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

7.1 Overview

The DRV8705-Q1 is an integrated H-bridge smart gate driver for brushed DC motor applications. The device provides two half-bridge gate drivers, capable of driving high-side and low-side N-channel power MOSFETs. The DRV8705-Q1 generates the proper gate drive voltages using an integrated doubler charge pump for the high-side and a linear regulator for the low-side. The gate drivers support up to 62-mA source and 62-mA sink peak gate drive current capability. The device supports a wide operating supply voltage range of 4.9-V to 37-V.

The DRV8705-Q1 is based on a smart gate drive architecture (SGD) to reduce system cost and improve reliability. The SGD architecture optimizes dead time to avoid shoot-through conditions, provides flexibility in decreasing electromagnetic interference (EMI) with MOSFET slew rate control through adjustable gate drive current, and protects against drain to source and gate short circuits conditions with VDS and VGS monitors. A strong pulldown circuit helps prevent dV/dt parasitic gate coupling. The external MOSFET slew control is supported through adjustable output gate drivers. The gate driver peak source current can be configured between 0.5-mA and 62-mA. The gate drivers peak sink current can be configured between 0.5-mA and 62-mA.

The DRV8705-Q1 can operate with either 3.3-V or 5-V external controllers (MCUs). A dedicated DVDD pins allows for external power to the device digital core and the digital outputs to be referenced to the controller I/O voltage. It communicates with the external controller through an SPI bus to manage configuration settings and diagnostic feedback. The device also has an AREF pin which allows for the shunt amplifier reference voltage to be connected to the reference voltage of the external controller ADC. The shunt amplifier outputs are also clamped to the AREF pin voltage to protect the inputs of the controller from excessive voltage spikes.

The DRV8705-Q1 provides an array of diagnostic and protection features to monitor system status before operation and protect against faults during system operation. These include under and overvoltage monitors for the power supply and charge pump, VDS overcurrent and VGS gate fault monitors for the external MOSFETs, offline open load and short circuit detection, and internal thermal warning and shutdown protection. The current shunt amplifier can be utilized to monitor load current of the system.