SLLSFB6A May   2020  – April 2021 DRV8705-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Descriptions
  4. 4 Revision History
  5. 5 Pin Configuration
    1.     DRV8705-Q1_RHB Package (VQFN) 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 Timing Requirements
    7. 6.7 Timing Diagrams
    8. 6.8 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 External Components
      2. 7.3.2 Device Interface Variants
        1. 7.3.2.1 Serial Peripheral Interface (SPI)
        2. 7.3.2.2 Hardware (H/W)
      3. 7.3.3 Input PWM Modes
        1. 7.3.3.1 Half-Bridge Control
        2. 7.3.3.2 H-Bridge Control
        3. 7.3.3.3 Split HS and LS Solenoid Control
      4. 7.3.4 Smart Gate Driver
        1. 7.3.4.1 Functional Block Diagram
        2. 7.3.4.2 Slew Rate Control (IDRIVE)
        3. 7.3.4.3 Gate Drive State Machine (TDRIVE)
      5. 7.3.5 Doubler (Single-Stage) Charge Pump
      6. 7.3.6 Low-Side Differential Current Shunt Amplifier
      7. 7.3.7 Pin Diagrams
        1. 7.3.7.1 Logic Level Input Pin (DRVOFF, IN1/EN, IN2/PH, nHIZx, nSLEEP, nSCS, SCLK, SDI)
        2. 7.3.7.2 Logic Level Push Pull Output (SDO)
        3. 7.3.7.3 Logic Level Open Drain Output (nFAULT)
        4. 7.3.7.4 Quad-Level Input (GAIN)
        5. 7.3.7.5 Six-Level Input (IDRIVE, VDS)
      8. 7.3.8 Protection and Diagnostics
        1. 7.3.8.1  Gate Driver Disable and Enable (DRVOFF and EN_DRV)
        2. 7.3.8.2  Fault Reset (CLR_FLT)
        3. 7.3.8.3  DVDD Logic Supply Power on Reset (DVDD_POR)
        4. 7.3.8.4  PVDD Supply Undervoltage Monitor (PVDD_UV)
        5. 7.3.8.5  PVDD Supply Overvoltage Monitor (PVDD_OV)
        6. 7.3.8.6  VCP Charge Pump Undervoltage Lockout (VCP_UV)
        7. 7.3.8.7  MOSFET VDS Overcurrent Protection (VDS_OCP)
        8. 7.3.8.8  Gate Driver Fault (VGS_GDF)
        9. 7.3.8.9  Thermal Warning (OTW)
        10. 7.3.8.10 Thermal Shutdown (OTSD)
        11. 7.3.8.11 Offline Short Circuit and Open Load Detection (OOL and OSC)
        12. 7.3.8.12 Fault Detection and Response Summary Table
    4. 7.4 Device Function Modes
      1. 7.4.1 Inactive or Sleep State
      2. 7.4.2 Standby State
      3. 7.4.3 Operating State
    5. 7.5 Programming
      1. 7.5.1 SPI Interface
      2. 7.5.2 SPI Format
      3. 7.5.3 SPI Interface for Multiple Slaves
        1. 7.5.3.1 SPI Interface for Multiple Slaves in Daisy Chain
    6. 7.6 Register Maps
      1. 7.6.1 STATUS Registers
      2. 7.6.2 CONTROL Registers
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Gate Driver Configuration
          1. 8.2.2.1.1 VCP Load Calculation Example
          2. 8.2.2.1.2 IDRIVE Calculation Example
        2. 8.2.2.2 Current Shunt Amplifier Configuration
        3. 8.2.2.3 Power Dissipation
  9. 9 Power Supply Recommendations
    1. 9.1 Bulk Capacitance
  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. 11.1.2 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RHB|32
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.1 Bulk Capacitance

Having appropriate local bulk capacitance is an important factor in motor drive system design. Having more bulk capacitance is generally beneficial, while the disadvantages are increased cost and physical size.

The amount of local bulk capacitance needed depends on a variety of factors, including:

  • The highest current required by the motor or load
  • The capacitance of the power supply and ability to source current
  • The amount of parasitic inductance between the power supply and motor system
  • The acceptable voltage ripple of the system
  • The motor braking method (if applicable)

The inductance between the power supply and motor drive system limits how the rate current can change from the power supply. If the local bulk capacitance is too small, the system responds to excessive current demands or dumps from the motor with a change in voltage. When adequate bulk capacitance is used, the motor voltage remains stable and high current can be quickly supplied.

The data sheet generally provides a recommended minimum value, but system level testing is required to determine the appropriately sized bulk capacitor.

GUID-98B5B3EF-CA80-4ABE-9340-BB3653819980-low.gifFigure 9-1 System Supply Parasitics Example