AS5046ASSU

A S5046 PROGRAMMABLE 12-bit 360° MAGNETIC ANGLE ENCODER WITH ABSOLUTE 2-WIRE SERIAL AND ANALOG INTERFACES P RELIMINARY DATA SHEET 1 G eneral Description 2 • • • • K ey Features 360° contactless high resolution angular position encoding User programmable zero position 12-bit 2-wire serial interface Versatile analog output programmable angular range up to 360° programmable ratiometric output voltage range High resolution magnet distance indication 256 steps within recommended range (~0.5 to 1.8mm) 256 steps over extended range (~0 to 5mm) Mode input for optimizing noise vs. speed Alignment mode for magnet placement guidance Wide temperature range: - 40°C to + 125°C Small package: SSOP 16 (5.3mm x 6.2mm) T he AS5046 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 AS5046 provides a digital serial 12-bit as well as a programmable 10-bit ratiometric analog output that is directly proportional to the angle of a magnet, rotating over the chip. In addition, the serial interface enables a user configurable arrangement of the Hall array and allows access to each individual Sensor of the Hall Array. The AS5046 also provides high resolution information of the magnetic field strength, respectively the vertical distance of the magnet, thus adding excellent state-ofhealth information of the overall system. An internal voltage regulator allows operation of the AS5046 from 3.3V or 5.0V supplies. • • • • • 3 A pplications T he AS5046 is ideal for applications that require high resolution, a minimum of wires between controller and sensor and where the vertical distance of the magnet is of importance: • • • • R emote sensors R otate-and-push manual input devices J oysticks A pplications with extended safety requirements regarding magnet distance MagRNGn F igure 1: Typical arrangement of AS5046 and magnet Hall Array & Frontend Amplifier Hall Sensor switch matrix 14-bit ADC 14-bit ADC Sin Ang Mag 12 8 Mode CSn B enefits • • • • • • C omplete system-on-chip H igh reliability due to non-contact sensing B i-directional 2-wire interface P rogrammable ratiometric analog output I deal for application s in harsh environments R obust system, tolerant to magnet misalignment, airgap variations, temperature variations and external magnetic fields N o calibration required DSP Cos AGC 12 12 8 Absolute Interface (I²C) 8 SDA SCL 12 OTP Register Range preselect 10 DACref FB Vout AS5046 Programming Parameters 10bit DAC + DACout Prog_DI • F igure 2: AS5046 block diagram R evision 1.1 www.austriamicrosystems.com P age 1 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 4 P in Configuration 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 MagRngn Mode CSn SCL NC SDA VSS Prog VDD5V VDD3V3 NC NC Vout FB DACout DACref DO_OD DI_PD DI_PU AI DI digital output open drain digital input pull-down digital input pull-up analog input digital input S supply pin DO_T digital output /tri-state ST schmitt-trigger input AO analog output 4 .1 P in Description P ins 7, 15 a nd 1 6 a re supply pins, pins 5 , 13 a nd 1 4 a re for internal use and must be left open. P in 1 i s the magnetic field strength indicator, M agRNGn . 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. P in 2 M ODE a llows switching between filtered (slow) and unfiltered (fast mode). See section 10. P in 3 C hip Select ( CSn ; active low) selects a device for serial data transmission over the 2-wire interface. A “logic high” at CSn forces output SDA to digital tri-state. P in 4 S CL ( Serial Clock) is the clock input for data transmission over the 2-wire serial interface P in 6 S DA ( Serial Data Line) is the serial data input / output line during data transmission over the 2-wire interface P in 8 P ROG i s used to program the different operation modes, as well as the zero-position in the OTP register. P in 9 D ACref i s the external voltage reference input for the Digital-to-Analog Converter (DAC). If selected, the analog output voltage on pin 12 (V out ) will be ratiometric to the voltage on this pin. P in10 D ACout i s the unbuffered output of the DAC. This pin may be used to connect an external OPAMP, etc. to the DAC. P in 11 F B ( F