austriamicrosystems AG is now ams AG The technical content of this austriamicrosystems datasheet is still valid. Contact information: Headquarters: ams AG Tobelbaderstrasse 30 8141 Unterpremstaetten, Austria Tel: +43 (0) 3136 500 0 e-Mail: [email protected] Please visit our website at www.ams.com AS5048A/AS5048B Datasheet am lc s on A te G nt st il lv al id Magnetic Rotary Encoder 14-bit Angular Position Sensor General Description The AS5048 is an easy to use 360° angle position sensor with a 14-bit high resolution output. The maximum system accuracy is 0.05° assuming linearization and averaging is done by the external microcontroller. The IC measures the absolute position of the magnet’s rotation angle and consists of Hall sensors, analog digital converter and digital signal processing. The zero position can be programmed via SPI or I²C command. Therefore no programmer is needed anymore. This simplifies the assembly of the complete system because the zero position of the magnet does not need to be mechanically aligned. This helps developers to shorten their developing time. The sensor tolerates misalignment, air gap variations, temperature variations and as well external magnetic fields. This robustness and wide temperature range (-40°C up to +150°C) of the AS5048 makes the IC ideal for rotation angle sensing in harsh industrial and medical environments. Several AS5048 ICs can be connected in daisy chain for serial data read out. The absolute position information of the magnet is directly accessible over a PWM output and can be read out over a standard SPI or a high speed I²C interface. AS5048A has a SPI interface, AS5048B I2C interface. Both devices offer a PWM output. An internal voltage regulator allows the AS5048 to operate at either 3.3 V or 5 V supplies. Applications Key Features & Benefits • Robotic joint position detection • Industrial motor position control • Medical robots and fitness equipment Block Diagram ch • ca • • 360° contactless angle position sensor Standard SPI or high speed I²C interface Pulse width modulated output (PWM) Simple programmable zero position via SPI or I²C command No programmer needed 14-bit full scale resolution 0.0219°/LSB Angle accuracy 0.05°after system linearization and averaging Daisy chain capability Tolerant to air gap variations magnetic field input range: 30mT – 70mT -40°C to +150°C ambient temperature range 3.3V / 5V compliant 14-pin TSSOP package (5x6.4mm) ni • • • • Te • • • • • Revision 1.3 www.austriamicrosystems.com Page 1 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor al id Contents GENERAL DESCRIPTION .................................................................................................................. 1 PIN CONFIGURATION ................................................................................................................. 5 1.1 2 P IN D ESCRIPTION ........................................................................................................................ 5 am lc s on A te G nt st il 1 lv K EY F EATURES & B ENEFITS .................................................................................................................. 1 A PPLICATIONS ..................................................................................................................................... 1 B LOCK D IAGRAM ................................................................................................................................. 1 ELECTRICAL CHARACTERISTICS ............................................................................................ 6 2.1 2.2 2.3 2.4 2.5 A BSOLUTE M AXIMUM R ATINGS .................................................................................................... 6 O PERATING C ONDITIONS ............................................................................................................. 7 DC/AC C HARACTERISTICS FOR DIGITAL INPUTS AND OUTPUTS ....................................................... 7 E LECTRICAL S YSTEM S PECIFICATIONS .......................................................................................... 8 G LOBAL T IMING C ONDITIONS ...................................................................................................... 8 3 FUNCTIONAL DESCRIPTION ...................................................................................................... 9 4 OPERATION .................................................................................................................................. 9 Te ch ni ca 4.1 S UPPLY V OLTAGE C ONFIGURATION .............................................................................................. 9 4.2 SPI I NTERFACE ......................................................................................................................... 10 4.2.1 SPI Interface Signals (4-Wire Mode, Wire_mode = 1) .......................................................... 10 4.2.2 SPI Timing ......................................................................................................................... 11 4.2.3 SPI Connection to the Host UC ........................................................................................... 12 4.2.4 SPI Communication Command Package .............................................................................. 13 4.2.5 Read Package (Value Read from AS5048A) ......................................................................... 14 4.2.6 Write Data Package (Value Written to AS5048A) ................................................................. 