling rate
slow mode (Pin MODE = 0 or open) 2.61 kHz (383s)
fast mode (Pin MODE = 1) 10.42 kHz (95.9s) 0.06 rms 96s 80ms
Activating the filter by pulling Mode = LOW or leaving it open reduces the transition noise to <0.03 rms. At the same time, the sampling rate is reduced to 2.6kHz and the signal propagation delay is increased to 384s. This mode is recommended for high precision, low speed and 360 applications. Deactivating the filter by setting Mode = HIGH increases the sampling rate to 10.4kHz and reduces the signal propagation delay to 96s. The transition noise will
transition noise (1 sigma) propagation delay Startup time
0.03 rms 384s 20ms
Table 4: Mode pin settings
Pin MODE should be set at power-up. A mode change during operation is not recommended.
10 Daisy Chain Mode
The Daisy Chain Mode allows connection of several AS5043's in series, while still keeping just one digital input for data transfer (See "Data IN" in Figure 6 ). 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 * (16+1) bits: e.g. 34 bit for two devices, 51 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 (D9), etc... (see Figure 7)
CSn t C LK FE T CLK/2
1 8 16 D 1 2 3
C
Data IN
AS5043 1st Device
DO PROG
AS5043 2nd Device
DO PROG
AS5043 3rd Device
DO PROG
CSn CLK CSn
CLK
CSn
CLK
CSn
CLK
Figure 6: Daisy Chain hardware configuration
CLK
DO
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
O CF
CO F
LIN
M ag INC
M ag DEC
Even PAR
D9
D8
D7
t D O active
t DO valid
Angular Position Data 1 Device
st
Status Bits
Angular Position Data 2 nd Device
Figure 7: Daisy Chain data transfer timing diagram
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AS5043 Programmable 360 Magnetic Angle Encoder
11 Analog Output
The analog output Vout provides an analog voltage that is proportional to the angle of the rotating magnet and ratiometric to the supply voltage VDD5V (max.5.5V). It can source or sink currents up to 1mA in normal operation (up to 66mA short circuit current). The analog output block consists of a digital angular range selector, a 10-bit Digital-to-Analog converter and an OPAMP buffer stage (see Figure 14). The digital range selector allows a preselection of the angular range for 360,180,90 or 45 (see Table 5). Fine-tuning of the angular range can be accomplished by adjusting the gain of the OPAMP buffer stage. The reference voltage for the Digital-to-Analog converter (DAC) can be taken internally from VDD5V / 2. In this mode, the output voltage is ratiometric to the supply voltage. Alternatively, an external DAC reference can be applied at pin DACref (#9). In this mode, the analog output is ratiometric to the external reference voltage. An on-chip diagnostic feature turns the analog output off in case of an error (broken supply or magnetic field out of range; see Table 3).
The DAC output can be accessed directly at pin #10 DACout. The addition of an OPAMP to the DAC output allows a variety of user configurable options, such as variable output voltage ranges and variable output voltage versus angle response. By adding an external transistor, the analog voltage output can be buffered to allow output currents up to hundred milliamperes or more. Furthermore, the OPAMP can be configured as constant current source.
As an OTP option, the DAC can be configured different output ranges:
to 2
a) 0......100% VDACref. The reference point may be either taken from VDD5V/2 or from the external DACref input. The 0...100% range allows easy replacement of potentiometers. Due to the nature of rail-to-rail outputs, the linearity will degrade at output voltages that are close to the supply rails. b) 10.....90% VDACref. This range allows better linearity, as the OPAMP is not driven to the rails. Furthermore, this mode allows failure detection, when the analog output voltage is outside of the normal operating range of 10...90%VDD, as in the case of broken supply or when the magnetic field is out of range and the analog output is turned off.
11.1 Analog output voltage modes
The Analog output voltage modes are programmable by OTP. Depending on the application, the analog output can be selected as rail-to-rail output or as clamped output with 10%-90% VDD5V. The output is ratiometric to the supply voltage (VDD5V), which can range from 3.0V to 5.5V. If the DAC reference is switched to an external reference (pin DACref), the output is ratiometric to the external reference.
11.1.1
Full Scale Mode
This output mode provides a ratiometric DAC output of (0% to 100%)x Vref *) , amplified by the OPAMP stage (default = internal 2x gain, see Figure 14)
Vref 100%
analog output voltage
Note: For simplification, Figure 8 describes a linear output voltage from rail to rail (0V to VDD). In practice, this is not feasible due to saturation effects of the OPAMP output driver transistors. The actual curve will be rounded towards the supply rails (as indicated in Figure 8).
angle 0 90 180 270 360
0V
Figure 8: Analog output, full scale mode (shown for 360mode)
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AS5043 Programmable 360 Magnetic Angle Encoder
Note: Figure 8 and are shown for 360 operation. See Table 5 (page 12) for further angular range programming options.
