SLLSFX9 December   2024 MCF8316D

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Characteristics of the SDA and SCL bus for Standard and Fast mode
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Output Stage
      2. 6.3.2  Device Interface
        1. 6.3.2.1 Interface - Control and Monitoring
        2. 6.3.2.2 I2C Interface
      3. 6.3.3  Step-Down Mixed-Mode Buck Regulator
        1. 6.3.3.1 Buck in Inductor Mode
        2. 6.3.3.2 Buck in Resistor mode
        3. 6.3.3.3 Buck Regulator with External LDO
        4. 6.3.3.4 AVDD Power Sequencing from Buck Regulator
        5. 6.3.3.5 Mixed Mode Buck Operation and Control
      4. 6.3.4  AVDD Linear Voltage Regulator
      5. 6.3.5  Charge Pump
      6. 6.3.6  Slew Rate Control
      7. 6.3.7  Cross Conduction (Dead Time)
      8. 6.3.8  Motor Control Input Sources
        1. 6.3.8.1 Analog-Mode Motor Control
        2. 6.3.8.2 PWM-Mode Motor Control
        3. 6.3.8.3 I2C-based Motor Control
        4. 6.3.8.4 Frequency-Mode Motor Control
        5. 6.3.8.5 Input Reference Profiles
          1. 6.3.8.5.1 Linear Control Profiles
          2. 6.3.8.5.2 Staircase Control Profiles
          3. 6.3.8.5.3 Forward-Reverse Profiles
          4. 6.3.8.5.4 Multi-Reference Mode Operation
          5. 6.3.8.5.5 Input Reference Transfer Function without Profiler
      9. 6.3.9  Starting the Motor Under Different Initial Conditions
        1. 6.3.9.1 Case 1 – Motor is Stationary
        2. 6.3.9.2 Case 2 – Motor is Spinning in the Forward Direction
        3. 6.3.9.3 Case 3 – Motor is Spinning in the Reverse Direction
      10. 6.3.10 Motor Start Sequence (MSS)
        1. 6.3.10.1 Initial Speed Detect (ISD)
        2. 6.3.10.2 Motor Resynchronization
        3. 6.3.10.3 Reverse Drive
          1. 6.3.10.3.1 Reverse Drive Tuning
        4. 6.3.10.4 Motor Start-up
          1. 6.3.10.4.1 Align
          2. 6.3.10.4.2 Double Align
          3. 6.3.10.4.3 Initial Position Detection (IPD)
            1. 6.3.10.4.3.1 IPD Operation
            2. 6.3.10.4.3.2 IPD Release Mode
            3. 6.3.10.4.3.3 IPD Advance Angle
          4. 6.3.10.4.4 Slow First Cycle Startup
          5. 6.3.10.4.5 Open Loop
          6. 6.3.10.4.6 Transition from Open to Closed Loop
      11. 6.3.11 Closed Loop Operation
        1. 6.3.11.1 Closed Loop Acceleration/Deceleration Slew Rate
        2. 6.3.11.2 Speed PI Control
        3. 6.3.11.3 Current PI Control
        4. 6.3.11.4 Power Control Mode
        5. 6.3.11.5 Current (Torque) Control Mode
        6. 6.3.11.6 Modulation Index Control
        7. 6.3.11.7 Overmodulation
        8. 6.3.11.8 Motor Speed Limit
        9. 6.3.11.9 Input DC Power Limit
      12. 6.3.12 Flux Weakening Control
      13. 6.3.13 Motor Parameters
        1. 6.3.13.1 Motor Resistance
        2. 6.3.13.2 Motor Inductance
        3. 6.3.13.3 Motor Back-EMF constant
      14. 6.3.14 Motor Parameter Extraction Tool (MPET)
      15. 6.3.15 Anti-Voltage Surge (AVS)
      16. 6.3.16 Active Braking
      17. 6.3.17 Output PWM Switching Frequency
      18. 6.3.18 PWM Dithering
      19. 6.3.19 PWM Modulation Schemes
      20. 6.3.20 Dead Time Compensation
      21. 6.3.21 Motor Stop Options
        1. 6.3.21.1 Coast (Hi-Z) Mode
        2. 6.3.21.2 Recirculation Mode
        3. 6.3.21.3 Low-Side Braking
        4. 6.3.21.4 High-Side Braking
        5. 6.3.21.5 Active Spin-Down
      22. 6.3.22 Align Braking
      23. 6.3.23 FG Configuration
        1. 6.3.23.1 FG Output Frequency
        2. 6.3.23.2 FG during Open and Closed Loop States
        3. 6.3.23.3 FG during Fault and Idle States
      24. 6.3.24 Protections
        1. 6.3.24.1  VM Supply Undervoltage Lockout
        2. 6.3.24.2  AVDD Undervoltage Lockout (AVDD_UV)
        3. 6.3.24.3  BUCK Under Voltage Lockout (BUCK_UV)
