SLVSAS7D February   2011  – March 2021 DRV8801-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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 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 Power Supervisor
      2. 7.3.2 Bridge Control
        1. 7.3.2.1 MODE 1
        2. 7.3.2.2 MODE 2
      3. 7.3.3 Fast Decay with Synchronous Rectification
      4. 7.3.4 Slow Decay with Synchronous Rectification (Brake Mode)
      5. 7.3.5 Charge Pump
      6. 7.3.6 SENSE
      7. 7.3.7 VPROPI
        1. 7.3.7.1 Connecting VPROPI Output to ADC
      8. 7.3.8 Protection Circuits
        1. 7.3.8.1 VBB Undervoltage Lockout (UVLO)
        2. 7.3.8.2 Overcurrent Protection (OCP)
        3. 7.3.8.3 Overtemperature Warning (OTW)
        4. 7.3.8.4 Overtemperature Shutdown (OTS)
      9. 7.3.9 Thermal Shutdown (TSD)
    4. 7.4 Device Functional Modes
  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 Motor Voltage
        2. 8.2.2.2 Power Dissipation
        3. 8.2.2.3 Thermal Considerations
          1. 8.2.2.3.1 Junction-to-Ambiant Thermal Impedance (ƟJA)
        4. 8.2.2.4 Motor Current Trip Point
        5. 8.2.2.5 Sense Resistor Selection
        6. 8.2.2.6 Drive Current
      3. 8.2.3 Pulse-Width Modulating
        1. 8.2.3.1 Pulse-Width Modulating ENABLE
        2. 8.2.3.2 Pulse-Width Modulating PHASE
      4. 8.2.4 Application Curves
    3. 8.3 Parallel Configuration
      1. 8.3.1 Parallel Connections
      2. 8.3.2 Non – Parallel Connections
      3. 8.3.3 Wiring nFAULT as Wired OR
      4. 8.3.4 Electrical Considerations
        1. 8.3.4.1 Device Spacing
        2. 8.3.4.2 Recirculation Current Handling
        3. 8.3.4.3 Sense Resistor Selection
        4. 8.3.4.4 Maximum System Current
  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. 11.2 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

8.2.2.2 Power Dissipation

The power dissipation of the DRV8801-Q1 is a function of the RMS motor current and the each output’s FET resistance (RDS(ON)).

Equation 3. Power ≈ IRMS2 x (High-Side RDS(ON) + Low-Side RDS(ON))

For this example, the ambient temperature is 35°C, and the junction temperature reaches 65°C. At 65°C, the sum of RDS(ON) is about 1 Ω. With an example motor current of 0.8 A, the dissipated power in the form of heat will be 0.8 A2x 1 Ω = 0.64 W.

The temperature that the DRV8801-Q1 reaches will depend on the thermal resistance to the air and PCB. It is important to solder the device thermal pad to the PCB ground plane, with vias to the top and bottom board layers, to dissipate heat into the PCB and reduce the device temperature. In the example used here, the DRV8801-Q1 had an effective thermal resistance RθJA of 47°C/W, and:

Equation 4. TJ = TA + (PD x RθJA) = 35°C + (0.64 W x 47°C/W) = 65°C