SLVSD86B december   2015  – may 2023 TPS65265

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Adjusting the Output Voltage
      2. 8.3.2  Mix PGOOD, PG_DLY Functions
        1. 8.3.2.1 Programmable PGOOD DELAY
        2. 8.3.2.2 Relay Control
      3. 8.3.3  Enable and Adjusting UVLO
      4. 8.3.4  Soft-Start Time
      5. 8.3.5  Power-Up Sequencing
        1. 8.3.5.1 External Power Sequencing
        2. 8.3.5.2 Automatic Power Sequencing
      6. 8.3.6  V7V Low Dropout Regulator and Bootstrap
      7. 8.3.7  Out of Phase Operation
      8. 8.3.8  Output Overvoltage Protection (OVP)
      9. 8.3.9  PSM
      10. 8.3.10 Slope Compensation
      11. 8.3.11 Overcurrent Protection
        1. 8.3.11.1 High-Side MOSFET Overcurrent Protection
        2. 8.3.11.2 Low-Side MOSFET Overcurrent Protection
      12. 8.3.12 Adjustable Switching Frequency
      13. 8.3.13 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operation With VIN < 4 V (Minimum VIN)
      2. 8.4.2 Operation With EN Control
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Output Inductor Selection
        2. 9.2.2.2 Output Capacitor Selection
        3. 9.2.2.3 Input Capacitor Selection
        4. 9.2.2.4 Loop Compensation
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.5.1 External Power Sequencing

The TPS65265 has dedicated enable pin and soft-start pin for each converter. The converter enable pins are biased by a current source that allows for easy sequencing by the addition of an external capacitor. Disabling the converter with an active pulldown transistor on the ENx pin allows for a predictable powerdown timing operation. The Figure 8-5 shows the timing diagram of a typical buck power-up sequence with connecting a capacitor at ENx pin.

A typical 1.4-µA current is charging ENx pin from input supply. When ENx pin voltage rise to typical 0.4 V, the internal V7V LDO turns on. A 2.9-µA pullup current is sourcing ENx. After ENx pin voltage reaches to ENx enabling threshold, 3.1-µA hysteresis current sources to the pin to improve noise sensitivity. After soft start time of 2.4 ms (typical), PGOOD monitor is enabled. If all output voltages are in the regulation and after PGOOD delay time, PGOOD is asserted.

GUID-2DCD3A83-F9FA-4140-BA79-5E3BBBF8DCB2-low.gifFigure 8-5 Startup Power Sequence