14 4.2.7 Register Map SPI ............................................................................................................... 15 4.2.8 SPI Interface Commands .................................................................................................... 16 4.3 I²C INTERFACE .......................................................................................................................... 19 4.3.1 I²C Electrical Specification ................................................................................................ 19 4.3.2 I²C Timing ......................................................................................................................... 20 4.3.3 Register Table .................................................................................................................... 21 4.3.4 I²C Slave address ............................................................................................................... 22 4.4 PWM INTERFACE ...................................................................................................................... 22 5 PACKAGE DRAWINGS AND MARKINGS ................................................................................. 23 5.1.1 6 Assembly Lot Code ............................................................................................................. 23 APPLICATION INFORMATION ................................................................................................. 25 6.1 P ROGRAMMING OF THE AS5048 ................................................................................................. 25 6.1.1 Programming of the zero position ....................................................................................... 25 6.1.2 Programming sequence with verification ............................................................................. 25 6.2 D IAGNOSTIC FUNCTIONS OF THE AS5048 .................................................................................... 25 Revision 1.3 www.austriamicrosystems.com Page 2 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor C HOOSING THE P ROPER M AGNET ............................................................................................... 26 P HYSICAL P LACEMENT OF THE M AGNET ..................................................................................... 27 M AGNET P LACEMENT ................................................................................................................ 27 al id 6.3 6.4 6.5 7 ORDERING INFORMATION ...................................................................................................... 28 8 REVISION HISTORY .................................................................................................................. 28 9 COPYRIGHTS .............................................................................................................................. 29 lv 10 DISCLAIMER .............................................................................................................................. 29 am lc s on A te G nt st il List of Figures ca F IGURE 1: P IN CONFIGURATION TSSOP14 ................................................................................................. 5 F IGURE 2: C ONNECTIONS FOR 5V AND 3.3V SUPPLY VOLTAGES .................................................................. 9 F IGURE 3 SPI C ONNECTION AS5048A WITH U C ...................................................................................... 10 F IGURE 4 SPI C OMMAND /R ESPONSE D ATA F LOW .................................................................................... 10 F IGURE 5 SPI T IMING D IAGRAM ............................................................................................................. 11 F IGURE 6 S INGLE S LAVE M ODE .............................................................................................................. 12 F IGURE 7 M ULTIPLE S LAVE , N +3 W IRE (S EPARATE C HIP S ELECT ) ............................................................. 12 F IGURE 8 D AISY C HAIN , 4 W IRE ............................................................................................................ 13 F IGURE 9 READ C OMMAND ................................................................................................................... 16 F IGURE 10 WRITE C OMMAND ............................................................................................................... 16 F IGURE 11 CLEAR ERROR FLAG C OMMAND ........................................................................................ 17 F IGURE 12 NOP C OMMAND ................................................................................................................... 18 F IGURE 13 S LAVE ADDRESS CONSTRUCTION ............................................................................................ 22 F IGURE 14 PWM F ORMAT ...................................................................................................................... 23 F IGURE 15 P ACKAGE M ARKING .............................................................................................................. 23 F IGURE 16: T YPICAL MAGNET AND MAGNETIC FLUX DISTRIBUTION ........................................................... 26 F IGURE 17: D EFINED CHIP CENTER AND MAGNET DISPLACEMENT RADIUS .................................................. 27 F IGURE 18: V ERTICAL PLACEMENT OF THE MAGNET ................................................................................. 27 1: P IN DESCRIPTION TSSOP14 ....................................................................................................... 