SLLSFQ7 November   2023 MCF8329A

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings Comm
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information 1pkg
    5. 6.5 Electrical Characteristics
    6. 6.6 Characteristics of the SDA and SCL bus for Standard and Fast mode
    7. 6.7 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Three Phase BLDC Gate Drivers
      2. 7.3.2  Gate Drive Architecture
        1. 7.3.2.1 Dead time and Cross Conduction Prevention
      3. 7.3.3  AVDD Linear Voltage Regulator
      4. 7.3.4  DVDD Voltage Regulator
        1. 7.3.4.1 AVDD Powered VREG
        2. 7.3.4.2 External Supply for VREG
        3. 7.3.4.3 External MOSFET for VREG Supply
      5. 7.3.5  Low-Side Current Sense Amplifier
      6. 7.3.6  Device Interface Modes
        1. 7.3.6.1 Interface - Control and Monitoring
        2. 7.3.6.2 I2C Interface
      7. 7.3.7  Motor Control Input Options
        1. 7.3.7.1 Analog-Mode Motor Control
        2. 7.3.7.2 PWM-Mode Motor Control
        3. 7.3.7.3 Frequency-Mode Motor Control
        4. 7.3.7.4 I2C based Motor Control
        5. 7.3.7.5 Input Control Reference Profiles
          1. 7.3.7.5.1 Linear Control Profiles
          2. 7.3.7.5.2 Staircase Control Profiles
          3. 7.3.7.5.3 Forward-Reverse Profiles
        6. 7.3.7.6 Control Input Transfer Function without Profiler
      8. 7.3.8  Bootstrap Capacitor Initial Charging
      9. 7.3.9  Starting the Motor Under Different Initial Conditions
        1. 7.3.9.1 Case 1 – Motor is Stationary
        2. 7.3.9.2 Case 2 – Motor is Spinning in the Forward Direction
        3. 7.3.9.3 Case 3 – Motor is Spinning in the Reverse Direction
      10. 7.3.10 Motor Start Sequence (MSS)
        1. 7.3.10.1 Initial Speed Detect (ISD)
        2. 7.3.10.2 Motor Resynchronization
        3. 7.3.10.3 Reverse Drive
          1. 7.3.10.3.1 Reverse Drive Tuning
        4. 7.3.10.4 Motor Start-up
          1. 7.3.10.4.1 Align
          2. 7.3.10.4.2 Double Align
          3. 7.3.10.4.3 Initial Position Detection (IPD)
            1. 7.3.10.4.3.1 IPD Operation
            2. 7.3.10.4.3.2 IPD Release
            3. 7.3.10.4.3.3 IPD Advance Angle
          4. 7.3.10.4.4 Slow First Cycle Startup
          5. 7.3.10.4.5 Open loop
          6. 7.3.10.4.6 Transition from Open to Closed Loop
      11. 7.3.11 Closed Loop Operation
        1. 7.3.11.1 Closed loop accelerate
        2. 7.3.11.2 Speed PI Control
        3. 7.3.11.3 Current PI Control
        4. 7.3.11.4 Power Loop
        5. 7.3.11.5 Modulation Index Control
      12. 7.3.12 Maximum Torque Per Ampere (MTPA) Control
      13. 7.3.13 Flux Weakening Control
      14. 7.3.14 Motor Parameters
        1. 7.3.14.1 Motor Resistance
        2. 7.3.14.2 Motor Inductance
        3. 7.3.14.3 Motor Back-EMF constant
      15. 7.3.15 Motor Parameter Extraction Tool (MPET)
      16. 7.3.16 Anti-Voltage Surge (AVS)
      17. 7.3.17 Output PWM Switching Frequency
      18. 7.3.18 Active Braking
      19. 7.3.19 Dead Time Compensation
      20. 7.3.20 Voltage Sense Scaling
      21. 7.3.21 Motor Stop Options
        1. 7.3.21.1 Coast (Hi-Z) Mode
        2. 7.3.21.2 Recirculation Mode
        3. 7.3.21.3 Low-Side Braking
        4. 7.3.21.4 Active Spin-Down
      22. 7.3.22 FG Configuration
        1. 7.3.22.1 FG Output Frequency
        2. 7.3.22.2 FG in Open-Loop
        3. 7.3.22.3 FG During Motor Stop
        4. 7.3.22.4 FG Behaviour During Fault
      23. 7.3.23 DC Bus Current Limit
      24. 7.3.24 Protections
        1. 7.3.24.1  PVDD Supply Undervoltage Lockout (PVDD_UV)
        2. 7.3.24.2  AVDD Power on Reset (AVDD_POR)
        3. 7.3.24.3  GVDD Undervoltage Lockout (GVDD_UV)
        4. 7.3.24.4  BST Undervoltage Lockout (BST_UV)