11.1.2
Diagnostic Output Mode
In an error case, the output voltage is in the grey area
Vref 100% 90% analog output voltage
normal operating area
10% 0% 0 90 180 270 360 angle
In Diagnostic Output Mode (see Figure 9) the analog output of the internal DAC ranges from 10% - 90% Vref *) . In an error case, either when the supply is interrupted or when the magnetic field is in the "red" range, (see Table 3) the output is switched to 0V and thus indicates the error condition.
Figure 9: Diagnostic Output Mode
It is possible to enable the analog output permanently (it will not be switched off even if the magnetic field is out of range). To enable this feature an OTP bit in the factory setting must be set. The corresponding bit is FS6. See application note AS5040-20 (Extended features of OTP programming) for further details. The application note is available for download at the austriamicrosystems website.
The analog and digital outputs will have the following conditions:
Status DAC output voltage SSI digital output
normal operation magnetic field out of range
10% - 90% Vref *) < 10% Vref *) , DAC output is switched to 0V < 10% VDD **)
#0 - #1023 (0-360), MagRngn = 1 #0 - #1023 (0-360) out of range is signaled in status bits: MagInc=MagDec=LIN=1, MagRngn= 0
broken positive power supply (VOUT pull down resistor at receiving side) broken power supply ground (VOUT pull down resistor at receiving side) broken positive power supply (VOUT pull up resistor at receiving side) broken power supply ground (VOUT pull up resistor at receiving side)
< 10% VDD **) with pull down resistor at DO (receiving side), all bits read by the SSI will be "0"-s, indicating a non-valid output
> 90% VDD **)
> 90% VDD **)
*) Vref = internal: 1/2 * VDD5V (pin #16) or external: VDACref (pin#9), depending on Ref_extEN bit in OTP (0=int., 1=ext.) **) VDD = positive supply voltage at receiving side (3.0 - 5.5V)
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AS5043 Programmable 360 Magnetic Angle Encoder
12 Programming the AS5043
After power-on, programming the AS5043 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 Analog Output Mode setting as shown in Table 5. Data must be valid at the rising edge of CLK (see Figure 10). Following this sequence, the voltage at pin Prog must be raised to the programming voltage VPROG (see Figure 11). 16 CLK pulses (tPROG) must be applied to program the fuses. To exit the programming mode, the chip must be reset by a power-on-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 (Figure 12) should not exceed 50mm (2 inches). To suppress eventual voltage spikes, a 10nF ceramic capacitor should be connected close to pins PROG 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 10). 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 19.7). To compensate for the voltage drop across the VPROG switching transistor, the applied programming voltage may be set slightly higher (7.5 8.0V, see Figure 12).
OTP Register Contents: CCW Counter Clockwise Bit ccw=0 - angular value increases with clockwise rotation ccw=1 - angular value increases with counterclockwise rotation Z [9:0]: Programmable Zero / Index Position FB_intEN: OPAMP gain setting: 0=external, 1=internal RefExtEN: DAC reference: 0=internal, 1=external Analog output span: 0=0-100%, 1=10-90%*VDD
ClampMd EN:
Output Range (OR0, OR1): Analog Output Range Selection [1:0] 00 = 360 01 = 180 10 = 90 11 = 45
Figure 10: Programming Access - OTP Write Cycle (section of Figure 11)
Figure 11: Complete OTP programming sequence Revision 1.4, 04-Apr-06 www.austriamicrosystems.com Page 9 of 26
AS5043 Programmable 360 Magnetic Angle Encoder
OTP: keep these wires as short as possible max. length = 2 inches (5cm)
AS5043 Demoboard
USB
IC1
16 VDD5V 15 VDD3V3 14 NC 13
connect to USB interface on PC
MagRngn
1 8 7 6 5 4 3 2 1 PROG CSN DO CLK 5VUSB VDD3V3 VSS VOUT_EXT 3 VPROG 2 + 1 10F VSS GND
Mode 2 CSn CLK 4 5 NC DO VSS
6 7 3
NC Vout FB
C
12 11 10 9
7.5 ... 8.0V only required for OTP programming
DACout DACref
Prog_DI 8
10n
GND
AS5043
+
1F only required for OTP programming
Figure 12: OTP programming hardware connection of AS5043 (shown with AS5043 demoboard)
12.1 Zero Position Programming
The AS5043 allows easy assembly of the system, as the actual angle of the magnet does not need to be considered. By OTP programming, any position can be assigned as the new permanent zero position with an accuracy of 0.35 (all modes). Using the same procedure, the AS5043 can be calibrated to assign a given output voltage to a given angle. With this approach, all offset errors (DAC + OPAMP) are also compensated for the calibrated position.
Essentially, for a given mechanical position, the angular measurement system is electrically rotated (by changing the Zero Position value in the OTP register), until the output matches the desired mechanical position.
The example in Figure 13 below shows a configuration for 5V supply voltage and 10%-90% output voltage range. It adjusted by Zero Position Programming to provide an analog output voltage of 2.0 Volts at an angle of 180. The slope of the curve may be further adjusted by changing the gain of the OPAMP output stage and by selecting the desired angular range (360/180/90/45).
