SLVS843B December   2008  – May 2018 TPS650250

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Detailed Block Diagram
  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  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Dissipation Ratings
    6. 6.6  Electrical Characteristics
    7. 6.7  Electrical Characteristics VDCDC1
    8. 6.8  Electrical Characteristics VDCDC2
    9. 6.9  Electrical Characteristics VDCDC3
    10. 6.10 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 Step-Down Converters, VDCDC1, VDCDC2 AND VDCDC3
      2. 7.3.2 Power Save Mode Operation
      3. 7.3.3 Soft Start
      4. 7.3.4 100% Duty Cycle Low Dropout Operation
      5. 7.3.5 Low Dropout Voltage Regulators
      6. 7.3.6 Undervoltage Lockout
      7. 7.3.7 PWRFAIL
    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 Typical Configuration For The Samsung Processor S3C6400-533MHz
      2. 8.2.2 Design Requirements
      3. 8.2.3 Detailed Design Procedure
        1. 8.2.3.1 Inductor Selection for the DCDC Converters
        2. 8.2.3.2 Output Capacitor Selection
        3. 8.2.3.3 Input Capacitor Selection
        4. 8.2.3.4 Output Voltage Selection
        5. 8.2.3.5 Voltage Change on VDCDC3
        6. 8.2.3.6 Vdd_alive Output
        7. 8.2.3.7 LDO1 and LDO2
        8. 8.2.3.8 Vcc-Filter
      4. 8.2.4 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 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.4 100% Duty Cycle Low Dropout Operation

The TPS650250x converters offer a low input to output voltage difference while still maintaining operation with the use of the 100% duty cycle mode. In this mode the P-channel switch is constantly turned on. This is particularly useful in battery-powered applications to achieve the longest operation time by taking full advantage of the whole battery voltage range. The minimum input voltage required to maintain DC regulation depends on the load current and output voltage and can be calculated as:

Equation 3. TPS650250 q3_vin_lvs774.gif

where

  • Ioutmax = Maximum load current (note: ripple current in the inductor is zero under these conditions)
  • RDSonmax = Maximum P-channel switch RDSon
  • RL = DC resistance of the inductor
  • Voutmin = Nominal output voltage minus 2% tolerance limit