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

7.1 Overview

The MCF8315A provides a single-chip, code-free sensorless FOC solution for customers driving speed-controlled 12- to 24-V brushless-DC motors requiring up to 4-A peak phase currents.

The MCF8315A integrates three ½-bridges with 40-V absolute maximum capability and a low RDS(ON) of 240-mΩ (high-side + low-side) to enable high power drive capability. Current is sensed using an integrated current sensing circuit which eliminates the need for external sense resistors. Power management features of an adjustable buck regulator and LDO generate the necessary voltage rails for the device and can also be used to power external circuits.

MCF8315A implements Sensorless FOC, and so an external microcontroller is not required to spin the brushless-DC motor. The algorithm is implemented in a fixed-function state machine, so no coding is needed. The algorithm is highly configurable through register settings ranging from motor start-up behavior to closed loop operation. Register settings can be stored in non-volatile EEPROM, which allows the device to operate stand-alone once it has been configured. The device receives a speed command through a PWM input, analog voltage, frequency input or I2C command.

In-built protection features include power-supply under voltage lockout (UVLO), charge-pump under voltage lockout (CPUV), over current protection (OCP), AVDD under voltage lockout (AVDD_UV), buck regulator UVLO, motor lock detection and over temperature warning and shutdown (OTW and TSD). Fault events are indicated by the nFAULT pin with detailed fault information available in the registers.

The MCF8315A device is available in a 0.5-mm pin pitch, VQFN surface-mount package. The VQFN package size is 7 mm × 5 mm with a height of 1 mm.