VDD5V 5V analog output voltage 2V 0V
the output can be electrically rotated to match a given output voltage to any mechanical position
0
90
180
270
360
mechanical angle
Figure 13: Zero position programming (shown for 360 mode)
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AS5043 Programmable 360 Magnetic Angle Encoder
12.2 Analog Mode Programming
The analog output can be configured in many ways: It consists of three major building blocks, a digital range preselector, a 10-bit Digital-to-Analog-Converter (DAC) and an OP-AMP buffer stage.
In the default configuration (all OTP bits = 0), the analog output is set for 360 operation, internal DAC reference (VDD5V/2), external OPAMP gain, 0-100% ratiometric to VDD5V. Shown below is a typical example for a 0-360 range, 0-5V output. The complete application requires only one external component, a buffer capacitor at VDD3V3 and has only 3 connections VDD, VSS and Vout (connectors 1-3). Note: the default setting for the OPAMP feedback path is:FB_intEn=0=external. The external resistors Rf and Rg must be installed. In the programmed state (FB_intEn=1=internal), these resistors do not need to be installed as the feedback path is internal (Rf_int and Rg_int).
Magnetic field range alarm. Active low. Leave open or connect to VSS if not used
Mode pin. Default = open (low noise)
External DAC reference pin. Leave open or connect to VSS if not used
1
16
Connect pins 15 and 16 for VDD= 3.0-3.6V. Do NOT connect for VDD = 4.5-5.5V !
VDD
1
2 Mode DACref
9 VDD5V
AS5043
MagRngn
15 REF_extEN 1=ext 0 0 1 1 OR1 from DSP 360 180 90 45 OR0 0 1 0 1 Vref 10bit digital VDD5V / 2 0=int
10 DACout 0 - 100% VDD5V /2 10bit analog
DAC output pin. Leave open if not used
Range Selector
DAC
+
VOUT 12
ClampMdEN 0= 0-100% * Vref (def.) 1= 10-90% * Vref
0=ext 1=int
Rf_int 30k
Rf
FB_intEN Gain = 2x (int)
Rg_int 30k FB 11
CSn CLK DO 3 4 6
PROG 8
for OTP programming and alignment mode only. Leave open or connect to VSS if not used
NC NC 5 13
NC 14 VDD
VSS 7
OP-Amp feedback pin. Leave open if not used.
Test pins. Leave open
Digital serial interface, 10bit/360. Leave open if not used. CSn and CLK may also be tied to VSS if not used
Vout
0
Figure 14: analog output block diagram
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+ 1-10F Vout
LDO 3.3V
VDD3V3
2
RLmin = 4k7 CL <100pF
Rg
3
VSS
360angle
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AS5043 Programmable 360 Magnetic Angle Encoder
12.2.1
Angular range Selector :
The response curve for the analog output is linear for the selected range (45/90/180/360). In addition, the slope is mirrored at 180 for 45- and 90- modes and has a step response at 270 for the 180-mode. This allows the AS5043 to be used in a variety of applications. In these three modes, the output remains at Vout,max and Vout,min to avoid a sudden output change when the mechanical angle is rotated beyond the selected analog range. In 360-mode, a jitter between Vout,max and Vout,min at the 360 point is also prevented due to a hysteresis.
Note
The Angular Range selector allows a digital pre-selection of the angular range. The AS5043 can be configured for a full scale angular range of 45,90,180 or 360. In addition, the Output voltage versus angle response can be fine-tuned by setting the gain of the OP-AMP with external resistors and the maximum output voltage can be set in the DAC. The combination of these options allows to configure the operation range of the AS5043 for all angles up to 360 and output voltages up to 5.5V
Output Range1 Output Range0 Mode
3 6 0 a n g u la r ra n g e (d e fa u lt)
1023
default mode, analog resolution= 10bit (1024 steps) over 360
0
0
0 0 0 256 90 512 180 768 270 1 0 2 4 a n g le *) 360
analog step size: 1LSB = 0.35
1 8 0 a n g u la r ra n g e
1023
analog resolution= 10bit (1024 steps) over 180
0 1
0 0 0 256 90 512 180 768 270 1024 360
a n g le
Analog step size: 1LSB = 0.175
9 0 a n g u la r ra n g e
1023
1
0
0 0 0 256 90 512 180 768 270 1024 360
a n g le
analog resolution= 10bit (1024 steps) over 90 Analog step size: 1LSB = 0.088
4 5 a n g u la r ra n g e
511
analog resolution=
1 1
0 0 128 256 0 45 90 512 180 640 225 1024 360
a n g le
9 bit (512 steps) over 45 Analog step size: 1LSB = 0.088
*) Note: the resolution on the digital SSI interface is always 10bit (0.35/step) over 360, independent on analog mode
Table 5: Digital Range Selector programming options
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AS5043 Programmable 360 Magnetic Angle Encoder
12.3 Digital-to-Analog Converter (DAC)
The DAC has a resolution of 10bit (1024 steps) and can be configured for the following options
12.4 OP-AMP stage
The DAC output is buffered by a non-inverting Op-Amp stage. The amplifier is supplied by VDD5V (pin #16) and can hence provide output voltages up to 5V. By allowing access to the inverting input of the Op-Amp and with the addition of a few discrete components it can be configured in many ways, like high current buffer, current sink output, adjustable angle range, etc... Per default, the gain of the Op-Amp must be set by two external resistors (see Figure 14). Optionally, the fixed internal gain setting (2x) may be programmed by OTP, eliminating the need for external resistors.