5 2 A BSOLUTE M AXIMUM R ATINGS .................................................................................................. 6 3: O PERATING C ONDITION ............................................................................................................. 7 4:DC/AC CHARACTERISTICS ......................................................................................................... 7 5 S YSTEM SPECIFICATION .............................................................................................................. 8 6 G LOBAL TIMING CONDITIONS ...................................................................................................... 8 7 SPI T IMING C HARACTERISTICS ................................................................................................. 11 8 SPI C OMMAND P ACKAGE ......................................................................................................... 13 9 SPI READ PACKAGE .................................................................................................................. 14 10 SPI WRITE DATA PACKAGE ...................................................................................................... 14 11 SPI REGISTER MAP ................................................................................................................. 15 Te ch T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE ni List of Tables Revision 1.3 www.austriamicrosystems.com Page 3 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor al id 12 C LEAR E RROR F LAG C OMMAND .............................................................................................. 17 13 NOP C OMMAND ..................................................................................................................... 18 14 I²C E LECTICAL S PECIFICATION ............................................................................................... 19 15 I²C T IMING ............................................................................................................................ 20 16 R EGISTER M AP I2C ................................................................................................................ 21 17 PWM P ERIOD AND RESOLUTION .............................................................................................. 23 18: O RDERING I NFORMATION ...................................................................................................... 28 Te ch ni ca am lc s on A te G nt st il lv T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE T ABLE Revision 1.3 www.austriamicrosystems.com Page 4 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor Pin Configuration am lc s on A te G nt st il lv al id 1 Figure 1: Pin configuration TSSOP14 1.1 Pin Pin Description AS5048A Type Description AS5048B Type Description 1 CSn DI_ST SPI chip select - active low SDA 2 CLK DI_ST SPI clock input SCL DI_ST I2C clock input 3 MISO A2 DI_ST I2C address selection pin 3 4 MOSI DI_ST A1 DI_ST I2C address selection pin 4 5 TEST AIO Test pin, see Note 6 TEST AIO Test pin, see Note 7 TEST AIO Test pin, see Note 8 TEST AIO Test pin, see Note 9 TEST AIO Test pin, see Note AIO Test pin, see Note TEST 11 VDD5V 12 VDD3V GND 14 PWM S DO S AIO DI_ST DO DIO _ST DIO _OD Te ch PIN Types: S Same as AS5048A Positive Supply Voltage, 3.0 to 5.5 V 3.3V Regulator output; internally regulated from VDD. Connect to VDD for 3V supply voltage. 10µF capacitor to GND required in 5V operation mode Negative Supply Voltage (GND) Pulse Width Modulation output ni 13 S SPI master out/slave in ca 10 DIO_ST SPI master in/slave out DIO_OD Data pin I2C interface ... ... … ... ... ... Table 1: Pin description TSSOP14 supply pad analog I/O digital input with schmitt trigger digital output – push-pull digital I/O with schmitt trigger in the input path digital I/O with open drain output Note: Pin 5, 6, 7, 8, 9, 10 should be grounded to GND. Revision 1.3 www.austriamicrosystems.com Page 5 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 2 Absolute Maximum Ratings al id 2.1 Electrical Characteristics Symbol Min Max Unit DC supply voltage at VDD pin VDD5V -0.3 7 V DC voltage at VDD3V pin VDD3V -0.3 5 V GND -0.3 0.3 V VDD+0.3 V 100 mA Norm: Jedec 78 Norm: MIL 883 E method 3015 DC voltage at GND pin Input pin voltage V_in Input current (latchup immunity) I_scr Electrostatic discharge ESD +/-2 kV P_t 150 mW 150 °C Total power dissipation (all supplies and outputs) Storage temperature T_strg Package body temperature Humidity non-condensing -100 -55 T_body H MSL 5 260 °C 85 % 3 ca Moisture Sensitive Level Note am lc s on A te G nt st il Parameter lv 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. The reflow peak soldering temperature (body temperature)specified is in accordance with IPC/JEDEC JSTD-020 “Moisture Solid State Surface Mount Devices”. The lead finish from Pb-free leaded packages is matte tin (100% Sn) Represents a maximum floor life time of 168h Te ch ni Table 2 Absolute Maximum Ratings Revision 1.3 www.austriamicrosystems.com Page 6 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 2.2 Operating Conditions Symbol Min Max Unit Positive supply voltage VDD5V 4.5 5.5 V 5V Operation via LDO VDD3V 3 3.6 V LDO output voltage VDDCORE 3 3.6 V GND 0 0 V T_amb -40 150 °C 15 mA Ambient temperature Supply Current Only for 5V operation. T_amb_max for 3V is 125°C am lc s on A te G nt st il Negative supply voltage lv Parameter Positive core supply voltage Note al id All in this specification defined tolerances for external components need to be assured over the whole operation conditions range