SLTS278J November   2010  – March 2020 PTH08T250W

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
    1. Table 1. Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 Electrical Characteristics
    3. 7.3 Typical Characteristics (VI = 12 V)
    4. 7.4 Typical Characteristics (VI = 5 V)
  8. 8 Detailed Description
    1. 8.1 Overview: TurboTrans™ Technology
    2. 8.2 Feature Description
      1. 8.2.1 Soft-Start Power-Up
      2. 8.2.2 Differential Output Voltage Remote Sense
      3. 8.2.3 Overcurrent Protection
      4. 8.2.4 Overtemperature Protection (OTP)
  9. 9 Application and Implementation
    1. 9.1 Typical Application
      1. 9.1.1 Detailed Design Procedure
        1. 9.1.1.1  Adjusting the Output Voltage
        2. 9.1.1.2  Capacitor Recommendations for the PTH08T250W Power Module
          1. 9.1.1.2.1 Capacitor Technologies
          2. 9.1.1.2.2 Input Capacitor (Required)
          3. 9.1.1.2.3 Input Capacitor Information
          4. 9.1.1.2.4 Output Capacitor (Required)
          5. 9.1.1.2.5 Output Capacitor Information
          6. 9.1.1.2.6 TurboTrans Output Capacitance
          7. 9.1.1.2.7 Non-TurboTrans Output Capacitance
          8. 9.1.1.2.8 Designing for Fast Load Transients
          9. 9.1.1.2.9 Capacitor Table
        3. 9.1.1.3  TurboTrans™ Technology
        4. 9.1.1.4  TurboTrans™ Selection
          1. 9.1.1.4.1 PTH08T250W Type B Capacitors
            1. 9.1.1.4.1.1 RTT Resistor Selection
          2. 9.1.1.4.2 PTH08T250W Type C Capacitors
            1. 9.1.1.4.2.1 RTT Resistor Selection
        5. 9.1.1.5  Undervoltage Lockout (UVLO)
          1. 9.1.1.5.1 UVLO Adjustment
        6. 9.1.1.6  On/Off Inhibit
        7. 9.1.1.7  Current Sharing
          1. 9.1.1.7.1 Current Sharing and TurboTrans
            1. 9.1.1.7.1.1 Current Sharing Thermal Derating Curves
            2. 9.1.1.7.1.2 Current Sharing Layout
        8. 9.1.1.8  Prebias Startup Capability
        9. 9.1.1.9  SmartSync Technology
        10. 9.1.1.10 Auto-Track™ Function
          1. 9.1.1.10.1 How Auto-Track™ Works
          2. 9.1.1.10.2 Typical Auto-Track Application
          3. 9.1.1.10.3 Notes on Use of Auto-Track™
  10. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  11. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Tape, Reel, and Tray Drawings

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • BCU|22
  • ECT|22
  • ECU|22
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.1.1.2.8 Designing for Fast Load Transients

The transient response of the dc/dc converter has been characterized using a load transient with a di/dt of 2.5 A/µs. The typical voltage deviation for this load transient is given in the Electrical Characteristics table using the minimum required value of output capacitance. As the di/dt of a transient is increased, the response of a converter’s regulation circuit ultimately depends on its output capacitor decoupling network. This is an inherent limitation with any dc/dc converter once the speed of the transient exceeds its bandwidth capability.

If the target application specifies a higher di/dt or lower voltage deviation, the requirement can only be met with additional low ESR ceramic capacitor decoupling. Generally, with load steps greater than 100 A/μs, adding multiple 10 μF ceramic capacitors plus 10 × 1 μF, and numerous high frequency ceramics (≤ 0.1 μF) is all that is required to soften the transient higher frequency edges. The PCB location of these capacitors in relation to the load is critical. DSP, FPGA and ASIC vendors identify types, location and amount of capacitance required for optimum performance. Low impedance buses, unbroken PCB copper planes, and components located as close as possible to the high frequency devices are essential for optimizing transient performance.