        5. 7.3.24.5  MOSFET VDS Overcurrent Protection (VDS_OCP)
        6. 7.3.24.6  VSENSE Overcurrent Protection (SEN_OCP)
        7. 7.3.24.7  Thermal Shutdown (OTSD)
        8. 7.3.24.8  Hardware Lock Detection Current Limit (HW_LOCK_ILIMIT)
          1. 7.3.24.8.1 HW_LOCK_ILIMIT Latched Shutdown (HW_LOCK_ILIMIT_MODE = 00xxb)
          2. 7.3.24.8.2 HW_LOCK_ILIMIT Automatic recovery (HW_LOCK_ILIMIT_MODE = 01xxb)
          3. 7.3.24.8.3 HW_LOCK_ILIMIT Report Only (HW_LOCK_ILIMIT_MODE = 1000b)
          4. 7.3.24.8.4 HW_LOCK_ILIMIT Disabled (HW_LOCK_ILIMIT_MODE= 1001b to 1111b)
        9. 7.3.24.9  Lock Detection Current Limit (LOCK_ILIMIT)
          1. 7.3.24.9.1 LOCK_ILIMIT Latched Shutdown (LOCK_ILIMIT_MODE = 00xxb)
          2. 7.3.24.9.2 LOCK_ILIMIT Automatic Recovery (LOCK_ILIMIT_MODE = 01xxb)
          3. 7.3.24.9.3 LOCK_ILIMIT Report Only (LOCK_ILIMIT_MODE = 1000b)
          4. 7.3.24.9.4 LOCK_ILIMIT Disabled (LOCK_ILIMIT_MODE = 1xx1b)
        10. 7.3.24.10 Motor Lock (MTR_LCK)
          1. 7.3.24.10.1 MTR_LCK Latched Shutdown (MTR_LCK_MODE = 00xxb)
          2. 7.3.24.10.2 MTR_LCK Automatic Recovery (MTR_LCK_MODE= 01xxb)
          3. 7.3.24.10.3 MTR_LCK Report Only (MTR_LCK_MODE = 1000b)
          4. 7.3.24.10.4 MTR_LCK Disabled (MTR_LCK_MODE = 1xx1b)
        11. 7.3.24.11 Motor Lock Detection
          1. 7.3.24.11.1 Lock 1: Abnormal Speed (ABN_SPEED)
          2. 7.3.24.11.2 Lock 2: Abnormal BEMF (ABN_BEMF)
          3. 7.3.24.11.3 Lock3: No-Motor Fault (NO_MTR)
        12. 7.3.24.12 MPET Faults
        13. 7.3.24.13 IPD Faults
    4. 7.4 Device Functional Modes
      1. 7.4.1 Functional Modes
        1. 7.4.1.1 Sleep Mode
        2. 7.4.1.2 Standby Mode
        3. 7.4.1.3 Fault Reset (CLR_FLT)
    5. 7.5 External Interface
      1. 7.5.1 DRVOFF - Gate Driver Shutdown Functionality
      2. 7.5.2 DAC outputs
      3. 7.5.3 Current Sense Amplifier Output
      4. 7.5.4 Oscillator Source
        1. 7.5.4.1 External Clock Source
    6. 7.6 EEPROM access and I2C interface
      1. 7.6.1 EEPROM Access
        1. 7.6.1.1 EEPROM Write
        2. 7.6.1.2 EEPROM Read
      2. 7.6.2 I2C Serial Interface
        1. 7.6.2.1 I2C Data Word
        2. 7.6.2.2 I2C Write Operation
        3. 7.6.2.3 I2C Read Operation
        4. 7.6.2.4 Examples of I2C Communication Protocol Packets
        5. 7.6.2.5 Internal Buffers
        6. 7.6.2.6 CRC Byte Calculation
    7. 7.7 EEPROM (Non-Volatile) Register Map
      1. 7.7.1 Algorithm_Configuration Registers
      2. 7.7.2 Internal_Algorithm_Configuration Registers
      3. 7.7.3 Hardware_Configuration Registers
      4. 7.7.4 Fault_Configuration Registers
    8. 7.8 RAM (Volatile) Register Map
      1. 7.8.1 Fault_Status Registers
      2. 7.8.2 Algorithm_Control Registers
      3. 7.8.3 System_Status Registers
      4. 7.8.4 Device_Control Registers
      5. 7.8.5 Algorithm_Variables Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1.      Detailed Design Procedure
      2.      Bootstrap Capacitor and GVDD Capacitor Selection
      3. 8.2.1 Selection of External MOSFET for VREG Power Supply
      4.      Gate Drive Current
      5.      Gate Resistor Selection
      6.      System Considerations in High Power Designs
      7.      Capacitor Voltage Ratings
      8.      External Power Stage Components
      9. 8.2.2 Application curves
        1. 8.2.2.1 Motor startup
        2.       High speed (1.8 kHz) operation
        3.       Active Braking for faster deceleration
        4. 8.2.2.2 Dead Time compensation
  10. 9 Power Supply Recommendations
    1. 9.1 Bulk Capacitance
  11. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
      1. 10.3.1 Power Dissipation
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.15 Motor Parameter Extraction Tool (MPET)

