SLUSE21B June   2020  – April 2022 UCC27288

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 Switching Characteristics
    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 Start-up and UVLO
      2. 7.3.2 Input Stages
      3. 7.3.3 Level Shifter
      4. 7.3.4 Output Stage
      5. 7.3.5 Negative Voltage Transients
    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 Select Bootstrap and VDD Capacitor
        2. 8.2.2.2 External Bootstrap Diode and Series Resistor
        3. 8.2.2.3 Estimate Driver Power Losses
        4. 8.2.2.4 Selecting External Gate Resistor
        5. 8.2.2.5 Delays and Pulse Width
        6. 8.2.2.6 VDD and Input Filter
        7. 8.2.2.7 Transient Protection
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 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

7.3.1 Start-up and UVLO

Both the high-side and the low-side driver stages include UVLO protection circuitry which monitors the supply voltage (VDD) and the bootstrap capacitor voltage (VHB–HS). The UVLO circuit inhibits each output until sufficient supply voltage is available to turn on the external MOSFETs. The built-in UVLO hysteresis prevents chattering during supply voltage variations. When the supply voltage is applied to the VDD pin of the device, both the outputs are held low until VDD exceeds the UVLO threshold, typically 7.0 V. Any UVLO condition on the bootstrap capacitor (VHB–HS) disables only the high- side output (HO).

Table 7-1 VDD UVLO Logic Operation
Condition (VHB-HS > VHBR HI LI HO LO
VDD-VSS < VDDR during device start-up H L L L
L H L L
H H L L
L L L L
VDD-VSS < VDDR – VDDH after device start-up H L L L
L H L L
H H L L
L L L L
Table 7-2 HB UVLO Logic Operation
Condition (VDD > VDDR HI LI HO LO
VHB-HS < VHBR during device start-up H L L L
L H L H
H H L H
L L L L
VHB-HS < VHBR – VHBH after device start-up H L L L
L H L H
H H L H
L L L L