AEAT-6600-T16 10 to16-Bit Programmable Angular Magnetic Encoder IC Data Sheet Description Features The Avago AEAT-6600 angular magnetic encoder IC is a 5 V or 3.3 V operation contact less magnetic rotary encoder for accurate angular 3-wire or 2-wire SSI interface mode for absolute output measurement over a full turn of 360 degrees. Incremental ABI or UVW, and PWM output modes It is a system-on-chip, combining integrated Hall elements, User-programmable zero position, direction & index analog front end and digital signal processing in a single pulse width device. Easy magnet alignment with magnetic field strength To measure the angle, only a simple two-pole magnet, output and alignment mode rotating over the center of the chip, is required. The Power-down mode to reduce current consumption magnet may be placed above or below the IC. TSSOP-16 IC package The absolute angle measurement provides instant indica- RoHS compliant tion of the magnets angular position with a resolution of 0.005 = 65 536 positions per revolution. This digital data Specifications is available as a serial bit stream and as a PWM signal. Absolute 10-bits to 16-bits resolution An internal voltage regulator allows the AEAT-6600 to operate at either 3.3 V or 5 V supplies. Incremental output resolutions 8 to 1024 CPR -40 C to 125 C operating temperature range Applications 3-phase commutation for brushless DC motor Resolver and potentiometer replacement Industrial automation and robotics NOTE: This product is not specifically designed or manu - factured for use in any specific device. Customers are Figure 1. AEAT-6600 Series TSSOP-16 IC Package solely responsible for determining the suitability of this product for its intended application and solely liable for all loss, damage, expense or liability in connection with such use.Definitions Functional Description The AEAT-6600 is manufactured with a CMOS standard Electrical Degree (e): Resolution x 360 electrical degrees = process and uses a Hall technology for sensing the 360 mechanical degrees. magnetic field distribution across the surface of the Cycle (C): One cycle of the incremental signal is 360 me- chip. The integrated Hall elements are placed around the chanical degrees/Resolution and is equal to 360 electrical center of the device and deliver a voltage representation degrees (e). of the magnetic field at the surface of the IC. The Digital Signal Processing (DSP) circuit converts the data from the Cycle Error (C): The difference between the actual cycle Hall sensor into absolute angular position (DO/DI pin) as width and the ideal cycle width corresponding to a shaft an absolute output or converted into digital output (A/U, angle displacement of 1/Resolution. The accumulated B/V, I/W pins) by the incremental circuit. cycle error leads to position error. The DSP circuit also provides digital information at the Pulse Width (P): The number of electrical degrees that an out- outputs MagHi and MagLo that indicate movements of put is high during one cycle, nominally 180e or a cycle. the used magnet towards or away from the devices surface. Pulse Width Error (P): The deviation in electrical degrees of A small low cost diametrically magnetized (two-pole) stan- the pulse width from its ideal value of 180e. dard magnet provides the angular position information. State Width (S): The number of electrical degrees between The AEAT-6600 senses the orientation of the magnetic a transition in the output of channel A and the neighbor- field and calculates a 10 to 16-bit binary code. This code ing transition in the output of channel B. There are 4 states can be accessed via a Synchronous Serial Interface (SSI). per cycle, each nominally 90e. In addition, an absolute angular representation is given by a Pulse Width Modulated signal at pin 8 (PWM). The State Width Error ( S): The deviation in electrical degrees of AEAT-6600 is tolerant to magnet misalignment and each state width from its ideal value of 90e. magnetic stray fields due to local measurement technique Phase ( ): The number of electrical degrees between the and Hall sensor conditioning circuitry. center of the high state on channel A and the center of the The OTP block provides an access to program to a specific high state on channel B. resolution and output modes through a PROG pin Phase Error ( ): The deviation in electrical degrees of the (pin 13). phase from its ideal value of 90e. Index Pulse Width (P ): The number of electrical degrees O NOTE: For further information regarding the operating that an index pulse is active within the cycle that coincides mode and application, please refer to the Application Note with the absolute zero position. The index pulse width is (AV02-2791EN). For programming tool and software ap- also expressed in terms of LSB (least significant bit) counts plication, please refer to the User Manual (AV02-2803EN). corresponding to the encoder resolution. Integral non-linearity (INL): The maximum deviation bet- ween actual angular position and the position indicated by the encoders output count, over one revolution. It is defined as the most positive linearity error +INL or the most negative linearity error INL from the best fit line, whichever is larger. 1024 MAG HI MAG LO PWM ATST PWM Most Negative Linearity Error -INL Absolute DO DI Absolute data Data 1 ALIGN Synchronous CLK NCS 512 Serial Interface PROG DSP Absolute A/U Data 2 Hall Incremental B/V Sensor Conversion ICFE I/W Data Most Postive Linearity Error +INL Con guration Registers Ideal Curve VPP OTP Actual Curve OTP 0 0 90 180 270 360 Angular Position (Mechanical Degree) Figure 2. Integral Non-Linearity Example Figure 3. Polaris block diagram 2 Encoder Output Count