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

8.3.6 Quick Output Discharge (QOD)

Some applications require the output capacitor to be discharged quickly when the eFuse is turned off. This prevents any unpredictable behavior from the downstream devices as the capacitor discharges slowly. The TPS2595x5 device provides a Quick Output Discharge feature that can be enabled by connecting OUT pin to QOD pin. An internal FET provides a fast discharge path for the output capacitor resulting in the OUT voltage falling to 0 V in a short time. The FET initially operates in saturation region and provides a constant current discharge. After the FET enters linear region, it offers a discharge path similar to a resistor.

It is possible to model this as a simple equivalent resistance, which would discharge a given capacitor charged to a given voltage in the same time as the overall discharge circuit. This parameter is specified as the effective QOD resistance RQOD for the device. It takes a time equivalent to 5 time constants (τ = R × C) to discharge a capacitor by 99.3%. For example, with an effective QOD resistance of 19 Ω, the time taken to discharge a 100-µF capacitor from 5 V to 35 mV can be calculated as in Equation 5.

Equation 5. tDischarge = 5 × 19 Ω × 100 µF = 9.5 ms