eed b ack) is the inverting input of the OPAMP buffer stage. Access to this pin allows various OPAMP configurations. P in 12 V out i s 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. F igure 3: AS5046 pin configuration SSOP16 P ackage = 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 (~50kΩ). Must be connected to VSS for serial data transmission. Serial Clock Line.Clock input for 2-wire serial data transmission must be left unconnected Serial Data Line. Bi-directional I/O for 2wire serial data transmission Negative Supply Voltage (GND) OTP Programming Input. Internal pull-down resistor (~74kΩ). Should be connected to VSS if programming is not used DAC Reference voltage input for external reference DAC output (unbuffered, Ri ~8kΩ) F eed b ack, OPAMP inverting input O PAMP o ut put 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 DIO S DI_PD 3 CSn 4 5 6 7 8 SCL NC SDA VSS Prog 9 10 11 12 13 14 15 16 DACref DACout FB Vout NC NC VDD3V3 VDD5V AI AO AI AO S S T able 1: Pin description SSOP16 Revision 1.1 www.austriamicrosystems.com P age 2 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 5 5 .1 E lectrical Characteristics A bsolute Maximum Ratings (non operating) S tresses beyond those listed under “Absolute Maximum Ratings“ may cause permanent damage to the device. These are stress ratings only. Functional operation of the device at these or any other conditions beyond those indicated under “Operating Conditions” is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Parameter DC supply voltage Symbol VDD5V VDD3V3 -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 -55 -100 Min -0.3 Max 7 5 VDD5V +0.3 5 7.5 100 ±2 125 260 85 mA kV °C °C % V Unit V V Note Pin VDD5V Pin VDD3V3 Pins MagRngn, Mode, CSn, CLK, DO, DACout, FB, Vout Pin DACref Pin PROG_DI Norm: JEDEC 78 Norm: MIL 883 E method 3015 Min – 67°F ; Max +257°F t=20 to 40s, Norm: IPC/JEDEC J-Std-020C Lead finish 100% Sn “matte tin” 5 .2 O perating Conditions Symbol Tamb Isupp VDD5V VDD3V3 VDD5V VDD3V3 4.5 3.0 3.0 3.0 Min -40 16 5.0 3.3 3.3 3.3 Typ Max 125 21 5.5 3.6 3.6 3.6 Unit °C mA V V V V 5V operation 3.3V operation (pin VDD5V and VDD3V3 connected) Note -40°F…+257°F Parameter Ambient temperature Supply current Supply voltage at pin VDD5V Voltage regulator output voltage at pin VDD3V3 Supply voltage at pin VDD5V Supply voltage at pin VDD3V3 Revision 1.1 www.austriamicrosystems.com P age 3 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 5 .3 5 .3.1 D C Characteristics for Digital Inputs and Outputs C MOS Schmitt-Trigger Inputs: SCL, CSn (internal Pull-up), Mode (internal Pull-down) Symbol VIH VIL VIon- VIoff ILEAK IiL IiH 1 -1 -30 30 1 -100 100 µA Min 0.7 * VDD5V 0.3 * VDD5V Max Unit V V V Pin CLK, VDD5V = 5.0V Pin CSn, VDD5V= 5.0V Pin Mode, VDD5V= 5.0V Note Normal operation (operating conditions: Tamb = -40 to +125°C, 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 5 .3.2 C MOS Input: Program Input (Prog) ( operating conditions: T amb = - 40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted) Parameter High level input voltage High level input voltage Low level input voltage Pull-down high level input current Symbol VIH VPROG VIL IiL Min 0.7 * VDD5V Max 5 Unit V V V µA VDD5V: 5.5V During programming Note See “programming conditions” 0.3 * VDD5V 100 5 .3.3 C MOS Output Open Drain: MagRngn ( operating conditions: T amb = - 40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted) Parameter Low level output voltage Output current Open drain leakage current Symbol VOL IO IOZ Min Max VSS+0.4 4 2 1 Unit V mA µA VDD5V: 4.5V VDD5V: 3V Note 5 .3.4 T ristate CMOS Output: SDA Symbol VOH VOL IO Min VDD5V –0.5 VSS+0.4 4 2 Max Unit V V mA mA µA VDD5V: 4.5V VDD5V: 3V Note (operating conditions: Tamb = -40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted) Parameter High level output voltage Low level output voltage Output current Tri-state leakage current IOZ 1 Revision 1.1 www.austriamicrosystems.com P age 4 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 5 .3.5 Resolution D igital-to-Analog Converter Symbol Min Typ 10 VOUTM1 VOUTM2 0 0.10 *Vref Vref 0.90 *Vref 8 0.2 VDD3V3 - 0.2 VDD5V / 2 Max Unit bit V V kΩ V V LSB LSB LSB LSB 0……100% Vref (default) 10…..90% Vref Unbuffered Pin DACout (#10) DAC reference = external: Pin: DACref (#9) DAC reference = internal Non-Linearity of DAC and OPAMP; -40….