The MCF8329A uses motor winding resistance, motor winding inductance and Back-EMF constant to estimate motor position in closed loop operation. The MPET routine measures motor 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 start-up to minimize the impact caused due to possible parameter variations.

Figure 7-38 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 in Figure 7-38 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 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.

GUID-20230305-SS0I-SSCB-D9LJ-GPVHKKS8BPLW-low.svg Figure 7-38 MPET Sequence

TI proprietary MPET routine includes following sequence of operation.

  • Open loop Acceleration: The MPET routine run 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. User can configure MPET specific open loop configuration parameters or use normal motor operation open loop configuration parameters. The open loop configuration selection is done using MPET_KE_MEAS_PARAMETER_SELECT. With MPET_KE_MEAS_PARAMETER_SELECT = 1b, the speed slew rate is defined using MPET_OPEN_LOOP_SLEW_RATE, the open loop current reference is defined using MPET_OPEN_LOOP_CURR_REF and the open loop speed reference is defined using MPET_OPEN_LOOP_SPEED_REF. With MPET_KE_MEAS_PARAMETER_SELECT = 0b, the speed slew rate is defined using OL_ACC_A1 and OL_ACC_A2, the current reference is OL_ILIMIT, and speed ref is OPN_CL_HANDOFF_THR speed.
  • 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.

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 registers and the user-configured (from EEPROM) values in MOTOR_BEMF_CONST, SPD_LOOP_KP and SPD_LOOP_KI shadow registers will be overwritten by the estimated values from MPET. If any of the shadow 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 user entered 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.

Note:
  1. TI recommends to set the bit VdcFilterDisable to 1b during MPET measurement.
  2. FG signal is not accurate during MPET.
  3. If CURRENT_LOOP_KP and CURRENT_LOOP_KI are set to zero, then MCF8329A automatically calculate these coefficients using motor resistance and inductance values.