SLLSFP6A December   2022  – April 2023 MCF8315A

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
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    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  Output Stage
      2. 7.3.2  Device Interface
        1. 7.3.2.1 Interface - Control and Monitoring
        2. 7.3.2.2 I2C Interface
      3. 7.3.3  Step-Down Mixed-Mode Buck Regulator
        1. 7.3.3.1 Buck in Inductor Mode
        2. 7.3.3.2 Buck in Resistor mode
        3. 7.3.3.3 Buck Regulator with External LDO
        4. 7.3.3.4 AVDD Power Sequencing from Buck Regulator
        5. 7.3.3.5 Mixed Mode Buck Operation and Control
        6. 7.3.3.6 Buck Under Voltage Protection
        7. 7.3.3.7 Buck Over Current Protection
      4. 7.3.4  AVDD Linear Voltage Regulator
      5. 7.3.5  Charge Pump
      6. 7.3.6  Slew Rate Control
      7. 7.3.7  Cross Conduction (Dead Time)
      8. 7.3.8  Speed Control
        1. 7.3.8.1 Analog Mode Speed Control
        2. 7.3.8.2 PWM Mode Speed Control
        3. 7.3.8.3 I2C based Speed Control
        4. 7.3.8.4 Frequency Mode Speed Control
        5. 7.3.8.5 Speed Profiles
          1. 7.3.8.5.1 Linear Speed Profiles
          2. 7.3.8.5.2 Staircase Speed Profile
          3. 7.3.8.5.3 Forward-Reverse Speed Profile
      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 Mode
            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 Overmodulation
      12. 7.3.12 Motor Parameters
        1. 7.3.12.1 Motor Resistance
        2. 7.3.12.2 Motor Inductance
        3. 7.3.12.3 Motor Back-EMF constant
      13. 7.3.13 Motor Parameter Extraction Tool (MPET)
      14. 7.3.14 Anti-Voltage Surge (AVS)
      15. 7.3.15 Output PWM Switching Frequency
      16. 7.3.16 Active Braking
      17. 7.3.17 PWM Modulation Schemes
      18. 7.3.18 Dead Time Compensation
      19. 7.3.19 Motor Stop Options
        1. 7.3.19.1 Coast (Hi-Z) Mode
        2. 7.3.19.2 Recirculation Mode
        3. 7.3.19.3 Low-Side Braking
        4. 7.3.19.4 High-Side Braking
        5. 7.3.19.5 Active Spin-Down
        6. 7.3.19.6 Align Braking
      20. 7.3.20 FG Configuration
        1. 7.3.20.1 FG Output Frequency
        2. 7.3.20.2 FG Open-Loop and Lock Behavior
      21. 7.3.21 DC Bus Current Limit
      22. 7.3.22 Protections
        1. 7.3.22.1  VM Supply Undervoltage Lockout
        2. 7.3.22.2  AVDD Undervoltage Lockout (AVDD_UV)
        3. 7.3.22.3  BUCK Undervoltage Lockout (BUCK_UV)
        4. 7.3.22.4  VCP Charge Pump Undervoltage Lockout (CPUV)
        5. 7.3.22.5  Overvoltage Protection (OVP)
        6. 7.3.22.6  Overcurrent Protection (OCP)
          1. 7.3.22.6.1 OCP Latched Shutdown (OCP_MODE = 00b)
          2. 7.3.22.6.2 OCP Automatic Retry (OCP_MODE = 01b)
          3. 7.3.22.6.3 OCP Report Only (OCP_MODE = 10b)
          4. 7.3.22.6.4 OCP Disabled (OCP_MODE = 11b)
        7. 7.3.22.7  Buck Overcurrent Protection
        8. 7.3.22.8  Hardware Lock Detection Current Limit (HW_LOCK_ILIMIT)
          1. 7.3.22.8.1 HW_LOCK_ILIMIT Latched Shutdown (HW_LOCK_ILIMIT_MODE = 00xxb)
          2. 7.3.22.8.2 HW_LOCK_ILIMIT Automatic recovery (HW_LOCK_ILIMIT_MODE = 01xxb)
          3. 7.3.22.8.3 HW_LOCK_ILIMIT Report Only (HW_LOCK_ILIMIT_MODE = 1000b)
          4. 7.3.22.8.4 HW_LOCK_ILIMIT Disabled (HW_LOCK_ILIMIT_MODE= 1xx1b)
        9. 7.3.22.9  Thermal Warning (OTW)
        10. 7.3.22.10 Thermal Shutdown (TSD)
        11. 7.3.22.11 Motor Lock (MTR_LCK)
          1. 7.3.22.11.1 MTR_LCK Latched Shutdown (MTR_LCK_MODE = 00xxb)
          2. 7.3.22.11.2 MTR_LCK Automatic Recovery (MTR_LCK_MODE= 01xxb)
          3. 7.3.22.11.3 MTR_LCK Report Only (MTR_LCK_MODE = 1000b)
          4. 7.3.22.11.4 MTR_LCK Disabled (MTR_LCK_MODE = 1xx1b)
        12. 7.3.22.12 Motor Lock Detection
          1. 7.3.22.12.1 Lock 1: Abnormal Speed (ABN_SPEED)
          2. 7.3.22.12.2 Lock 2: Abnormal BEMF (ABN_BEMF)
          3. 7.3.22.12.3 Lock3: No-Motor Fault (NO_MTR)
        13. 7.3.22.13 MPET Faults
        14. 7.3.22.14 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 Functionality
      2. 7.5.2 DAC outputs
      3. 7.5.3 Current Sense Output
      4. 7.5.4 Oscillator Source
        1. 7.5.4.1 External Clock Source
      5. 7.5.5 External Watchdog
    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 Transaction
        3. 7.6.2.3 I2C Read Transaction
        4. 7.6.2.4 I2C Communication Protocol Packet Examples
        5. 7.6.2.5 I2C Clock Stretching
        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 Fault_Configuration Registers
      3. 7.7.3 Hardware_Configuration Registers
      4. 7.7.4 Internal_Algorithm_Configuration Registers
    8. 7.8 RAM (Volatile) Register Map
      1. 7.8.1 Fault_Status Registers
      2. 7.8.2 System_Status Registers
      3. 7.8.3 Device_Control Registers
      4. 7.8.4 Algorithm_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. 8.2.1 Speed Input before VM Power-up
      2. 8.2.2 Application Curves
        1. 8.2.2.1 Motor startup
        2. 8.2.2.2 MPET
        3. 8.2.2.3 Dead time compensation
        4. 8.2.2.4 Auto handoff
        5. 8.2.2.5 Motor stop – recirculation mode
        6. 8.2.2.6 Anti voltage surge (AVS)
        7. 8.2.2.7 Real time variable tracking using DACOUT
  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 Support Resources
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
7.3.10.4.6 Transition from Open to Closed Loop