Internal or external reference The default DAC reference is the voltage at pin #16 (VDD5V) divided by 2 (see Figure 14). Using this reference, a system that has an output voltage ratiometric to the supply voltage can be built.
Optionally, an external reference source, applied at pin#9 (DACref) can be used. This programming option is useful for applications requiring a precise output voltage that is independent of supply fluctuations, for current sink outputs or for applications with a dynamic reference, e.g. attenuation of audio signals.
12.4.1
0-100% or 10-90% full scale range The reference voltage for the DAC is buffered internally. The recommended range for the external reference voltage is 0.2V to (VDD3V3 -0.2)V. The DAC output voltage will be switched to 0V, when the magnetic field is out of range, when the MagInc and MagDec indicators are both =1 and the MagRngn-pin (#1) will go low.
Output Noise
The Noise level at the analog output depends on two states of the digital angular output: a) the digital angular output value is stable In this case, the output noise is the figure given as Vnoise in paragraph 19.3.6. Note that the noise level is given for the default gain of 2x For other gains, it must be scaled accordingly. the digital output is at the edge of a step In this case, the digital output may jitter between two adjacent values. The rate of jitter is specified as transition noise (parameter TN in paragraph 19.5). The resulting output noise is calculated by:
b)
The default full scale output voltage range is 0100%*VDD5V. Due to limitations in the output stage of an OP-Amp buffer, it cannot drive the output voltage from 0-100% rail-to-rail. Without load, the minimum output voltage at 0 will be a few millivolts higher than 0V and the maximum output voltage will be slightly lower than VDD5V . With increasing load, the voltage drops will increase accordingly. As a programming option, an output range of 1090%*VDD5V can be selected. In this mode, there is no saturation at the upper and lower output voltage limits like in the 0-100% mode and it allows failure detection as the output voltage will be outside the 10-90% limits, when the magnetic field is in the "red" range (Vout=0V, see Table 3) or when the supply to the chip is interrupted (Vout=0V or VDD5V). The unbuffered output of the DAC is accessible at pin #10 (DACout). This output must not be loaded.
Vnoise ,Vout =
where: Vnoise, Vout TN VDD5V Vnoise,OPAMP
TN VDD5V + Vnoise ,OPAMP 360
= noise level at pin Vout in Vrms = transition noise (see 19.5 in rms) = Supply voltage VDD5V in V = noise level of OPAMP (paragraph 19.3.6) in Vrms
12.5 Application Examples
See Application Note AN5043-10 for AS5043 Application Examples.
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AS5043 Programmable 360 Magnetic Angle Encoder
13 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. In order to verify the quality of the programmed bits, 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 AS5043 in Analog Readback Mode, a digital sequence must be applied to pins CSn, PROG and CLK as shown in Figure 15. The digital level for this pin depends on the supply configuration (3.3V or 5V; see section 7, page 4). 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 15). 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 15: Output Range OR0 and -1 , ClampMdEn, RefExtEn, FB_IntEn, Z0...Z9, ccw) During analog readback, the capacitor at pin PROG (see Figure 12) should be removed 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 16 th clock (after reading bit "ccw"), the chip must be reset by disconnecting the power supply.
P ro g E N CSn
O u tp E N
A n a log R e a d b a ck D a ta a t P R O G
P o w e r-o n R e se t; cyc le su p p ly
V re f PROG
In te rn a l te st b it d ig ita l
V p ro g ra m m e d OR0 OR1 1
C la m p R e fE xt MdEN EN
V u n p ro g ra m m e d Z 5
Z6
Z7
Z8
Z9
ccw 16
P ro g c h a n g es to O u tp ut
CLK t L o a d P ro g
C L K A re a d
Figure 15:Analog OTP Register Read
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AS5043 Programmable 360 Magnetic Angle Encoder
14 Alignment Mode
The alignment mode simplifies centering the magnet over the chip to gain maximum accuracy and XY-alignment tolerance. This electrical centering method allows a wider XYalignment tolerance (0.485mm radius) than mechanical centering (0.25mm radius) as it eliminates the placement tolerance of the die within the IC package (+/- 0.235mm). Alignment mode can be enabled with the falling edge of CSn while PROG = logic high (Figure 16). 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. 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 MagInc and MagDec indicators will be = 1 when the alignment mode reading is < 32. At the same time, hardware pin MagRngn (#1) will be pulled to VSS. The Alignment mode can be reset to normal operation mode by a power-on-reset (cycle power supply) or by a falling edge of CSn with PROG=low (see Figure 17).
15 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.
