SLUSE80C September   2021  – December 2022 UCC14240-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  Power Ratings
    6. 6.6  Insulation Specifications
    7. 6.7  Safety-Related Certifications
    8. 6.8  Electrical Characteristics
    9. 6.9  Safety Limiting Values
    10. 6.10 Insulation Characteristics
    11. 6.11 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 Stage Operation
        1. 7.3.1.1 VDD-VEE Voltage Regulation
        2. 7.3.1.2 COM-VEE Voltage Regulation
        3. 7.3.1.3 Power Handling Capability
      2. 7.3.2 Output Voltage Soft Start
      3. 7.3.3 ENA and PG
      4. 7.3.4 Protection Functions
        1. 7.3.4.1 Input Undervoltage Lockout
        2. 7.3.4.2 Input Overvoltage Lockout
        3. 7.3.4.3 Output Overvoltage Protection
        4. 7.3.4.4 Overpower Protection
          1. 7.3.4.4.1 Output Undervoltage Protection
        5. 7.3.4.5 Overtemperature Protection
    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 Capacitor Selection
        2. 8.2.2.2 RLIM Resistor Selection
      3. 8.2.3 Application Curves
    3. 8.3 System Examples
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  9. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  10. 10Mechanical, Packaging, and Orderable Information

7.4 Device Functional Modes

Depending on the input and output conditions, ENA pin voltage, as well as the device temperature, the UCC14240-Q1 operates in one of the below operation modes.

  1. Disable mode. In this mode, the module is off, but waiting for ENA pin becoming high to start operate.
  2. Soft-start mode. In this mode, the module starts to deliver power to the secondary side. The primary-side operation duty cycle and secondary-side references are raised gradually to reduce the stress to the module.
  3. Normal operation mode. In this mode, the module operates normally, delivers power to the secondary side.
  4. Protection mode, auto-recovery. In this mode, the module is off, due to the input UVLO or OVLO protection. After the input voltage fault is cleared, depending on the ENA pin voltage condition, it either becomes disabled mode if the ENA pin voltage is low, or it goes through soft-start mode to the normal operation mode.
  5. Protection mode, latched-off. In this mode, the module is off, due to other protections. The module remains off even the fault causing the protection is cleared. Recycling VVIN operation must ensure the input voltage goes below the analog UVLO falling threshold (VVIN_ ANALOG_UVLOP_FALLING ) first to reset the latch-off state, or the ENA pin is toggled Low (OFF) then High (ON).

Table 7-1 lists the supply functional modes for this device. The ENA pin has an internal weak pull-down resistance to ground, but TI does not recommend leaving this pin open.

Table 7-1 Device Functional Modes

INPUT

OUTPUTS

Operation Mode
VVINENAFAULTV(VDD – VEE)
Isolated Output1		V(COM – VEE)
Isolated Output2		PG Open Drain
VVIN < VVIN_UVLOP_RISINGXXOFFOFFHighProtection mode, auto-recovery
VVIN_UVLOP_RISING < VVIN < VVIN_OVLO_RISINGLOWXOFFOFFHighDisable mode
VVIN_UVLOP_RISING < VVIN < VVIN_OVLO_RISINGHIGHNO FAULTRegulating at SetpointRegulating at SetpointLowNormal operation
VVIN_UVLOP_RISING < VVIN < VVIN_OVLO_RISINGHIGHYES FAULTOFFOFFHighProtection mode, latched-off
VVIN > VVIN_OVLO_RISINGXXOFFOFFHighProtection mode, auto-recovery