SLVSE57C June   2017  – April 2018 TPS2595

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
      2.      TPS25953x Overvoltage Clamp Response Time
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 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 Switching Characteristics
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Undervoltage Protection (UVP) and Undervoltage Lockout (UVLO)
      2. 8.3.2 Overvoltage Protection
        1. 8.3.2.1 Overvoltage Lockout (OVLO)
        2. 8.3.2.2 Overvoltage Clamp (OVC)
      3. 8.3.3 Inrush Current, Overcurrent and Short Circuit Protection
        1. 8.3.3.1 Slew Rate and Inrush Current Control (dVdt)
        2. 8.3.3.2 Active Current Limiting
        3. 8.3.3.3 Short Circuit Protection
      4. 8.3.4 Overtemperature Protection (OTP)
      5. 8.3.5 Fault Indication (FLT )
      6. 8.3.6 Quick Output Discharge (QOD)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Enable and Fault Pin Functional Mode 1: Single Device, Self-Controlled
      2. 8.4.2 Enable and Fault Pin Functional Mode 2: Single Device, Host-Controlled
      3. 8.4.3 Enable and Fault Pin Functional Mode 2: Multiple Devices, Self-Controlled
  9. 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 Programming the Current-Limit Threshold: RILM Selection
        2. 9.2.2.2 Undervoltage Lockout Set Point
        3. 9.2.2.3 Setting Output Voltage Ramp Time (TdVdT)
          1. 9.2.2.3.1 Case 1: Start-Up Without Load. Only Output Capacitance COUT Draws Current
          2. 9.2.2.3.2 Case 2: Start-Up With Load. Output Capacitance COUT and Load Draw Current
      3. 9.2.3 Support Component Selection: CIN
      4. 9.2.4 Application Curves
      5. 9.2.5 Controlled Power Down (Quick Output Discharge) using TPS2595x5
      6. 9.2.6 Overvoltage Lockout using TPS259573
  10. 10Power Supply Recommendations
    1. 10.1 Transient Protection
    2. 10.2 Output Short-Circuit Measurements
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
      2. 12.1.2 Related Links
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

10.1 Transient Protection

In the case of a short circuit and overload current limit when the device interrupts current flow, the input inductance generates a positive voltage spike on the input, and the output inductance generates a negative voltage spike on the output. The peak amplitude of voltage spikes (transients) is dependent on the value of inductance in series to the input or output of the device. Such transients can exceed the absolute maximum ratings of the device if steps are not taken to address the issue. Typical methods for addressing transients include:

  • Minimize lead length and inductance into and out of the device.
  • Use a large PCB GND plane.
  • Use a Schottky diode across the output to absorb negative spikes.
  • Use a low-value ceramic capacitor CIN = 0.001 μF to 0.1 μF to absorb the energy and dampen the transients.

The approximate value of input capacitance can be estimated with Equation 18:

Equation 18. TPS2595 tps2595x-page-31-equation.gif

where

  • V(IN) is the nominal supply voltage
  • I(LOAD) is the load current
  • L(IN) equals the effective inductance seen looking into the source
  • C(IN) is the capacitance present at the input

Some applications may require the addition of a Transient Voltage Suppressor (TVS) to prevent transients from exceeding the absolute maximum ratings of the device.

The circuit implementation with optional protection components (a ceramic capacitor, TVS and Schottky diode) is shown in Figure 67.

TPS2595 tps2595x-circuit-implementation-with-optional-protection-components-block-diagram.gifFigure 67. Circuit Implementation with Optional Protection Components