and also over lifetime. I_sup Table 3: Operating Condition 2.3 DC/AC Characteristics for digital inputs and outputs Parameter Symbol Min CMOS digital input with schmitt trigger: CSn, CLK, MOSI High level input voltage V_IH 0.7 * VDD5V Low level input voltage Input leakage current CMOS output: PWM, MISO High level output voltage Capacitive load Unit V l_LEAK 1 µA V_OH VDD5V-0.5 V V_OL GND+0.4 V C_L 50 pF 4 mA I_OUT Note V 0.3 * VDD5V Table 4:DC/AC characteristics Te ch ni Output current Max V_IL ca Low level output voltage Typ Revision 1.3 www.austriamicrosystems.com Page 7 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor VDD5V = 5V, TAmbient = -40 to +150°C unless noted otherwise Symbol Min Typ Max Unit Magnetic input field Bz 30 50 70 mT Output sampling rate fsample 10.2 11.25 12.4 kHz Output Resolution RES Sensor output noise Noise 14 Bit 0.06 Deg Note 2.73LSB@14bit, rms value am lc s on A te G nt st il Parameter al id Electrical System Specifications lv 2.4 System propagation delay tprop 90.7 100 110.2 µs PWM frequency fPWM 0.907 1 1.102 kHz ±0.4 Deg Assuming 8 mm diameter of magnet Deg Assuming 8 mm diameter of magnet and 500 um displacement in x and y Assuming 8 mm diameter of magnet and 500 um displacement in x and y Non-linearity optimum placement of magnet INLOPT Non-linearity @displacement of magnet INLDIS Non-linearity @displacement of magnet and temperature -40 -150 degC Startup Time ±0.7 INLDIS+TEMP ±1.2 Deg tstartup 10 ms Table 5 System specification Global Timing Conditions Parameter Symbol Internal Master Clock Min ca 2.5 FOSC Typ Max 4.5 4.95 1/FOSC Unit MHz Note ±10% Hz Table 6 Global timing conditions Te ch ni TOSC 4.05 Revision 1.3 www.austriamicrosystems.com Page 8 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 3 Functional Description al id The AS5048 is a magnetic Hall sensor system manufactured in a CMOS process. A lateral Hall sensor array is used to measure the magnetic field components perpendicular to the surface of the chip. The AS5048 is uses self-calibration methods to eliminate signal offset and sensitivity drifts. The integrated Hall sensors are placed around the center of the device and deliver a voltage representation of the magnetic flux Bz. lv Through Sigma-Delta Analog-to-Digital Converter (ADC) and Digital Signal-Processing (DSP) algorithms, the AS5048 provides accurate high-resolution absolute angular position information. This is accomplished by a Coordinate Rotation Digital Computer (CORDIC) calculates the angle and the magnitude of the Hall array signals. am lc s on A te G nt st il The DSP is also used to provide digital information at the outputs that indicate movements of the magnet towards or away from the device’s surface, in the z-axis. A small diametrically magnetized (two-pole) standard magnet provides the angular position information. Depending on the system requirements different magnet diameters are possible. Additional flexibility is given by the wide range of the magnetic input range. The AS5048 can be combined with NeFeB, SmCo and alternative magnet materials e.g. hard ferrites. The AS5048 provides a 14-bit binary code representing the angular position of the magnet. The type of output is pre-programmed as SPI version A or I2C version B. Simultaneously a PWM output signal is available in 12 bit format. A simple programming of the zero position is possible over the interface. No additional programmer is needed. The AS5048 uses one time programmable (OTP) fuses for permanent programming of the user settings. The verification is possible over a simple digital readout of the OTP content. 4 4.1 Operation Supply Voltage Configuration The AS5048 operates at 5V ±10%, using an internal Low-Dropout (LDO) voltage regulator. In addition a 3.3V operation is possible. The VDD3V output is intended for internal use only. It must not be loaded with an external load. 3.3V Operation ca 5V Operation 10µF VDD3V VDD3V 100nF 10µF 100nF LDO ni LDO Te ch VDD5V VDD5V Internal VDD3.3V Internal VDD3.3V 4.5 - 5.5V 3.0 - 3.6V GND GND Figure 2: Connections for 5V and 3.3V supply voltages Note: The pin VDD3V must always be buffered by a 10 µF capacitor in 5V operation. It must not be left floating, as this may cause unstable internal supply voltages which may lead to larger output jitter of the measured angle. In 3V operation the VDD3V must be shorted to VDD5V. The ambient temperature Tamb is limited to 125 degC in this mode. Revision 1.3 www.austriamicrosystems.com Page 9 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor SPI Interface al id 4.2 4.2.1 SPI Interface Signals (4-Wire Mode, Wire_mode = 1) lv The 16 bit SPI Interface enables read / write access to the register blocks and is compatible to a standard micro controller interface. The SPI is active as soon as CSn is pulled low. The AS5048A then reads the digital value on the MOSI(master out slave in) input with every falling edge of CLK and writes on its MISO (master in slave out) output with the rising edge. After 16 clock cycles CSn has to be set back to a high status in order to reset some parts of the interface core. am lc s on A te G nt st il The AS5048A only supports slave operation mode. Therefore CLK for the communication as well as the CSn signal has to be provided by the test equipment. The following picture shows a basic interconnection diagram with one master and an AS5048A device and a principle schematic of the interface core. Figure 3 SPI Connection AS5048A with uC Te ch ni ca Because the interface has to decode the sent command before it can react and provide data the response of the chip to a specific command applied