The magnet's field strength perpendicular to the die surface 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 18).
typ. 6mm diameter
N
S
Magnet axis R1
Magnet axis
Vertical field component
R1 concentric circle; radius 1.1mm Vertical field component
PROG
AlignMode enable
CSn
Read-out via SSI
Bv
(45...75mT)
0
360
360
2s 2s min. min.
Figure 18: Typical magnet and magnetic field distribution Figure 16: Enabling the alignment mode
PROG
exit AlignMode
CSn
Read-out via SSI
Figure 17:Exiting alignment mode
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AS5043 Programmable 360 Magnetic Angle Encoder Figure 20: Vertical placement of the magnet
15.1 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 IC package as shown in Figure 19:
3.9 mm
1
16 Simulation Modelling
3.9 mm 0.235mm 1
3.9 mm
2.433 mm Defined center
2.433
mm X1
0.235mm
Y1 X2
Rd
2.433 mm Area of recommended maximum magnet misalignment
Y2
Figure 19: Defined IC center and magnet displacement radius
AS5043 die
Center of die
Radius of circular Hall sensor array: 1.1mm radius
15.1.1
Magnet Placement:
Figure 21: Arrangement of Hall sensor array on chip (principle)
The magnet's center axis should be aligned within a displacement radius Rd of 0.25mm from the defined center of the IC with reference to the edge of pin #1 (see Figure 19). This radius includes the placement tolerance of the chip within the SSOP-16 package (+/- 0.235mm). The displacement radius Rd is 0.485mm with reference to the center of the chip (see section 14: Alignment Mode). The vertical distance should be chosen such that the magnetic field on the die surface is within the specified limits (see Figure 18). The typical distance "z" between the magnet and the package surface is 0.5mm to 1.8mm with the recommended magnet (6mm x 3mm). Larger gaps are possible, as long as the required magnetic field strength stays within the defined limits. A magnetic field outside the specified range may still produce usable results, but the out-of-range condition will be indicated by MagRngn (pin 1), which will be pulled low. At this condition, the angular data is still available over the digital serial interface (SSI), but the analog output will be turned off.
With reference to Figure 21, a diametrically magnetized permanent magnet is placed above or below the surface of the AS5043. 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:
= arctan
(Y 1 - Y 2) 0.5 ( X 1 - X 2)
N
Die surface
S
Package surface
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 AS5043. Placement tolerances of
z
0.576mm 0.1mm 1.282mm 0.15mm
the die within the package are 0.235mm in X and Y direction, using a reference point of the edge of pin #1 (Figure 21) 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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AS5043 Programmable 360 Magnetic Angle Encoder
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.
a broken power supply to the AS5043, the pull-up resistor (~10k) must be connected to the positive supply at pin 16 (VDD5V). .
18 Angular Output tolerances
18.1 Accuracy; digital outputs
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 23). Misalignment of the magnet further reduces the accuracy. Figure 22 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 23 is repeated and the accuracy (Errmax - Errmin)/2 (e.g. 0.25 in Figure 23) is entered as the Z-axis in the 3D-graph.
The recommended differential input range of the 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. 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.
17 Failure Diagnostics
The AS5043 also offers several diagnostic and failure detection features:
17.1 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: Pin #1 (MagRngn) is a logical NAND-ed combination of the MagInc and MagDec status bits. It is an open-drain output and will be turned on (= low with external pull-up resistor) when the magnetic field is out of range. By hardware: Pin #12 (Vout) is the analog output of the DAC and OP-Amp. The analog output will be 0V, when the magnetic field is out of range (all analog modes).
18.2 Accuracy; analog output
The analog output has the same accuracy as the digital output with the addition of the nonlinearities of the DAC and the OPAMP (+/-1LSB; see Table 5 and 19.3.5).
Linearity Error over XY-misalignment []
17.2 Power supply failure detection
By software: If the power supply to the AS5043 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 MagRngn pin is an open drain output and requires an external pull-up resistor. In normal operation, this pin is high ohmic and the output is high. In a failure case, either when the magnetic field is out of range or the power supply is missing, this output will become low. To ensure an adequate low level in case of
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6
5 4 3 2 1 0 1000 800 600
800 500 200 -100 -400 400 200 -700 -200 -400 -600 -1000 -800 -1000 x
y
Figure 22: Example of linearity error over XY misalignment
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AS5043 Programmable 360 Magnetic Angle Encoder
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 these measurement was a cylindrical NdFeB (Bomatec(R) BMN-35H) magnet with 6mm diameter and 2.5mm in height.
linearity
0.5 0.4 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 -0.4 -0.5
error
with
centered
magnet
transition noise
Err max
1
55 109 163 217 271 325 379 433 487 541 595 649 703 757 811 865 919 973
Err min
Figure 23: Example of linearity error over 360
18.3 Transition Noise
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 0.12 degrees rms (1 sigma) *1 in fast mode (pin MODE = high) and 0.06 degrees rms (1 sigma) *1 in slow mode (pin MODE = low or open). These values are 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 applying an averaging of readings. An averaging of 4 readings will reduce the transition noise by 6dB or 50%. analog output: Ideally, the analog output should have a jitter that is less than one digit. In 360 mode, both fast or slow mode may be selected for adequate low jitter.
