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

8.2 Typical Applications

Figure 8-1 shows the typical schematic of MCF8315A

GUID-20220829-SS0I-ZPF8-FV5F-SMP51NV3NXGD-low.svg Figure 8-1 Example Application Schematic

Table 8-1 lists the recommended values of the external components for MCF8315A.

Table 8-1 MCF8315A External Components
COMPONENTS PIN 1 PIN 2 RECOMMENDED
CVM1 VM PGND X5R or X7R, 0.1-µF, TI recommends a capacitor voltage rating at least twice the normal operating voltage of the device
CVM2 VM PGND ≥ 10-µF, TI recommends a capacitor voltage rating at least twice the normal operating voltage of the device
CCP CP VM X5R or X7R, 16-V, 1-µF capacitor
CFLY CPH CPL X5R or X7R, 47-nF, TI recommends a capacitor voltage rating at least twice the normal operating voltage of the pin
CAVDD AVDD AGND X5R or X7R, 1-µF, ≥ 6.3-V. In order for AVDD to accurately regulate output voltage, capacitor should have effective capacitance between 0.7-µF to 1.3-µF at 3.3-V across operating temperature.
CDVDD DVDD DGND X5R or X7R, 2.2-µF, ≥ 6.3-V. In order for DVDD to accurately regulate output voltage, capacitor should have effective capacitance between 1.1-µF to 2.5-µF at 1.5-V across operating temperature.
CBK FB_BK GND_BK X5R or X7R, buck-output rated capacitor
LBK SW_BK FB_BK Buck-output inductor
RFG 1.8 to 5-V Supply FG 5.1-kΩ, Pull-up resistor
RnFAULT 1.8 to 5-V Supply nFAULT 5.1-kΩ, Pull-up resistor
RSDA 1.8 to 3.3-V Supply SDA 5.1-kΩ, Pull-up resistor
RSCL 1.8 to 3.3-V Supply SCL 5.1-kΩ, Pull-up resistor
Recommended application range for MCF8315A is shown in Table 8-2.
Table 8-2 Recommended Application Range
Parameter Min Max Unit
Motor voltage 4.5 35 V
Back-EMF constant (see Section 7.3.12.3) 0.6 2000 mV/Hz
Motor resistance (see Section 7.3.12.1) 0.006 20 Ω
Motor inductance (see Section 7.3.12.2) 0.006 20 mH
Motor electrical speed - 1500 Hz
Peak motor phase current - 4 A

Default EEPROM configuration for MCF8315A is listed in Table 8-3. Default values are chosen for reliable motor start-up and closed loop operation. Refer to MCF8315A tuning guide which provides step by step procedure to tune a 3-phase BLDC motor in closed loop, conform to use-case and explore features in the device.

Table 8-3 Recommended Default Values

Address Name

Address

Recommended Value
ISD_CONFIG 0x00000080 0x64738C20
REV_DRIVE_CONFIG 0x00000082 0x28200000
MOTOR_STARTUP1 0x00000084 0x0B6807D0
MOTOR_STARTUP2 0x00000086 0x2306600C
CLOSED_LOOP1 0x00000088 0x0D3201B4
CLOSED_LOOP2 0x0000008A 0x0BAD0000
CLOSED_LOOP3 0x0000008C 0x00000000
CLOSED_LOOP4 0x0000008E 0x00000000
SPEED_PROFILES1 0x00000094 0x00000000
SPEED_PROFILES2 0x00000096 0x00000000
SPEED_PROFILES3 0x00000098 0x00000000
SPEED_PROFILES4 0x0000009A 0x000D0000
SPEED_PROFILES5 0x0000009C 0x00000000
SPEED_PROFILES6 0x0000009E 0x00000000
FAULT_CONFIG1 0x00000090 0x3EC80106
FAULT_CONFIG2 0x00000092 0x70D00888
PIN_CONFIG 0x000000A4 0x00000000
DEVICE_CONFIG1 0x000000A6 0x00101462
DEVICE_CONFIG2 0x000000A8 0x4000F00F
PERI_CONFIG1 0x000000AA 0x41C05F00
GD_CONFIG1 0x000000AC 0x1C450100
GD_CONFIG2 0x000000AE 0x00200000
INT_ALGO_1 0x000000A0 0x2433407D
INT_ALGO_2 0x000000A2 0x000001A7

Once the device EEPROM is programmed with the desired configuration, device can be operated stand-alone and I2C serial interface is not required anymore. Speed can be commanded using SPEED pin.

Below are the two essential parameters that are required to spin the motor in closed loop.

  1. Maximum motor speed.
  2. Current limit for torque PI loop.