+125°C, For all analog modes: 1LSB = Vref / 1024 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 Note OTP setting Parameter Output Range Output resistance DAC reference voltage (DAC full scale range) Integral Non-Linearity Differential Non-Linearity ROut,DAC Vref INLDAC DNLDAC +/- 1.5 +/- 0.5 1 Analog output hysteresis Hyst 2 5 .3.6 O PAMP Output Stage Symbol V DD5V CL RL A0 VosOP VoutL VoutH Isink Isource V noi se 0.95 * VDD5V 4.8 4.6 1 60 220 2 Gain 50 66 490 4.7 92 -5 130 144 5 Min 3.0 Typ Max 5.5 100 Unit V pF kΩ dB mV 3 sigma Linear range of analog output Permanent short V out t o VDD5V Permanent short V out t o VSS circuit circuit current: current: 3 .3V operation Note Parameter Power Supply Range P arallel Load Capacitance P arallel Load Resistance O pen Loop Gain Offset Voltage RTI O utput Range Low O utput Range High current capability sink current capability source Output noise 0.05 * VDD5V V V mA mA µVrms Over full temperature range; BW= 1Hz…10MHz,Gain = 2x I nternal; OTP: FB_int EN = 1 External OTP: FB_int EN = 0 (default) With external resistors, pins Vout [#12] and FB [#11]: see F igure 17 OPAMP gain (non-inverting) 1 4 Revision 1.1 www.austriamicrosystems.com P age 5 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 5 .4 M agnetic Input Specification ( operating conditions: T amb = - 40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted) Two-pole cylindrical diametrically magnetised source: Parameter Diameter Thickness Magnetic input field amplitude Magnetic offset Field non-linearity fmag_abs Symbol dmag tmag Bpk Boff Min 4 2.5 45 75 ± 10 5 10 Typ 6 Max Unit mm mm mT mT % Hz Note Recommended magnet: Ø 6mm x 2.5mm 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_inc Disp -0.12 -0.035 166 0.25 Hz mm %/K Displacement radius Recommended magnet material and temperature drift 5 .5 E lectrical System Specifications ( operating conditions: T amb = - 40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted) Parameter Resolution 1) Integral non-linearity (optimum) 1) Symbol RES INLopt Min Typ Max 12 ± 0.5 Unit bit deg Note 0.088 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 +125°C Best line fit = (Errmax – Errmin) / 2 Integral non-linearity 1) INL ± 1.4 deg Over displacement tolerance with 6mm diameter magnet, Tamb = -40 to +125°C 12bit, 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) ms 80 96 tdelay 384 µs slow mode (pin MODE=0 or open) fast mode (pin MODE=1) slow mode (pin MODE=0 or open) Integral non-linearity (optimum) 1) INLtemp ± 0.9 deg Differential non-linearity 1) Transition noise 1) 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 DNL TN ± 0.044 0.06 0.03 deg Deg RMS Von Voff 1.37 1.08 2.2 1.9 2.9 2.6 20 V V tPwrUp Revision 1.1 www.austriamicrosystems.com P age 6 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet Parameter Internal sampling rate for absolute output Internal sampling rate for absolute output Read-out frequency Symbol fS,mode0 Min 2.48 2.35 9.90 9.38 >0 Typ 2.61 2.61 10.42 10.42 Max 2.74 2.87 10.94 11.46 1 Unit kHz Note Tamb = 25°C, slow mode (pin MODE=0 or open) Tamb = -40 to +125°C, slow mode (pin MODE=0 or open) Tamb = 25°C, fast mode (pin MODE = 1) Tamb = -40 to +125°C, : fast mode (pin MODE = 1) Max. clock frequency to read out serial data fS,mode1 CLK kHz MHz N ote: 1) digital interface 4095 α 12bit code Actual curve 2 1 0 4095 TN DNL+1LSB INL 0.09° Ideal curve 2048 2048 0 0° 180° F igure 4: Integral and differential non-linearity (exaggerated curve) 360 ° α [degrees] I ntegral 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. 