SLVSDY7B October   2017  – January 2021 DRV8873-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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 SPI Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Bridge Control
        1. 7.3.1.1 Control Modes
        2. 7.3.1.2 Half-Bridge Operation
        3. 7.3.1.3 22
        4. 7.3.1.4 Internal Current Sense and Current Regulation
        5. 7.3.1.5 Slew-Rate Control
        6. 7.3.1.6 Dead Time
        7. 7.3.1.7 Propagation Delay
        8. 7.3.1.8 nFAULT Pin
        9. 7.3.1.9 nSLEEP as SDO Reference
      2. 7.3.2 Motor Driver Protection Circuits
        1. 7.3.2.1 VM Undervoltage Lockout (UVLO)
        2. 7.3.2.2 VCP Undervoltage Lockout (CPUV)
        3. 7.3.2.3 Overcurrent Protection (OCP)
          1. 7.3.2.3.1 Latched Shutdown (OCP_MODE = 00b)
          2. 7.3.2.3.2 Automatic Retry (OCP_MODE = 01b)
          3. 7.3.2.3.3 Report Only (OCP_MODE = 10b)
          4. 7.3.2.3.4 Disabled (OCP_MODE = 11b)
        4. 7.3.2.4 Open-Load Detection (OLD)
          1. 7.3.2.4.1 Open-Load Detection in Passive Mode (OLP)
          2. 7.3.2.4.2 Open-Load Detection in Active Mode (OLA)
        5. 7.3.2.5 Thermal Shutdown (TSD)
          1. 7.3.2.5.1 Latched Shutdown (TSD_MODE = 0b)
          2. 7.3.2.5.2 Automatic Recovery (TSD_MODE = 1b)
        6. 7.3.2.6 Thermal Warning (OTW)
      3. 7.3.3 Hardware Interface
        1. 7.3.3.1 MODE (Tri-Level Input)
        2. 7.3.3.2 Slew Rate
    4. 7.4 Device Functional Modes
      1. 7.4.1 Motor Driver Functional Modes
        1. 7.4.1.1 Sleep Mode (nSLEEP = 0)
        2. 7.4.1.2 Disable Mode (nSLEEP = 1, DISABLE = 1)
        3. 7.4.1.3 Operating Mode (nSLEEP = 1, DISABLE = 0)
        4. 7.4.1.4 nSLEEP Reset Pulse
    5. 7.5 Programming
      1. 7.5.1 Serial Peripheral Interface (SPI) Communication
        1. 7.5.1.1 SPI Format
        2. 7.5.1.2 SPI for a Single Slave Device
        3. 7.5.1.3 SPI for Multiple Slave Devices in Parallel Configuration
        4. 7.5.1.4 SPI for Multiple Slave Devices in Daisy Chain Configuration
    6. 7.6 Register Maps
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
        1. 8.2.1.1 Motor Voltage
        2. 8.2.1.2 Drive Current and Power Dissipation
        3. 8.2.1.3 Sense Resistor
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Thermal Considerations
        2. 8.2.2.2 Heatsinking
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
    1. 9.1 Bulk Capacitance Sizing
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.5.1.2 SPI for a Single Slave Device

The SPI is used to set device configurations, operating parameters, and read out diagnostic information. The device SPI operates in slave mode. The SPI input-data (SDI) word consists of a 16-bit word, with 8 bits command and 8 bits of data. The SPI output data (SDO) word consists of 8 bits of status register with fault status indication and 8 bits of register data. Figure 7-15 shows the data sequence between the MCU and the SPI slave driver.

GUID-93887A20-869C-4B65-98D0-54661E905F9F-low.gifFigure 7-15 SPI Transaction Between MCU and SPI version of the device

A valid frame must meet the following conditions:

  • The SCLK pin must be low when the nSCS pin goes low and when the nSCS pin goes high.
  • The nSCS pin should be taken high for at least 500 ns between frames.
  • When the nSCS pin is asserted high, any signals at the SCLK and SDI pins are ignored, and the SDO pin is in the high-impedance state (Hi-Z).
  • Full 16 SCLK cycles must occur.
  • Data is captured on the falling edge of the clock and data is driven on the rising edge of the clock.
  • The most-significant bit (MSB) is shifted in and out first.
  • If the data word sent to SDI pin is less than 16 bits or more than 16 bits, a frame error occurs and the data word is ignored.
  • For a write command, the existing data in the register being written to is shifted out on the SDO pin following the 8-bit command data.