        4. 6.3.24.4  VCP Charge Pump Undervoltage Lockout (CPUV)
        5. 6.3.24.5  Overvoltage Protection (OVP)
        6. 6.3.24.6  Overcurrent Protection (OCP)
          1. 6.3.24.6.1 OCP Latched Shutdown (OCP_MODE = 00b)
          2. 6.3.24.6.2 OCP Automatic Retry (OCP_MODE = 01b)
        7. 6.3.24.7  Buck Overcurrent Protection
        8. 6.3.24.8  Hardware Lock Detection Current Limit (HW_LOCK_ILIMIT)
          1. 6.3.24.8.1 HW_LOCK_ILIMIT Latched Shutdown
          2. 6.3.24.8.2 HW_LOCK_ILIMIT Automatic Recovery
          3. 6.3.24.8.3 HW_LOCK_ILIMIT Report Only
          4. 6.3.24.8.4 HW_LOCK_ILIMIT Disabled
        9. 6.3.24.9  Lock Detection Current Limit (LOCK_ILIMIT)
          1. 6.3.24.9.1 LOCK_ILIMIT Latched Shutdown
          2. 6.3.24.9.2 LOCK_ILIMIT Automatic Recovery
          3. 6.3.24.9.3 LOCK_ILIMIT Report Only
          4. 6.3.24.9.4 LOCK_ILIMIT Disabled
        10. 6.3.24.10 Motor Lock Detection
          1. 6.3.24.10.1 Lock 1: Abnormal Speed (ABN_SPEED)
          2. 6.3.24.10.2 Lock 2: Abnormal BEMF (ABN_BEMF)
          3. 6.3.24.10.3 Lock3: No-Motor Fault (NO_MTR)
        11. 6.3.24.11 Motor Lock (MTR_LCK)
          1. 6.3.24.11.1 MTR_LCK Latched Shutdown
          2. 6.3.24.11.2 MTR_LCK Automatic Recovery
          3. 6.3.24.11.3 MTR_LCK Report Only
          4. 6.3.24.11.4 MTR_LCK Disabled
        12. 6.3.24.12 EEPROM Fault
        13. 6.3.24.13 I2C CRC Fault
        14. 6.3.24.14 Minimum VM (Undervoltage) Protection
        15. 6.3.24.15 Maximum VM (Overvoltage) Protection
        16. 6.3.24.16 MPET Faults
        17. 6.3.24.17 IPD Faults
        18. 6.3.24.18 FET Thermal Warning (OTW)
        19. 6.3.24.19 FET Thermal Shutdown (TSD_FET)
    4. 6.4 Device Functional Modes
      1. 6.4.1 Functional Modes
        1. 6.4.1.1 Sleep Mode
        2. 6.4.1.2 Standby Mode
        3. 6.4.1.3 Fault Reset (CLR_FLT)
    5. 6.5 External Interface
      1. 6.5.1 DRVOFF Functionality
      2. 6.5.2 DAC outputs
      3. 6.5.3 Current Sense Output
      4. 6.5.4 Oscillator Source
        1. 6.5.4.1 External Clock Source
      5. 6.5.5 External Watchdog
    6. 6.6 EEPROM access and I2C interface
      1. 6.6.1 EEPROM Access
        1. 6.6.1.1 EEPROM Write
        2. 6.6.1.2 EEPROM Read
        3. 6.6.1.3 EEPROM Security
      2. 6.6.2 I2C Serial Interface
        1. 6.6.2.1 I2C Data Word
        2. 6.6.2.2 I2C Write Transaction
        3. 6.6.2.3 I2C Read Transaction
        4. 6.6.2.4 I2C Communication Protocol Packet Examples
        5. 6.6.2.5 I2C Clock Stretching
        6. 6.6.2.6 CRC Byte Calculation
    7. 6.7 EEPROM (Non-Volatile) Register Map
      1. 6.7.1 Algorithm_Configuration Registers
      2. 6.7.2 Fault_Configuration Registers
      3. 6.7.3 Hardware_Configuration Registers
      4. 6.7.4 Internal_Algorithm_Configuration Registers
    8. 6.8 RAM (Volatile) Register Map
      1. 6.8.1 Fault_Status Registers
      2. 6.8.2 System_Status Registers
      3. 6.8.3 Device_Control Registers
      4. 6.8.4 Algorithm_Control Registers
      5. 6.8.5 Algorithm_Variables Registers
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Application Curves
        1. 7.2.1.1 Motor startup
        2. 7.2.1.2 MPET
        3. 7.2.1.3 Dead time compensation
        4. 7.2.1.4 Auto handoff
        5. 7.2.1.5 Anti voltage surge (AVS)
        6. 7.2.1.6 Real time variable tracking using DACOUT
  9. 8 Power Supply Recommendations
    1. 8.1 Bulk Capacitance
  10. 9 Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Layout Example
    3. 9.3 Thermal Considerations
      1. 9.3.1 Power Dissipation
  11. 10Device and Documentation Support
    1. 10.1 Support Resources
    2. 10.2 Trademarks
    3. 10.3 Electrostatic Discharge Caution
    4. 10.4 Glossary
  12. 11Mechanical, Packaging, and Orderable Information
  13. 12Revision History