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In 180, 90 or 45 mode, where the step sizes are smaller, slow mode should be selected to reduce the output jitter.
*1
: statistically, 1 sigma represents 68.27% of readings, 3 sigma represents 99.73% of readings.
18.4 High Speed Operation
18.4.1 Sampling rate
The AS5043 samples the angular value at a rate of 10.42k samples per second (ksps) in fast mode and 2.61ksps in slow mode. Consequently, a new reading is performed each 96s. (fast mode) or 384s (slow mode). At a stationary position of the magnet, this sampling rate creates no additional error.
Absolute Mode: With the given sampling rates, the number of samples (n) per turn for a magnet rotating at high speed can be calculated by
n= n=
60 for fast mode rpm 96 s 60 for slow mode rpm 384 s
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AS5043 Programmable 360 Magnetic Angle Encoder
In practice, there is no upper speed limit. The only restriction is that there will be fewer samples per revolution as the speed increases. Regardless of the rotational speed, the absolute angular value is always sampled at the highest resolution.
Internal timing tolerance
The AS5043 does not require an external ceramic resonator or quartz. All internal clock timings for the AS5043 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:
Fast Mode (pin Mode = 1)
Slow Mode (pin Mode = 0 or open)
610rpm = 1024 samples / turn 1220rpm = 512 samples / turn 2441rpm = 256 samples / turn etc...
610rpm = 256 samples / turn 1220rpm = 128 samples / turn 2441rpm = 64 samples / turn etc...
18.5.2
absolute output; SSI interface:
A new angular value is updated every 96s +/- 5% (Mode = 1) or 384s +/- 5% (Mode = 0 or open)
Table 6: Speed performance
18.5 Output delays
The propagation delay is the delay between the time that the sample is taken until it is available as angular data. This delay is 96s in fast mode (pin Mode = high) and 384s in slow mode (pin Mode = low or open) The analog output produces no further delay, the output voltage will be updated as soon as it is available. Using the SSI interface for 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 AS5043.
18.6 Temperature
18.6.1 Magnetic temperature coefficient
One of the major benefits of the AS5043 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 AS5043 automatically compensates for the varying magnetic field strength over temperature. The magnet's temperature drift does not need to be considered, as the AS5043 operates with magnetic field strengths from 45...75mT.
18.5.1
Angular error caused by propagation delay
A rotating magnet will cause an angular error caused by the propagation delay. This error increases linearly with speed:
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 AS5043 can compensate for this temperature related field strength change automatically, no user adjustment is required.
e sampling (deg) = 6 rpm pr.delay
where esampling = angular error [] rpm = rotating speed [rpm] prop.delay = propagation delay [seconds]
18.6.2
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.
Note: since the propagation delay is known, it can be automatically compensated by the control unit processing the data from the AS5043.
18.6.3
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.
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AS5043 Programmable 360 Magnetic Angle Encoder
19 Electrical Characteristics
19.1 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 Symbol Min Max Unit Note
DC supply voltage
VDD5V VDD3V3
-0.3
7 5
V V
Pin VDD5V Pin VDD3V3 Pins MagRngn, Mode, CSn, CLK, DO, DACout, FB, Vout
-0.3 Input pin voltage Vin -0.3 -0.3 Input current (latchup immunity) Electrostatic discharge Storage temperature Body temperature (Lead-free package) Humidity non-condensing Iscr ESD Tstrg TBody H 5 -100 2 -55
VDD5V +0.3 5 7.5 100 mA kV 125 260 85 C C % V
Pin DACref Pin PROG_DI 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"
19.2 Operating Conditions
Parameter Symbol Min Typ Max Unit Note
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
Tamb Isupp VDD5V VDD3V3 VDD5V VDD3V3
-40 16 4.5 3.0 3.0 3.0 5.0 3.3 3.3 3.3
125 20 5.5 3.6 3.6 3.6
C mA V V V V
-40F...+257F
5V Operation 3.3V Operation (pin VDD5V and VDD3V3 connected)
19.3 DC Characteristics for Digital Inputs and Outputs
19.3.1 CMOS Schmitt-Trigger Inputs: CLK, CSn (internal Pull-up), Mode (internal Pull-down)
Symbol Min Max Unit Note
(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 Pull-down high level input current
VIH VIL VIon- VIoff ILEAK IiL IiH
0.7 * VDD5V 0.3 * VDD5V 1 -1 -30 30 1 -100 100
V V V
Normal operation
Pin CLK, VDD5V = 5.0V A Pin CSn, VDD5V= 5.0V Pin Mode, VDD5V= 5.0V
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AS5043 Programmable 360 Magnetic Angle Encoder
19.3.2
CMOS input : 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 Symbol Min Max Unit Note
High level input voltage High level input voltage Low level input voltage Pull-down high level input current
VIH VPROG VIL IiL
0.7 * VDD5V
5
V V V A VDD5V: 5.5V During programming