at a time T can be accessed in the next transmission cycle ending at T + TCOM. The data are sent and read with MSB first. Every time the chip is accessed it is sending and receiving data. Revision 1.3 Figure 4 SPI Command/Response Data Flow www.austriamicrosystems.com Page 10 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 4.2.2 SPI Timing CSn (Input ) tL tclk tclkL tclkH tH CLK (Input ) tOZ MISO (Output ) data [15] lv tMISO al id tCSn data [14] data[0] am lc s on A te G nt st il tOZ tMOSI MOSI (Input ) data[15] data [14] data [0] Figure 5 SPI Timing Diagram Parameter tL tL Description Min Max Unit Time between CSn falling edge and CLK rising edge 10 (2) ns Time between CSn falling edge and CLK rising edge 350 (1) ns TCLK Serial clock period 100 ns tCLKL Low period of serial clock 50 ns tCLKH High period of serial clock tH Time between last falling edge of CLK and rising edge of CSn 50 ns tCLK / 2 ns TCSnH High time of CSn between two transmissions 10 (2) ns TCSnH High time of CSn between two transmissions 350 (1) ns tMOSI Data input valid to clock edge tMISO CLK edge to data output valid 20 20 ca Table 7 SPI Timing Characteristics Notes: (1) Synchronization with the internal clock 2 * t CL K_ SYS + 10 ns (e.g. at 8 MHz 253 ns) Te ch ni (2) No synchronization needed because the internal clock is inactive Revision 1.3 www.austriamicrosystems.com Page 11 of 29 ns ns AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 4.2.3 SPI Connection to the Host UC am lc s on A te G nt st il lv al id Single Slave Mode Figure 6 Single Slave Mode 3 Wire Mode (read only): Te ch ni ca Multiple Slave, n+3 Wire (Separate ChipSelect) Revision 1.3 Figure 7 Multiple Slave, n+3 Wire (Separate ChipSelect) www.austriamicrosystems.com Page 12 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor am lc s on A te G nt st il lv al id Daisy Chain, 4 Wire Figure 8 Daisy Chain, 4 Wire 4.2.4 SPI Communication Command Package Every command sent to the AS5048A is represented with the following layout. Command Package MSB 14 PAR RWn 13 12 11 10 9 8 7 6 5 4 3 2 1 Address<13:0> ca Bit Bit Definition & Description PAR Parity bit (EVEN) 14 bit address code Table 8 SPI Command Package Te ch Address Indicates read(1) or write(0) command ni RWn Revision 1.3 www.austriamicrosystems.com Page 13 of 29 LSB AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 4.2.5 Read Package (Value Read from AS5048A) Read Package Bit MSB 14 PAR EF 13 12 11 10 9 8 7 6 5 4 3 Data<13:0> Parity bit (EVEN) EF Error flag indicating a transmission error in a previous host transmission Data 14 bit addressed data am lc s on A te G nt st il PAR 2 1 LSB lv Bit Definition & Description al id The read frame always contains two alarm bits, the parity and error flags and the addressed data of the previous read command. Table 9 SPI read package 4.2.6 Write Data Package (Value Written to AS5048A) The write frame is compatible to the read frame and contains two additional bits, parity flag and R flag. If the previous command was a write command a second package has to be transmitted. Data Package Bit MSB 14 PAR R 13 12 11 10 9 8 7 6 5 4 3 2 1 Data <13:0> Bit Definition & Description PAR Parity bit (EVEN) R Has to be 0 Data 14 bit data to write to former selected address Te ch ni ca Table 10 SPI write data package Revision 1.3 www.austriamicrosystems.com Page 14 of 29 LSB AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor SPI NOP x0001 Clear Error Flag x0003 Programming Control OTP Register x0016 Zero Position Hi OTP Register Zero Position Low 6 LSBs R R R/W R/W + Program R/W + Program R ni Diagnostics + x3FFD Automatic Gain Control (AGC) x3FFE Magnitude R x3FFF Angle R Te Revision 1.3 Access Type Bit Nr. Symbol 13 : 0 13 : 3 2 1 0 13 : 7 6 5 4 3 2 1 0 Default NOP 0 not used n.a. Parity Error Command Invalid Framing Error 0 Description No operation dummy information Error Register. All errors are cleared by access 13 : 8 7 : 0 13 : 6 5 : 0 13 12 11 10 9 8 7 : 0 13 : 0 13 : 0 not used Verify not used 0 Burn Programming control register. Programming must be enabled before burning the fuse(s). After programming is a verification mandatory. See programming procedure. reserved Programming Enable not used 0 Zero Position <13> : Zero Position <6> 0 : 0 not used 0 Zero Position <5> : Zero Position <0> 0 : 0 not used n.a. Comp High Comp Low COF OCF AGC value<7> : AGC value<0> Magnitude<13> : Magnitude<0> Angle <13> : Angle<0> 0 0 0 1 1 : 0 0 : 0 0 : 0 Zero Position value high byte ca x0017 ch Readout Registers Programmable Customer settings Control and Error Registers x0000 Name lv Address hex al id Register Map SPI am lc s on A te G nt st il 4.2.7 Zero Position remaining 6 lower LSB's Diagnostics flags Automatic Gain Control value. 0 decimal represents high magnetic field 255 decimal represents low magnetic field Magnitude information after ATAN calculation Angle information after ATAN calculation and zero position adder Table 11 SPI register map www.austriamicrosystems.com Page 15 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 4.2.8 SPI Interface Commands al id READ Command am lc s on A te G nt st il lv For a single READ command two transmission sequences are necessary. The first package written to the AS5048 contains the READ command (MSB-1 high) and the address the chip has to access, the second package transmitted to the AS5048 device can be any command the chip has to process next. The content of the desired register is available in the MISO register of the master device at the end of the second transmission cycle. Figure 9 READ Command WRITE Command Te ch ni ca A single WRITE command takes