SLVSH53 December   2023 MCT8315Z

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 SPI Timing Requirements
    7. 7.7 SPI Secondary Device Mode Timings
    8. 7.8 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Output Stage
      2. 8.3.2  PWM Control Mode (1x PWM Mode)
        1. 8.3.2.1 Analog Hall Input Configuration
        2. 8.3.2.2 Digital Hall Input Configuration
        3. 8.3.2.3 Asynchronous Modulation
        4. 8.3.2.4 Synchronous Modulation
        5. 8.3.2.5 Motor Operation
      3. 8.3.3  Device Interface Modes
        1. 8.3.3.1 Serial Peripheral Interface (SPI)
        2. 8.3.3.2 Hardware Interface
      4. 8.3.4  Step-Down Mixed-Mode Buck Regulator
        1. 8.3.4.1 Buck in Inductor Mode
        2. 8.3.4.2 Buck in Resistor mode
        3. 8.3.4.3 Buck Regulator with External LDO
        4. 8.3.4.4 AVDD Power Sequencing on Buck Regulator
        5. 8.3.4.5 Mixed mode Buck Operation and Control
      5. 8.3.5  AVDD Linear Voltage Regulator
      6. 8.3.6  Charge Pump
      7. 8.3.7  Slew Rate Control
      8. 8.3.8  Cross Conduction (Dead Time)
      9. 8.3.9  Propagation Delay
        1. 8.3.9.1 Driver Delay Compensation
      10. 8.3.10 Pin Diagrams
        1. 8.3.10.1 Logic Level Input Pin (Internal Pulldown)
        2. 8.3.10.2 Logic Level Input Pin (Internal Pullup)
        3. 8.3.10.3 Open Drain Pin
        4. 8.3.10.4 Push Pull Pin
        5. 8.3.10.5 Four Level Input Pin
        6. 8.3.10.6 Seven Level Input Pin
      11. 8.3.11 Active Demagnetization
        1. 8.3.11.1 Automatic Synchronous Rectification Mode (ASR Mode)
          1. 8.3.11.1.1 Automatic Synchronous Rectification in Commutation
          2. 8.3.11.1.2 Automatic Synchronous Rectification in PWM Mode
        2. 8.3.11.2 Automatic Asynchronous Rectification Mode (AAR Mode)
      12. 8.3.12 Cycle-by-Cycle Current Limit
        1. 8.3.12.1 Cycle by Cycle Current Limit with 100% Duty Cycle Input
      13. 8.3.13 Hall Comparators (Analog Hall Inputs)
      14. 8.3.14 Advance Angle
      15. 8.3.15 FGOUT Signal
      16. 8.3.16 Protections
        1. 8.3.16.1  VM Supply Undervoltage Lockout (NPOR)
        2. 8.3.16.2  AVDD Undervoltage Lockout (AVDD_UV)
        3. 8.3.16.3  Buck Undervoltage Lockout (BUCK_UV)
        4. 8.3.16.4  VCP Charge Pump Undervoltage Lockout (CPUV)
        5. 8.3.16.5  Overvoltage Protection (OVP)
        6. 8.3.16.6  Overcurrent Protection (OCP)
          1. 8.3.16.6.1 OCP Latched Shutdown (OCP_MODE = 00b)
          2. 8.3.16.6.2 OCP Automatic Retry (OCP_MODE = 01b)
        7. 8.3.16.7  Buck Overcurrent Protection
        8. 8.3.16.8  Motor Lock (MTR_LOCK)
          1. 8.3.16.8.1 MTR_LOCK Latched Shutdown (MTR_LOCK_MODE = 00b)
          2. 8.3.16.8.2 MTR_LOCK Automatic Retry (MTR_LOCK_MODE = 01b)
          3. 8.3.16.8.3 MTR_LOCK Report Only (MTR_LOCK_MODE= 10b)
          4. 8.3.16.8.4 MTR_LOCK Disabled (MTR_LOCK_MODE = 11b)
          5. 8.3.16.8.5 75
        9. 8.3.16.9  Thermal Warning (OTW)
        10. 8.3.16.10 Thermal Shutdown (OTSD)
          1. 8.3.16.10.1 OTSD FET
          2. 8.3.16.10.2 OTSD (Non-FET)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Functional Modes
        1. 8.4.1.1 Sleep Mode
        2. 8.4.1.2 Operating Mode
        3. 8.4.1.3 Fault Reset (CLR_FLT or nSLEEP Reset Pulse)
      2. 8.4.2 DRVOFF
    5. 8.5 SPI Communication
      1. 8.5.1 Programming
        1. 8.5.1.1 SPI Format
    6. 8.6 Register Map
      1. 8.6.1 STATUS Registers
      2. 8.6.2 CONTROL Registers
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Hall Sensor Configuration and Connection
      1. 9.2.1 Typical Configuration
      2. 9.2.2 Open Drain Configuration
      3. 9.2.3 Series Configuration
      4. 9.2.4 Parallel Configuration
    3. 9.3 Typical Applications
      1. 9.3.1 Three-Phase Brushless-DC Motor Control With Current Limit
        1. 9.3.1.1 Detailed Design Procedure
          1. 9.3.1.1.1 Motor Voltage
          2. 9.3.1.1.2 Using Active Demagnetization
          3. 9.3.1.1.3 Using Delay Compensation
          4. 9.3.1.1.4 Using the Buck Regulator
          5. 9.3.1.1.5 Power Dissipation and Junction Temperature Losses
        2. 9.3.1.2 Application Curves
  11. 10Power Supply Recommendations
    1. 10.1 Bulk Capacitance
  12. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Thermal Considerations
      1. 11.3.1 Power Dissipation
  13. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  14. 13Mechanical, Packaging, and Orderable Information

Package Options

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

11.1 Layout Guidelines

The bulk capacitor should be placed to minimize the distance of the high-current path through the motor driver device. The connecting metal trace widths should be as wide as possible, and numerous vias should be used when connecting PCB layers. These practices minimize inductance and allow the bulk capacitor to deliver high current.

Small-value capacitors such as the charge pump, AVDD, and VREF capacitors should be ceramic and placed closely to device pins.

The high-current device outputs should use wide metal traces.

To reduce noise coupling and EMI interference from large transient currents into small-current signal paths, grounding should be partitioned between PGND and AGND. TI recommends connecting all non-power stage circuitry (including the thermal pad) to AGND to reduce parasitic effects and improve power dissipation from the device. Optionally, GND_BK can be split. Make sure grounds are connected through net-ties or wide resistors to reduce voltage offsets and maintain gate driver performance.

The device thermal pad should be soldered to the PCB top-layer ground plane. Multiple vias should be used to connect to a large bottom-layer ground plane. The use of large metal planes and multiple vias help dissipate the power loss that is generated in the device.

To improve thermal performance, maximize the ground area that is connected to the thermal pad ground across all possible layers of the PCB. Using thick copper pours can lower the junction-to-air thermal resistance and improve thermal dissipation from the die surface.

Separate the SW_BK and FB_BK traces with ground separation to reduce buck switching from coupling as noise into the buck outer feedback loop. Widen the FB_BK trace as much as possible to allow for faster load switching.

Figure 11-1 shows a layout example for the MCT8315Z.