See "programming conditions" 0.3 * VDD5V 100
19.3.3
CMOS Output Open Drain: MagRngn
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter Symbol Min Max Unit Note
Low level output voltage Output current Open drain leakage current
VOL IO IOZ
VSS+0.4 4 2 1
V mA A VDD5V: 4.5V VDD5V: 3V
19.3.4
Tristate CMOS Output: DO
Symbol Min Max Unit Note
(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
VOH VOL IO
VDD5V -0.5 VSS+0.4 4 2
V V mA mA A VDD5V: 4.5V VDD5V: 3V
Tri-state leakage current
IOZ
1
19.3.5
Resolution
Digital-to-Analog Converter
Symbol Min Typ Max Unit Note OTP setting
Parameter
10 VOUTM1 VOUTM2 0 0.10 *Vref Vref 0.90 *Vref 8
bit V V k 0......100% Vref (default) 10.....90% Vref Unbuffered Pin DACout (#10) DACref = external: Pin: DACref (#9) DACref = internal Non-Linearity of DAC and OPAMP; -40....+125C, For all analog modes: 1LSB = (see Table 5) 1 LSB LSB All analog modes At 360-0 transition, 360 mode only OR1,OR0 = 00 (default) RefExt EN = 1 RefExtEn = 0 (default) ClampMdEn = 0 (default) ClampMdEn = 1
Output Range
Output resistance
ROut,DAC
External DAC reference VDACref input voltage range
0.2
VDD3V3 - 0.2 VDD5V / 2
V V LSB LSB
Integral Non-Linearity Differential Non-Linearity
INLDAC DNLDAC
+/- 1 +/- 1/2
Analog output hysteresis
Hyst 2
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AS5043 Programmable 360 Magnetic Angle Encoder
19.3.6
OPAMP output stage
Symbol Min Typ Max Unit Note
Parameter
Power Supply Range Parallel Load Capacitance Parallel Load Resistance Open Loop Gain Offset Voltage RTI Output Range Low Output Range High current capability sink current capability source Output noise
VDD5V CL RL A0 VosOP VoutL VoutH Isink Isource Vnoise
3.0
5.5 100
V pF k 3.3V operation
4.7 92 -5 130 144 5
dB mV 3 sigma Linear range of analog output Permanent short Vout to VDD5V Permanent short Vout to VSS circuit circuit current: current:
0.05 * VDD5V V 0.95 * VDD5V 4.8 4.6 160 220 2 50 66 490 V mA mA Vrms
Over full temperature range; BW= 1Hz...10MHz,Gain = 2x Internal: FB_int EN = 1
OPAMP gain (non-inverting)
Gain
1
4
Times
FB_int EN = 0 With external resistors, pins Vout [#12] and FB [#11]:
19.4 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 Symbol Min Typ Max Unit Note
Diameter Magnetic input field amplitude Magnetic offset Field non-linearity
dmag Bpk Boff
4 45 75 5 5
mm mT mT % Hz
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 Absolute mode: 600 rpm @ readout of 1024 positions (see table 6) Incremental mode: no missing pulses at rotational speeds of up to 10,000 rpm (see table 6) Max. offset between defined device center and magnet axis NdFeB (Neodymium Iron Boron) SmCo (Samarium Cobalt)
Input frequency (rotational speed of magnet)
fmag_abs
10
fmag_inc Disp -0.12 -0.035
166 0.25
Hz mm
Displacement radius Recommended magnet material and temperature drift
%/K
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AS5043 Programmable 360 Magnetic Angle Encoder
19.5 Electrical System Specifications
(operating conditions: Tamb = -40 to +125C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted)
Parameter Symbol Min Typ Max Unit Note
Resolution
*
RES INLopt
10 0.5
bit deg
0.352 deg Maximum error with respect to the best line fit. Verified at optimum magnet placement, Tamb =25 C. Maximum error with respect to the best line fit. Verified at optimum magnet placement , Tamb = -40 to +125C Best line fit = (Errmax - Errmin) / 2
Integral non-linearity (optimum) *
Integral non-linearity (optimum) *
INLtemp
0.9
deg
Integral non-linearity
*
INL
1.4
deg
Over displacement tolerance with 6mm diameter magnet, Tamb = -40 to +125C 10bit, no missing codes 1 sigma, fast mode (pin MODE = 1) 1 sigma, slow mode (pin MODE=0 or open) DC supply voltage 3.3V (VDD3V3) DC supply voltage 3.3V (VDD3V3) fast mode (pin MODE=1)
Differential non-linearity*
DNL
0.176 0.06 0.03 1,37 1.08 2.2 1.9 2.9 2.6 20
deg Deg RMS V V
Transition noise* Power-on reset thresholds On voltage; 300mV typ. hysteresis Off voltage; 300mV typ. hysteresis Power-up time, Until offset compensation finished, OCF = 1, Angular Data valid System propagation delay absolute output : delay of ADC and DSP Internal sampling rate for absolute output: Internal sampling rate for absolute output Read-out frequency
TN
Von Voff
tPwrUp 80 96 tdelay 2.48 2.35 9.90 9.38 2.61 2.61 10.42 10.42 384 2.74 2.87 10.94 11.46 1
ms slow mode (pin MODE=0 or open) fast mode (pin MODE=1) s slow mode (pin MODE=0 or open) Tamb = 25C, slow mode (pin MODE=0 or open) kHz Tamb = -40 to +125C, slow mode (pin MODE=0 or open) Tamb = 25C, fast mode (pin MODE = 1) kHz MHz Tamb = -40 to +125C, : fast mode (pin MODE = 1) Max. clock frequency to read out serial data
fS,mode0
fS,mode1 CLK
*)digital interface
1023
10bit code
Actual curve
2 1 0
1023 TN DNL+1LSB INL 0.35 512 Ideal curve
512
0 0 180
Figure 24: Integral and differential Non-Linearity (example) Revision 1.4, 04-Apr-06 www.austriamicrosystems.com
360
[degrees]
Page 23 of 26
AS5043 Programmable 360 Magnetic Angle Encoder
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. Transition Noise (TN) is the repeatability of an indicated position.