two transmission cycles. With a NOP command after the WRITE command you can verify the sent data with three transmission cycles because the data will be send back during the following command. Revision 1.3 Figure 10 WRITE Command www.austriamicrosystems.com Page 16 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor al id CLEAR ERROR FLAG Command am lc s on A te G nt st il lv The CLEAR ERROR FLAG command is implemented as READ command. This command clears the ERROR FLAG which is contained in every READ frame. Before the ERROR FLAG is cleared the error register content comes back with the information which error type was occurred. On the next new READ register the ERROR FLAG is cleared Figure 11 CLEAR ERROR FLAG Command The package necessary to perform a CLEAR ERROR FLAG is built up as follows. MSB 14 PAR 1 13 12 11 10 9 8 7 6 5 4 3 2 1 LSB 0 0 0 0 0 0 0 0 0 0 0 0 0 1 ni Bit ca CLEAR ERROR FLAG Command Table 12 Clear Error Flag Command ch Possible conditions which force the ERROR FLAG to be set: wrong parity wrong number of clocks (no full transmission cycle or too many clocks) Te Note: If the error flag is set to high because of a communication problem the flag remains set until it will be cleared by the CLERAR ERROR FLAG command. Revision 1.3 www.austriamicrosystems.com Page 17 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor NOP Command am lc s on A te G nt st il lv al id The NOP command represents a dummy write to the AS5048. Figure 12 NOP Command The NOP command frame looks like follows. NOP Command Bit MSB 14 13 12 11 10 9 8 7 6 5 4 3 2 1 LSB 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ca Table 13 NOP Command Te ch ni The chip’s response on this command is 0x0000 – if no error happens. Revision 1.3 www.austriamicrosystems.com Page 18 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 4.3 I²C interface al id The AS5048B supports 2-wire high-speed I²C protocol in device mode. The host MCU (master) has to initiate the data transfers. The 7-bit device address of the slave depends on the state of the OTP I2C register 21 (0x15) bit 0…4 + 2 I2C address selection pin 3 and 4. Random/Sequential Read Byte/Page Write Standard : 0 to 100kHz clock frequency (slave mode) Fast Mode : 0 to 400kHz clock frequency (slave mode) High Speed: 0 to 3.4MHz clock frequency (slave mode) am lc s on A te G nt st il lv Supported modes: The SDA signal is bidirectional and is used to read and write the serial data. The SCL signal is the clock generated by the host MCU, to synchronize the SDA data in read and write mode. The maximum I²C clock frequency is 3.4MHz, data are triggered on the rising edge of SCL. 4.3.1 I²C Electrical Specification HS-mode CB=100pF FS-mode+ Symbol Parameter Condition HS-mode CB=400pF Min Max Min Max Min Max Unit VIL LOW-Level Input Voltage -0.5 0.3VDD -0.5 0.3VDD -0.5 0.3VDD V VIH HIGH-Level Input Voltage 0.7VDD VDD + 0.5 (1) 0.7VDD VDD + 0.7VDD VDD + 0.5 (1) V 0.5 (1) Hysteresis of Schmitt Trigger Inputs VDD< 2V 0.1VDD -- 0.1VDD -- 0.1VDD -- V VOL LOW-Level Output Voltage (open-drain or open-collector) at 3mA Sink Current VDD < 2V -- 0.2VDD -- 0.2VDD -- 0.2VDD V IOL LOW-Level Output Current -- -- -- -- mA ICS Pull-up current of SCLH current source tSP Pulse Width of Spikes that must be suppressed by the Input Filter ca Vhys 20 ch ni VOL = 0.4V Input Current at each I/O Pin CB Total Capacitive Load for each Bus Line Te Ii CI/O I/O Capacitance (SDA, SCL) Input Voltage between -- -- 3 12 3 12 mA -- 50 (2) -- 10 -- 10 ns -10 +10 (3) -- 10 -- 10 µA -- 550 -- 100 -- 400 pF -- 10 -- 10 -- 10 pF Table 14 I²C Electical Specification (1) Maximum V IH = V DDmax +0.5V or 5.5V (2) Input filters on the SDA and SCL inputs suppress noise spikes of less than 50 ns. (3) I/O pins of Fast-mode and Fast-mode Plus devices must not obstruct the SDA and SCL lines if VDD is switched off. Revision 1.3 www.austriamicrosystems.com/AS5048 Page 19 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor I²C Timing FS-mode+ Symbol Parameter Condition HS-mode CB=100pF HS-mode CB=400pF (5) al id 4.3.2 Min Max Min Max Min Max Unit -- 1000 -- 3400 -- 1700 kHz 500 -- ns SCL clock Frequency tBUF Bus Free Time; time between STOP and START Condition 500 -- 500 -- tHD;STA Hold Time; (Repeated) START Condition (1) 260 -- 160 -- tLOW LOW Period of SCL Clock 500 -- 160 -- tHIGH HIGH Period of SCL Clock 260 -- 60 tSU;STA Setup Time for a Repeated START condition 260 -- tHD;DAT Data Hold Time (2) 0 tSU;DAT Data Setup Time (3) tR Rise Time of SDA and SCL Signals 50 20+0.1 Cb tF Fall time of SDA and SCL signals trCL Rise time of SCLH signal trCL1 160 ns 320 -- ns -- 120 -- ns 160 -- 160 -- ns 450 0 70 0 150 ns -- 10 -- 10 -- ns 120 -- -- -- -- ns 20+0.1 Cb 120 (4) -- -- -- -- ns Ext. pull-up source of 3mA -- -- 10 40 20 80 ns Rise time of SCLH signal after repeated START condition and after an acknowledge bit Ext. pull-up source of 3mA -- -- 10 80 20 160 ns tfCL Output rise time of SCLH signal Ext. pull-up source of 3mA -- -- 10 40 20 80 ns trDA Output rise time of SDAH signal -- -- 10 80 20 160 ns tfDA Output rise time of SDAH signal -- -- 10 80 20 160 ns tSU;STO 260 -- 160 -- 160 -- ns Noise margin at LOW level 0.1VDDp -- 0.1VDDp -- 0.1VDDp -- V Noise margin at HIGH level 0.2VDDp -- 0.2VDDp -- 0.2VDDp -- V ca am lc s on A te G nt st il -- ni lv fSCLK Setup Time for STOP Condition VnL ch VnH after this time the first clock is generated A device must internally provide a minimum hold time (120ns / max 250ns for Fast-mode Plus, 80ns / max 150ns for Highspeed mode) for the SDA signal (referred to the V I Hm in of the SCL) to bridge the undefined region of the