5 .6 T iming Characteristics 2 -wire Serial Interface (operating conditions: T amb = - 40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted) Parameter Data output activated (logic high) First data shifted to output register Start of data output Data output valid Data output tristate Pulse width of CSn Read-out frequency Symbol t DO active tCLK FE T CLK / 2 t DO valid t DO tristate t CSn fCLK 500 >0 1 500 500 357 375 394 100 Min Typ Max 100 Unit ns ns ns ns ns ns MHz Note Time between falling edge of CSn and data output activated Time between falling edge of CSn and first falling edge of CLK Rising edge of CLK shifts out one bit at a time Time between rising edge of CLK and data output valid After the last bit DO changes back to “tristate” CSn = high; To initiate read-out of next angular position Clock frequency to read out serial data Revision 1.1 www.austriamicrosystems.com P age 7 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 5 .7 P rogramming Conditions ( operating conditions: T amb = - 40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless otherwise noted) P arameter 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 S ymbol t Prog enable t Data in t Data in valid t Load PROG t PrgR t PrgH CLK PROG t PROG t PROG finished V PROG V ProgOff I PROG CLKAread Vprogrammed M in 2 2 250 3 0 0 T yp M ax U nit µs µs ns µs µs N ote Time between rising edge at Prog pin and rising edge of CSn Write data at the rising edge of CLKPROG 5 250 µs kHz µs µs 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) 7.4 7.5 1 130 100 100 V V mA kHz mV Vunprogrammed 1 V 6 F unctional Description T he AS5046 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 AS5046 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). In addition, two 8-bit registers are available that allow determination of the magnetic field strength over a wide range. A small low cost diametrically magnetized (two-pole) standard magnet, centered over the chip, is used as the input device. The AS5046 senses the orientation of the magnetic field and calculates a 12-bit binary code. This code can be accessed via a bi-directional serial two-wire interface. In addition to the digital output, the absolute angle is converted into a 1024-step (10-bit) 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 10-90% *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. Revision 1.1 www.austriamicrosystems.com P age 8 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet T he AS5046 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. 7 3 .3V / 5V Operation T he AS5046 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 5 ). For 5V operation, the 5V supply is connected to pin VDD5V, while VDD3V3 (LDO output) must be buffered by a 2.2...10µF capacitor, which should be placed close to the supply pin (see Figure 5). 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 5). A buffer capacitor of 100nF is recommended in both cases close to pin VDD5V. Note that pin VDD3V3 must always be buffered by a capacitor. It must not be left floating, as this may cause an instable internal 3.3V supply voltage which may lead to larger than normal jitter of the measured angle. 5V Operation 2µ2...10µF VDD3V3 100n VDD5V LDO Internal VDD DO 4.5 - 5.5V I N T E R F A C E MODE CLK CSn VSS Prog 3.3V Operation VDD3V3 100n VDD5V LDO Internal VDD DO 3.0 - 3.6V I N T E R F A C E MODE CLK CSn VSS Prog F igure 5: Connections for 5V / 3.3V supply voltages Revision 1.1 www.austriamicrosystems.com P age 9 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 8 Two Wire Serial Interface T he AS5046 is accessible via an bi-directional serial interface. CSn must be low during serial data transmission. 8 .1 S erial Interface Timing Diagrams T he registers in the AS5046 are available in a data length of 8 bit (1 byte), 24 bit (3 bytes) and 32 bit (4 bytes). Shown below in Figure 6 is a common 8-bit data transfer. F igure 6: 8-bit serial Read / Write timing F igure 7 shows a transfer timing diagram for the first 16 bits of the Serial Interface Unit. F igure 7: 16-bit serial Read / Write timing 9 A ccessible Registers for Serial Interface S tatus Register I nternal T ype I dentifier I nternal A ddress R egister B it C ount R ead / W rite N ote 10 bit angle Serial Interface Unit 0101 000 Programmable with A2...A0 1) 6 bit status 32 Read only 8 bit magnitude 2 bit angle Hall Sensor Front End 0001 000 -111 fixed address range 000 000 fixed address Fixed address 8 24 8 Read / Write Read / Write 2) 8 selectable