SLVSFM1 March   2021 TPS62902

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Mode Selection and Device Configuration MODE/S-CONF
      2. 7.3.2 Adjustable VO Operation (External Voltage Divider)
      3. 7.3.3 Setable VO Operation (VSET and Internal Voltage Divider)
      4. 7.3.4 Soft Start / Tracking (SS/TR)
      5. 7.3.5 Smart Enable with Precise Threshold
      6. 7.3.6 Power Good (PG)
      7. 7.3.7 Undervoltage Lockout (UVLO)
      8. 7.3.8 Current Limit And Short Circuit Protection
      9. 7.3.9 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Pulse Width Modulation (PWM) Operation
      2. 7.4.2 AEE (Automatic Efficiency Enhancement)
      3. 7.4.3 Power Save Mode Operation (Auto PFM/PWM)
      4. 7.4.4 100% Duty-Cycle Operation
      5. 7.4.5 Output Discharge Function
      6. 7.4.6 Starting into a Pre-Biased Load
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application with Adjustable Output Voltage
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Programming the Output Voltage
        3. 8.2.2.3 External Component Selection
        4. 8.2.2.4 Inductor Selection
        5. 8.2.2.5 Capacitor Selection
          1. 8.2.2.5.1 Output Capacitor
          2. 8.2.2.5.2 Input Capacitor
          3. 8.2.2.5.3 Soft-Start Capacitor
        6. 8.2.2.6 Tracking Function
        7. 8.2.2.7 Output Filter and Loop Stability
      3. 8.2.3 Application Curves
      4. 8.2.4 Typical Application with Setable VO using VSET
        1. 8.2.4.1 Design Requirements
        2. 8.2.4.2 Detailed Design Procedure
        3. 8.2.4.3 Application Curves
    3. 8.3 System Examples
      1. 8.3.1 LED Power Supply
      2. 8.3.2 Powering Multiple Loads
      3. 8.3.3 Voltage Tracking
      4. 8.3.4 Precise Soft-Start Timing
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
      1. 10.2.1 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 Custom Design With WEBENCH® Tools
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
  • RPJ|9
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Precise Soft-Start Timing

The SS/TR pin of the TPS6290x can be used for tracking as well as for setting the Soft-Start time. The TPS6290x has one GND terminal which is used for the power ground as well as for the analog ground connection. While starting the device with a load current above approximately 1 A, the noise on the GND connection can lead to a Soft-Start time shorter than calculated. There are two external work arounds as given below.

Adding a 10.?? kΩ resistor filters the noise on the GND connection and keeps the Soft-Start time at the value calculated.

Figure 8-85 does not require an external component. It provides a connection to the internal analog ground by using the FB2 pin and its internal NMOS to that node. The internal NMOS needs to be turned ON by setting VSEL = high.

GUID-7DC50EFA-3107-4790-9945-C3F0F1231950-low.gif Figure 8-84 Adding a Series Resistor to CSS
GUID-7DC50EFA-3107-4790-9945-C3F0F1231950-low.gif Figure 8-85 Connecting CSS to the Internal Analog Ground by using FB2