Once the motor has reached a sufficient speed for the back-EMF observer to estimate the angle and speed of the motor, the MCF8315A transitions into closed loop state. This handoff speed is automatically determined based on the measured back-EMF and motor speed. Users also have an option to manually set the handoff speed by configuring OPN_CL_HANDOFF_THR and setting AUTO_HANDOFF_EN to 0b. In order to have smooth transition and avoid speed transients, the theta_error (Ɵgen - Ɵest) is decreased linearly after transition. The ramp rate of theta_error reduction can be configured using THETA_ERROR_RAMP_RATE. If the current limit set during the open loop is high and if it is not reduced before transition to closed loop, the motor speed may momentarily rise to higher values than SPEED_REF after transition into closed loop. In order to avoid such speed variations, configure the IQ_RAMP_EN to 1b, so that iq_ref decreases prior to transition into closed loop. However if the final speed reference (SPEED_REF) is more than two times the open loop to closed loop hand off speed (OPN_CL_HANDOFF_THR), then iq_ref is not decreased independent of the IQ_RAMP_EN setting, to enable faster motor acceleration.

After hand off to closed loop at a sufficient speed, there could be still some theta error, as the estimators may not be fully aligned. A slow acceleration can be used after the open loop to closed loop transition, ensuring that the theta error reduces to zero. The slow acceleration can be configured using CL_SLOW_ACC.

Figure 7-52 shows the control sequence in open to closed loop transition. The current iq_ref reduces to a lower value in current decay region, if IQ_RAMP_EN is set to 1b. If IQ_RAMP_EN is set to 0b, then the current decay region will not be present in the transition sequence.

GUID-2A71A7FA-FC98-419E-BA03-D3E2B8F6FDC0-low.svgFigure 7-31 Control Sequence in Open to Closed Loop Transition
GUID-CC7CB416-3B86-4D60-BCDE-79ED31C455E8-low.svgFigure 7-32 Open to Closed Loop Transition Control Block Diagram