Hall front-end status registers 12bit SIN , 12bit COS input AGC Counter ADC outputs, SIN/COS 0100 signal bus Automatic Gain Control 0111 Read / Write 3) T able 2: Serial register overview Revision 1.1 www.austriamicrosystems.com P age 10 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet N otes: 1) 2) 3) T his address is also modified with the analog mode setting W riting a value to any of the SIN- COS- registers halts the conversion loop and calculates an angle that is given by the values in the SIN and COS registers. A Read command from these registers restarts the automatic conversion loop. W riting a value to the AGC counter register halts the automatic gain control loop and sets the AGC to the value written in this register. The angle conversion loop continues to operate. A Read command from the AGC register restarts the automatic gain control loop. 9 .1 S erial Interface Unit (Type ID: 0101) T he Serial Interface Unit contains 32 bits of data: N ote that the angle information is only valid, if the Hall Sensor Front-end is configured properly. See Table 4 for more information. 9 .1.1 1 2-bit Angle Information t he 12-bit angle data consists of two blocks: the upper 10-bits in bytes 1 & 2 and the lower two bits in byte 4 9 .1.2 6 -bit Status Information S tatus bit 1 S tatus bit 2 SIU bit 11 SIU bit 12 Offset Comp Finish CORDIC Over Flow OCF COF must be 1 for valid data must be 0; if this bit is set, the angular data is invalid LINearity warning bit. Should be 0 for normal operation. Will be 1 when the magnetic field is too high or too low This bit is set temporarily when the magnetic field increases, when the magnet is pushed towards the IC This bit is set temporarily when the magnetic field decreases, when the magnet is pulled away from the IC Even parity check bit of bytes 1 & 2 S tatus bit 3 SIU bit 13 Lin Alarm LIN S tatus bit 4 SIU bit 14 Mag Incr. M_I S tatus bit 5 S tatus bit 6 SIU bit 15 SIU bit 16 Mag Decr. Even Parity M_D P T able 3: Status bits of byte 2 of the SIU 9 .1.3 8 -bit Magnitude Information T he magnitude information is a value that is proportional to the magnetic field strength. A strong magnet (or close distance between magnet and chip) will result in a high magnitude value and vice versa. When the automatic gain control (AGC) is active (default state), it tries to keep the magnitude value stable at a value of 3F H . Revision 1.1 www.austriamicrosystems.com P age 11 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 9 .2 H all Sensor Front End (Type ID: 0001) T he Hall Sensor Front End allows configuration of each Hall Sensor. Each sensor can be disabled or connected to either the SIN or COS signal bus. Additionally, each sensor can be inverted for differential measurement. Each Hall Sensor is selected through a device address for the type identifier 0001, address 000 selects Hall Sensor H0 (see Figure 8) address 111 selects Hall Sensor H7 (see Figure 8) F igure 8: Location of Hall Elements on chip (top view) N ote: If the magnet is placed like shown in Figure 8 the encoder reading will be of zero. For each Hall Sensor, the corresponding Front End contains 8 bits Type ID: 0001 A ddr. 000…111 TestEN SenseEN NC NC Byte1 COS_EN SIN_EN INV PD T estEN: SenseEN: COS_EN: SIN_EN: INV: PD: always set to 0 set to 1 for enabled Hall Elements, set to 0 for disabled Hall Elements set to 0 for disabled Hall Elements, set to 1 if this Hall Element should be added to the COS signal bus. It is also possible to enable multiple Hall sensors to this bus set to 0 for disabled Hall Elements, set to 1 if this Hall Element should be added to the SIN signal bus. It is also possible to enable multiple Hall sensors to this bus set to 1 if the Hall Element should be inverted for differential measurement. set to 0 if the Hall Element should not be inverted set to 0 for normal operation, set to 1 if the Hall Sensor should be powered down. N ote: W hen enabling or disabling individual Hall elements to the SIN- and COS- signal buses it is recommended to allow several milliseconds (typ. 5ms) of dwelling time until the signal is stable and eventual offsets are compensated. Revision 