falling edge of SCL. A fast-mode device can be used in standard-mode system, but the requirement t SU; D AT = 250ns must then e met. This is automatically the case if the device does not stretch the LOW period of the SCL signal. If such a device does strech the LOW period of the SCL signal, it must output the next data bit to the SDA line t Rm ax + T SU; DAT = 1000 + 250 = 1250ns before the SCL line is released. In Fast-mode Plus, fall time is specified the same for both output stage and bus timing. If series resistors are used this has to be considered for bus timing For capacitive bus loads between 100pF and 400pF, the timing parameters must be linearly interpolated Te (1) (2) Table 15 I²C Timing (3) (4) (5) Revision 1.3 www.austriamicrosystems.com/AS5048 Page 20 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 4.3.3 Register Table Programmable Customer settings 21 R/W I²C slave address R/W + Program 22 OTP Register Zero Position Hi R/W + Program 23 OTP Register Zero Position Low 6 LSBs R/W + Program 250 Automatic Gain Control R 252 Diagnostics R R Magnitude R ni 253 R ch 254 Angle Te 255 Revision 1.3 Symbol 7 6 5 4 3 2 1 0 7 : 5 Default Description not used Verify not used Burn 0 reserved Programming Enable not used n.a. 4 I²C address<4> : 0 7 : 0 7 6 5 : 0 7 : 0 7 : 4 3 2 1 0 7 : 0 7 6 5 : 0 7 : 0 7 6 5 : 0 : I²C address<0> Zero Position <13> : Zero Position <6> internally inverted : 0 0 : 0 ca 251 Readout Registers Programming Control Access Type Bit Nr. Programming control register. Programming must be enabled before burning the fuse(s). After programming is an verification mandatory. See programming procedure. lv 3 Name am lc s on A te G nt st il Control OTP Address dec al id The following registers / functions are accessible over the serial I²C interface. R not used n.a. Zero Position <5> : Zero Position <0> AGC value<7> : AGC value<0> 0 : 0 1 : 0 not used n.a. Comp High Comp Low COF OCF Magnitude<13> : Magnitude<6> 0 0 0 1 0 : 0 not used Magnitude<5> : Magnitude<0> Angle<13> : Angle<6> n.a. 0 : 0 0 : 0 not used n.a. Angle<5> : Angle<0> 0 : 0 Table 16 Register Map I2C www.austriamicrosystems.com/AS5048 Page 21 of 29 I²C slave address slave address consist of 5 programable bits (MSBs) and the hardware setting of Pins A1 and A2 I²C address <4> is by default not programmed and due to the inversion defined as '1' Zero Position value high byte Zero Position remaining 6 lower LSB's Automatic Gain Control value. 0 decimal represents high magnetic field 255 decimal represents low magnetic field Diagnostic flags Magnitude information afer ATAN calculation Angle Value afer ATAN calculation and zero position adder AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor X X X X X X X X ACK R/W ACK X X X X X X X X Register Address Data Byte (n) al id am lc s on A te G nt st il LSB Slave Address ACK Stop A A 1 0 0 0 0 2 1 Start Data Byte (n) HW Pins OTP cotent (Default) random write X X X X X X X X LSB Slave Address LSB Register Address R/W ACK X X X X X X X X ACK Start Start Slave Address A A 1 0 0 0 0 2 1 lv HW Pins A A 1 0 0 0 0 2 1 Stop HW Pins OTP cotent (Default) random read ACK I²C Slave address R/W ACK 4.3.4 Figure 13 Slave address construction The slave address consists of the hardware setting on pins A1, A2 and upper MSBs programmable by the user. The MSB of the slave address (yellow) is internally inverted. This means that by default the resulting data is ‘1’. A read of the I²C slave address register 21 will return a ‘0’ at the MSB. 4.4 PWM interface The AS5048 provides a pulse width modulated output (PWM), whose duty cycle is proportional to the measured angle. The PWM frequency is internally trimmed to an accuracy of ± 10% over full temperature range. This tolerance can be cancelled by measuring the complete duty cycle. The PWM signal consists of different sections: • -> PWM = ‘not(system_error)’ Data: 4095 clocks -> PWM = ‘angle_zero’ / ‘low’ (in case of error) Exit: 8 clocks ch • Error_n: 4 clocks -> PWM = ‘high’ ca • Init: 12 clocks ni • -> PWM = ‘low’ Te In case of an error the data section is set to zero. Revision 1.3 www.austriamicrosystems.com/AS5048 Page 22 of 29 AS5048A/AS5048B Datasheet Figure 14 PWM Format Symbol Value Unit T_PWM 4119 T_PWM_BIT PWM – Bit Time T_PWM_BIT 1 T_OSC PWM Resolution N_PWM 4096 bit am lc s on A te G nt st il Parameter PWM – Period Table 17 PWM Period and resolution 5 lv al id Magnetic Rotary Encoder 14-bit Angular Position Sensor Package Drawings and Markings ch ni ca Package type: TSSOP14 Figure 15 Package Marking Te 5.1.1 Assembly Lot Code The assembly lot code for standard “ YYWWIZZ ” is composed as follows: X - Interface type: A=SPI / B=I 2 C YY - Year WW - Week I - Plant identification letter ZZ - Letters for free traceability Revision 1.3 www.austriamicrosystems.com/AS5048 Page 23 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor Te ch ni ca am lc s on A te G nt st il lv al id 14-Lead Thin Shrink Small Outline Package TSSOP-14 Revision 1.3 www.austriamicrosystems.com/AS5048 Page 24 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor Application Information 6.1 Programming of the AS5048 6.1.1 Programming of the zero position al id 6 lv The absolute angle position can be permanent programmed over the interface. This could be useful for random placement of the magnet on the rotation axis. A readout at the mechanical zero position can be performed and written back into the IC. With permanent programming the position is non-reversible stored in the IC. This programming can be performed only once. 6.1.2 am lc s on A te G nt st il To simplify the calculation of the zero position it is only needed to write the value in the IC which was read out before from the angle register. Programming sequence with verification To program the zero position is needed to perform following sequence: 1. 