SLVSEG1A July   2018  – September 2019 TPS56637

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
      2.      Efficiency vs Output Current VOUT = 5 V
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Handling 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  The Adaptive On-Time Control and PWM Operation
      2. 7.3.2  Mode Selection
        1. 7.3.2.1 Eco-mode™ Control Scheme
        2. 7.3.2.2 FCCM Control
      3. 7.3.3  Soft Start and Pre-Biased Soft Start
      4. 7.3.4  Enable and Adjusting Undervoltage Lockout
      5. 7.3.5  Output Overcurrent Limit and Undervoltage Protection
      6. 7.3.6  Overvoltage Protection
      7. 7.3.7  UVLO Protection
      8. 7.3.8  Thermal Shutdown
      9. 7.3.9  Output Voltage Discharge
      10. 7.3.10 Power Good
    4. 7.4 Device Functional Modes
      1. 7.4.1 Standby Operation
      2. 7.4.2 Normal Operation
      3. 7.4.3 Light Load Operation
  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 Output Voltage Resistors Selection
        2. 8.2.2.2 Output Filter Selection
        3. 8.2.2.3 Input Capacitor Selection
        4. 8.2.2.4 Bootstrap Capacitor Selection
      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 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Package Option Addendum
      1. 12.1.1 Packaging Information
      2. 12.1.2 Tape and Reel Information

Package Options

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

7.3.2 Mode Selection

TPS56637 has a MODE pin that can offer 2 different states of operations under light load condition. If MODE pin is short to GND(≤10kΩ), TPS56637 works under Eco-mode™ control scheme. If MODE pin is floating(≥500kΩ), TPS56637 works under FCCM mode.

Figure 15 below shows the typical start-up sequence of the device once the enable signal triggers the EN turn-on threshold. After the voltage of internal VCC crosses the UVLO rising threshold, it takes about 64µs to finish the reading and setting of MODE. After this process, the MODE is latched and will not change until VIN or EN toggles to restart-up this device. Then after a delay of around 650µs the internal soft-start function begins to ramp up the reference voltage to the PWM comparator.

Table 1. MODE Pin Settings

MODE Pin Light Load Operation Mode
Short to GND (≤10kΩ) Eco-mode™
Floating (≥500kΩ) FCCM
TPS56637 powerup-slvseg1.gifFigure 15. Power-Up Sequence