1.1 www.austriamicrosystems.com P age 12 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 9 .3 H all Sensor Front-End Configuration T he default configuration for the Hall Sensor Front-End is set for angle measurement. This configuration must always be programmed when an angle should be measured and read from the Serial Interface Unit register. A ddr F E0 F E1 F E2 F E3 F E4 F E5 F E6 F E7 0 00 0 01 0 10 0 11 1 00 1 01 1 10 1 11 t estEN 0 0 0 0 0 0 0 0 S enseEN 1 1 1 1 1 1 1 1 NC 0 0 0 0 0 0 0 0 NC 0 0 0 0 0 0 0 0 C OS_EN 0 0 1 1 0 0 1 1 S IN_EN 1 1 0 0 1 1 0 0 I nv 0 0 0 0 1 1 1 1 PD 0 0 0 0 0 0 0 0 T able 4: Hall Sensor Front-End default configuration T he following configuration example selects Hall Sensor 0 and assigns it to the SIN signal bus: A ddr F E0 F E1 F E2 F E3 F E4 F E5 F E6 F E7 0 00 0 01 0 10 0 11 1 00 1 01 1 10 1 11 t estEN 0 0 0 0 0 0 0 0 S enseEN 1 0 0 0 0 0 0 0 NC 0 0 0 0 0 0 0 0 NC 0 0 0 0 0 0 0 0 C OS_EN 0 0 0 0 0 0 0 0 S IN_EN 1 0 0 0 0 0 0 0 I nv 0 0 0 0 0 0 0 0 PD 0 0 0 0 0 0 0 0 T able 5: Example: Readout of a single Hall Sensor (Sensor #0) T his example uses two opposite Hall sensors 1 and 5 in differential mode and assigns the resulting signal to the COS signal bus: A ddr F E0 F E1 F E2 F E3 F E4 F E5 F E6 F E7 0 00 0 01 0 10 0 11 1 00 1 01 1 10 1 11 t estEN 0 0 0 0 0 0 0 0 S enseEN 0 1 0 0 0 1 0 0 NC 0 0 0 0 0 0 0 0 NC 0 0 0 0 0 0 0 0 C OS_EN 0 1 0 0 0 1 0 0 S IN_EN 0 0 0 0 0 0 0 0 I nv 0 0 0 0 0 1 0 0 PD 0 0 0 0 0 0 0 0 T able 6: Example: Differential measurement of two opposite Hall Sensors (#1 and 5) Revision 1.1 www.austriamicrosystems.com P age 13 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 9 .4 A nalog-Digital Converter Outputs, SIN/COS Signal Bus (Type ID: 0100) Byte 1 12-bit ADC output: COS signal bus Byte 2 12-bit ADC output: SIN signal bus Upper 8 bits 6 5 4 11 10 9 8 7 6 5 4 3 Byte 3 COS signal bus Lower 4 bits 2 1 0 3 SIN signal bus Lower 4 bits 2 1 0 T ype ID: 0100 A ddr. 000 11 10 Upper 8 bits 9 8 7 T he analog signals on the SIN- and COS- buses are converted into a signed 12-bit digital value by two ADC’s, one for each bus. To read the signal from one or more Hall Sensors, first assign a signal bus (SIN, COS) for each Hall Sensor in the Hall Sensor front-end and then read the corresponding amplitude value from the ADC output register. Note that the ADC’s are 14-bit (see Block diagram, Figure 2), but only 12-bit are available to the user. The available 12-bit ADC output is again split into an upper 8-bit block (available in bytes 1 & 2) and a lower 4-bit block in byte 3. The resulting 12-bit value is formatted as a signed 12-bit value and has a range from -2048…+2047 (decimal). Bit 11 (MSB) is the sign bit; if this bit is set, the Sin/Cos value is negative. 9 .5 A utomatic Gain Control Register (Type ID: 0111) T he Automatic Gain Control is active in the “green” range of the magnetic field, when the magnetic field is within ~35…63mT. If the magnetic field is too low, e.g. when the magnet is too far away from the chip, the AGC register will be FF H , if the magnetic field is too strong, e.g. when the magnet is too close to the chip, the AGC register will be 00 H . The Automatic Gain control can be disabled by writing a value into this register. It will be enabled by reading from this register. The AGC tries to maintain a constant magnitude value of 3F H . If the AGC has reached its upper or lower limit, the magnitude value can no longer be maintained ad 3F H a nd will also change accordingly (see 9.1.3 and 9.6). Type ID: 0111 A ddr. 000 AGC7 AGC6 AGC5 AGC5 Byte 1 AGC3 AGC2 AGC1 AGC0 Revision 1.1 www.austriamicrosystems.com P age 14 of 33 A S5046 Programmable 360° Magnetic Angle Encoder – Preliminary Data Sheet 9 .6 A GC and Magnitude Registers T he AS5046 allows the readout of two additional registers related to magnetic field strength: magnitude and AGC registers. Figure 9 shows a graphic example of the interrelations of these two registers in respect to the magnetic field strength of the magnet (all register levels are in decimal format). at a low magnetic field strength (below level B1 / B2) the magnitude will be