SBVS064O December   2005  – October 2024 TPS74201

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Enable and Shutdown
      2. 6.3.2 Power-Good (VQFN Packages Only)
      3. 6.3.3 Internal Current Limit
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Operation
      2. 6.4.2 Dropout Operation
      3. 6.4.3 Disabled
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Input, Output, and Bias Capacitor Requirements
      2. 7.1.2 Transient Response
      3. 7.1.3 Dropout Voltage
      4. 7.1.4 Output Noise
      5. 7.1.5 Programmable Soft-Start
      6. 7.1.6 Sequencing Requirements
    2. 7.2 Typical Applications
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
      3. 7.4.3 Thermal Protection
      4. 7.4.4 Thermal Considerations
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Evaluation Modules
        2. 8.1.1.2 Spice Models
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
      2. 8.2.2 Device Nomenclature
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

7.1.3 Dropout Voltage

The TPS742 family of devices offers industry-leading dropout performance, making this family well-suited for high-current low VIN/low VOUT applications. The extremely low dropout of the TPS742 allows the device to be used in place of a DC-DC converter and still achieve good efficiency. This efficiency allows the user to rethink the power architecture of applications to achieve the smallest, simplest, and lowest cost solution.

There are two different specifications for dropout voltage with the TPS742 devices. The first specification (illustrated in Figure 7-1) is referred to as VIN Dropout, and is for users who wish to apply an external bias voltage to achieve low dropout. This specification assumes that VBIAS is at least 1.62 V above VOUT, which is the case for VBIAS when powered by a 3.3-V rail with 5% tolerance and with VOUT = 1.5 V. If VBIAS is higher than 3.3 V × 0.95 or VOUT is less than 1.5 V, VIN dropout is less than specified.

TPS74201 Typical Application of the TPS742 Using an Auxiliary Bias RailFigure 7-1 Typical Application of the TPS742 Using an Auxiliary Bias Rail

The second specification (shown in Figure 7-2) is referred to as VBIAS Dropout, and is for users who wish to tie IN and BIAS together. This option allows the device to be used in applications where an auxiliary bias voltage is not available or low dropout is not required. Dropout is limited by BIAS in these applications because VBIAS provides the gate drive to the pass FET and therefore must be 1.4 V above VOUT. Because of this usage, IN and BIAS tied together easily consume huge power. Pay attention not to exceed the power rating of the IC package.

TPS74201 Typical Application of the TPS742 Without an Auxiliary BiasFigure 7-2 Typical Application of the TPS742 Without an Auxiliary Bias