JAJSF90F October   2017  – December 2021 TPS2662

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and 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 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Undervoltage Lockout (UVLO)
      2. 9.3.2 Overvoltage Protection (OVP)
      3. 9.3.3 Hot Plug-In and Inrush Current Control
      4. 9.3.4 Reverse Polarity Protection
        1. 9.3.4.1 Input Side Reverse Polarity Protection
        2. 9.3.4.2 Output Side Reverse Polarity Protection
      5. 9.3.5 Overload and Short-Circuit Protection
        1. 9.3.5.1 Overload Protection
        2.       28
        3. 9.3.5.2 Short-Circuit Protection
          1. 9.3.5.2.1 Start-Up With Short-Circuit On Output
      6. 9.3.6 Reverse Current Protection
      7. 9.3.7 FAULT Response
      8. 9.3.8 IN, OUT, RTN, and GND Pins
      9. 9.3.9 Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Low Current Shutdown Control (SHDN)
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Step-by-Step Design Procedure
        2. 10.2.2.2 Programming the Current Limit Threshold R(ILIM) Selection
        3. 10.2.2.3 Undervoltage Lockout and Overvoltage Set Point
        4. 10.2.2.4 Setting Output Voltage Ramp Time—(tdVdT)
          1. 10.2.2.4.1 Case 1: Start-Up Without Load—Only Output Capacitance C(OUT) Draws Current During Start-Up
          2. 10.2.2.4.2 Case 2: Start-Up With Load —Output Capacitance C(OUT) and Load Draws Current During Start-Up
          3. 10.2.2.4.3 Support Component Selections – R FLT and C(IN)
      3. 10.2.3 Application Curves
    3. 10.3 System Examples
      1. 10.3.1 Field Supply Protection in PLC, DCS I/O Modules
      2. 10.3.2 Simple 24-V Power Supply Path Protection
      3. 10.3.3 Power Stealing in Smart Thermostat
    4. 10.4 Do's and Don'ts
  11. 11Power Supply Recommendations
    1. 11.1 Transient Protection
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 サポート・リソース
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

10.2.2.3 Undervoltage Lockout and Overvoltage Set Point

The undervoltage lockout (UVLO) and overvoltage trip point are adjusted using an external voltage divider network of R1, R2 and R3 connected between IN, UVLO, OVP and RTN pins of the device. The values required for setting the undervoltage and overvoltage are calculated by solving Equation 6 and Equation 7.

Equation 6. GUID-ED460F70-6F1A-4567-85AB-F438CEBDA41B-low.gif
Equation 7. GUID-CC0335C5-D065-4491-9312-2AE41D5E85C7-low.gif

For minimizing the input current drawn from the power supply {I(R123) = V(IN) / (R1+R2+R3)}, TI recommends to use higher value resistance for R1, R2 and R3.

However, the leakage current due to external active components connected at resistor string can add error to these calculations. So, the resistor string current, I(R123) must be chosen to be 20 times greater than the leakage current of UVLO and OVP pins.

From the device electrical specifications, V(OVPR) = 1.19 V and V(UVLOR) = 1.19 V. From the design requirements, V(OV) is 30 V and V(UV) is 18 V. To solve the equation, first choose the value of R3 = 30.1 kΩ and use Equation 6 to solve for (R1 + R2) = 728.7 kΩ. Use Equation 7 and value of (R1 + R2) to solve for R2 = 20.05 kΩ and finally R1= 708.6 kΩ.

Choose the closest standard 1% resistor values: R1 = 715 kΩ, R2 = 20 kΩ, and R3 = 30.1 kΩ.