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)

6.3.14 Motor Parameter Extraction Tool (MPET)

The MCF8316D uses motor winding resistance, motor winding inductance and Back-EMF constant to estimate motor position in closed loop operation. The MCF8316D has capability of automatically measuring motor parameters in offline state, rather than having the user enter the values themselves. The MPET routine measures motor winding resistance, inductance, back EMF constant and mechanical load inertia and frictional coefficients. Offline measurement of parameters takes place before normal motor operation. TI recommends to estimate the motor parameters before motor startup to minimize the impact caused due to possible parameter variations.

Figure 6-49 shows the sequence of operation in the MPET routine. The MPET routine is entered when either the MPET_CMD bit is set to 1b or a non-zero target speed is set. The MPET routine consists of four steps namely, IPD, Open Loop Acceleration, Current Ramp Down and Coasting. Each one of these steps are executed if the condition shown below the step evaluates to TRUE; if the condition evaluates to FALSE, the algorithm bypasses that particular step and moves on to the next step in the sequence. Once all the 4 steps are completed (or bypassed), the algorithm exits the MPET routine. If target speed is set to a non-zero value, the algorithm begins the start-up and acceleration sequence (to target speed reference) once MPET routine is exited.

MCF8316D MPET SequenceFigure 6-49 MPET Sequence

TI proprietary MPET routine includes following sequence of operation.

  • IPD: The MPET routine starts with IPD, if the user enables motor winding resistance or inductance measurement by setting MPET_R = 1b and MPET_L = 1b or if the user defines MOTOR_RES = 0 or MOTOR_IND = 0. The IPD during MPET is configured using the normal motor operation IPD configuration parameters. The IPD current limit and the repeat number is configured using IPD_CURR_THR and IPD_REPEAT. The IPD timer over flow or the IPD current decay time more than three times the current ramp up time can result in MPET_IPD_FAULT.
  • Open loop Acceleration:

    After IPD, the MPET routine runs align and then open loop acceleration if the back-EMF constant or mechanical parameter measurement are enabled by setting MPET_KE = 1b and MPET_MECH = 1b. The MPET routine incorporates the sequences for mechanical parameter measurement, if the speed loop PI constants are defined as zero, even if MPET_MECH = 0b. This routine uses normal motor operation open loop configuration parameters. The speed slew rate is set by OL_ACC_A1 and OL_ACC_A2, current reference is set by OL_ILIMIT and speed reference is set by OPN_CL_HANDOFF_THR.

  • Current Ramp Down: After open loop acceleration, if the mechanical parameter measurement is enabled, then the MPET routine optimizes the motor current to lower value sufficient to support the load. If mechanical parameter measurement is disabled (MPET_MECH = 0b, or non-zero speed loop PI parameters) then the MPET will not have the current ramp down sequence.
  • Coasting: MPET routine completes the sequence by allowing the motor to coast by enabling Hi-Z. The motor back EMF and indicative values of mechanical parameters are measured during the motor coasting period. If the motor back EMF is lower than the threshold defined in STAT_DETECT_THR, the MPET_BEMF_FAULT is generated.

Note: User can exit the MPET routine at any time by writing 0b to MPET_CMD bit and by making target speed as zero.

Selecting the parameters from EEPROM or MPET

The MPET estimated values are available in the MTR_PARAMS Register. Setting the MPET_WRITE_SHADOW bit to 1, writes the MPET estimated values to the shadow/RAM registers and the user-configured (from EEPROM) values in MOTOR_RES, MOTOR_IND, MOTOR_BEMF_CONST, CURR_LOOP_KP, CURR_LOOP_KI, SPD_LOOP_KP and SPD_LOOP_KI shadow/RAM registers will be overwritten by the estimated values from MPET. If any of the shadow/RAM registers are initialized to zero (from EEPROM registers), the MPET estimated values are used for those registers independent of the MPET_WRITE_SHADOW setting. The MPET calculates the current loop KP and KI by using the measured resistance and inductance. The MPET does an estimation of the mechanical parameters including the inertia and frictional coefficient at the shaft (includes both motor and shaft coupled load). These values are used to set an initial values speed loop KP and KI. The estimated speed loop KP and KI setting can be used as an initial setting only and TI recommends to tune these parameters on application by the user based on the performance requirement.