19.6 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
Symbol
Min
Typ
Max
Unit
Note
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
t DO active tCLK FE T CLK / 2 t DO valid t DO tristate t CSn fCLK 500 >0 500 500
100
ns ns ns
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
375 100
ns ns ns
1
MHz
19.7 Programming Conditions
(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 Rise time of VPROG before CLK PROG Hold time of VPROG after CLK PROG Write data - programming CLK PROG CLK pulse width Hold time programming of Vprog after Symbol t Prog enable t Data in t Data in valid t Load PROG t PrgR t PrgH CLK PROG t PROG t PROG
finished
Min 2 2 250 3 0 0
Typ
Max
Unit s s ns s s
Note Time between rising edge at Prog pin and rising edge of CSn
Write data at the rising edge of CLKPROG
5 250
s kHz s s During programming; 16 clock cycles Programmed data is available after next power-on Must be switched off after zapping Line must be discharged to this level During programming Analog readback mode VRef-VPROG during analog readback mode (see 13)
1.8 2 7.3 0
2
2.2
Programming voltage Programming voltage off level Programming current Analog read CLK Programmed zener voltage (log.1)
Unprogrammed zener voltage (log. 0)
V PROG V ProgOff I PROG
CLKAread Vprogrammed Vunprogrammed
7.4
7.5 1 130
100 100
V V mA
kHz mV V
1
Revision 1.4, 04-Apr-06
www.austriamicrosystems.com
Page 24 of 26
AS5043 Programmable 360 Magnetic Angle Encoder
20 Package Drawings and Markings
16-Lead Shrink Small Outline Package SSOP-16
AYWWIZZ AS5043
Dimensions mm Symbol Min Typ Max inch Min Typ Max
1.1.1
Marking: AYWWIZZ
A: Pb-Free Identifier Y: Last Digit of Manufacturing Year WW: Manufacturing Week I: Plant Identifier ZZ: Traceability Code
A A1 A2 b c D E E1 e K L
1.73 0.05 1.68 0.25 0.09 6.07 7.65 5.2 0.65 0 0.63
1.86 0.13 1.73 0.315 6.20 7.8 5.3 0.75
1.99 0.21 1.78 0.38 0.20 6.33 7.9 5.38 8 0.95
.068 .002 .066 .010 .004 .239 .301 .205 .0256 0 .025
.073 .005 .068 .012 .244 .307 .209 .030
.078 .008 .070 .015 .008 .249 .311 .212 8 .037
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
21 Packing Options
Delivery: Tape and Reel (1 reel = 2000 devices) Tubes (1 box = 100 tubes a 77 devices)
Order # AS5043
for delivery in tubes
Order # AS5043TR for delivery in tape and reel
Revision 1.4, 04-Apr-06
www.austriamicrosystems.com
Page 25 of 26
AS5043 Programmable 360 Magnetic Angle Encoder
22 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
23 Revision History
Revision Date Description
1.4
Apr. 04, 2006
Update Programming Sequence Figure 11; Update Prog. Conditions 19.7 Include new OTP feature: permanent enabling of analog output (see 11.1.2). Update added features for Date Codes A534xx and higher: Clamping levels: 10%/90% VDD, default OPAMP gain = external, red/yellow/green Magnetic field indicator, exit alignment mode by s/w, falling edge on analog response curve on 45 and 90 modes, jitter-free transition 360/0 in analog mode. Update propagation delay and thermal resistance of IC package
1.3
Sep. 27, 2005
1.2 1.1 1.0
April 11, 2005 Feb. 18.2005 Dec. 7, 2004
Add description for Analog modes and Programming Update pin assignment and operating modes initial revision
24 Contact
24.1 Headquarters
austriamicrosystems AG A 8141 Schloss Premstatten, Austria Phone: Fax: +43 3136 500 0 +43 3136 525 01
industry.medical@austriamicrosystems.com www.austriamicrosystems.com
25 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) 2006 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 1.4, 04-Apr-06 www.austriamicrosystems.com Page 26 of 26

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