2. 3. 4. 5. 6. 7. 8. Read angle information Set the Programming Enable bit in the OTP control register Write previous read angle position into OTP zero position register Read back for verification the zero position register data Set the Burn bit to start the automatic programming procedure Read angle information (equals to 0) Set the Verify bit to load the OTP data again into the internal registers with modified threshold comparator levels Read angle information (equals to 0) The programming can either be performed in 5V operation using the internal LDO, or in 3V operation but using a minimum supply voltage of 3.3V. In case of 3V operation, also a 10uF capacitor is required on the VDD3 pin. 6.2 Diagnostic functions of the AS5048 The AS5048 provides diagnostics functions of the IC and also diagnostic functions of the magnetic input field ca Following diagnostic flags are available: See Table 11 register address x3FFD (AS5048A) or Table 16 register address 251 dec (AS5048B) ni OCF ( O ffset C ompensation F inished), logic high indicates the finished Offset Compensation Algorithm. After power up the flag remains always to logic high. ch COF ( C ordic O ver f low), logic high indicates an out of range error in the CORDIC part. When this bit is set, the angle and magnitude data is invalid. The absolute output maintains the last valid angular value. Te COMP low , indicates a weak magnetic field. It is recommended to monitor in addition the magnitude value. COMP high , indicated a high magnetic field. It is recommended to monitor the magnitude value. Revision 1.3 www.austriamicrosystems.com/AS5048 Page 25 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 6.3 Choosing the Proper Magnet al id The AS5048 works with a variety of different magnets in size and shape. A typical magnet could be 6-8 mm in diameter and ≥2.5mm in height The magnetic field strength perpendicular to the die surface has to be in the range of ±30mT…±70mT (peak). am lc s on A te G nt st il ty p. 6-8mm diameter lv The magnet’s field strength should be verified using a gauss-meter. The magnetic flux B Z at a given distance, along a concentric circle with a radius of 1.1mm (R1), should be in the range of ±30mT…±70mT. N S Magnet axis R1 Magnet axis Vertical field component N S R1 concentric circle; radius 1.1mm Vertical field component (30…70mT) 0 Figure 16: Typical magnet and magnetic flux distribution Te Revision 1.3 360 3 60 ch ni ca Bv www.austriamicrosystems.com/AS5048 Page 26 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 6.4 Physical Placement of the Magnet 3.2 mm 1 2.5 mm Defined center am lc s on A te G nt st il Rd lv 3.2 mm al id 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: 2.5 mm Area of recommended maximum magnet misalignment Figure 17: Defined chip center and magnet displacement radius 6.5 Magnet Placement The magnet’s center axis should be aligned within a displacement radius R d of 0.25 mm (larger magnets allow more displacement e.g. 0.5 mm) from the defined center of the IC. The magnet may be placed below or above the device. The distance should be chosen such that the magnetic field on the die surface is within the specified limits The typical distance “z” between the magnet and the package surface is 0.5mm to 2.5mm, provided the use of the recommended magnet material and dimensions (6mm x 3mm). Larger distances are possible, as long as the required magnetic field strength stays within the defined limits. N Package surface 0.2299±0.100 0.2341±0.100 Te S Die surface 0.7701±0.150 ch ni ca However, a magnetic field outside the specified range may still produce usable results, but the out-of-range condition will be indicated by indication flags. Figure 18: Vertical placement of the magnet Revision 1.3 www.austriamicrosystems.com/AS5048 Page 27 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor al id Ordering Information Package 14 –Bit Programmable Magnetic Rotary Encoder with SPI-Interface Tape&Reel TSSOP 14 14 –Bit Programmable Magnetic Rotary Encoder with I2C-Interface Tape&Reel Description AS5048A-HTSP AS5048B-HTSP lv Delivery Form Model TSSOP 14 am lc s on A te G nt st il 7 Table 18: Ordering Information 8 Revision History Revision Date Owner mub Description 1.0 10-April-2012 Initial revision 1.1 16-April-2012 mub Minor correction text 1.2 09-May-2012 mub Default pin configuration added. Minor text corrections 1.3 20-June-2012 mub I2C Slave address explanation. Minor corrections. Te ch ni ca www.austriamicrosystems.com Revision 1.3 www.austriamicrosystems.com/AS5048 Page 28 of 29 AS5048A/AS5048B Datasheet Magnetic Rotary Encoder 14-bit Angular Position Sensor 9 Copyrights Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. al id Copyright © 1997-2012, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe. All products and companies mentioned are trademarks or registered trademarks of their respective companies. lv This product is protected by U.S. Patent No. 7,095,228. 10 Disclaimer am lc s on A te G nt st il Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or lifesustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for each application. Te ch ni ca The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However, austriamicrosystems AG shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of austriamicrosystems AG rendering of technical or other services. Revision 1.3 www.austriamicrosystems.com/AS5048 Page 29 of 29