JAJSEF3B january   2018  – june 2023 TPS61280D , TPS61280E , TPS61281D

PRODUCTION DATA  

  1.   1
  2. 特長
  3. アプリケーション
  4. 概要
  5. Revision History
  6. 概要 (続き)
  7. Device Comparison Table
  8. Pin Configuration and Functions
  9. Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 I2C Interface Timing Characteristics #GUID-BD85FD7C-B9AF-4F5D-9DFF-CD61365A592A/SLVS5401494
    7. 8.7 I2C Timing Diagrams
    8. 8.8 Typical Characteristics
  10. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Voltage Scaling Management (VSEL)
      2. 9.3.2 Spread Spectrum, PWM Frequency Dithering
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power-Save Mode
      2. 9.4.2 Pass-Through Mode
      3. 9.4.3 Mode Selection
      4. 9.4.4 Current Limit Operation
      5. 9.4.5 Start-Up and Shutdown Mode
      6. 9.4.6 Undervoltage Lockout
      7. 9.4.7 Thermal Shutdown
      8. 9.4.8 Fault State and Power-Good
    5. 9.5 Programming
      1. 9.5.1 Serial Interface Description (TPS61280D/E)
      2. 9.5.2 Standard-, Fast-, Fast-Mode Plus Protocol
      3. 9.5.3 HS-Mode Protocol
      4. 9.5.4 TPS6128xD/E I2C Update Sequence
    6. 9.6 Register Maps
      1. 9.6.1  Slave Address Byte
      2. 9.6.2  Register Address Byte
      3. 9.6.3  I2C Registers, E2PROM, Write Protect
      4. 9.6.4  E2PROM Configuration Parameters
      5. 9.6.5  CONFIG Register [reset = 0x01]
      6. 9.6.6  VOUTFLOORSET Register [reset = 0x02]
      7. 9.6.7  VOUTROOFSET Register [reset = 0x03]
      8. 9.6.8  ILIMSET Register [reset = 0x04]
      9. 9.6.9  Status Register [reset = 0x05]
      10. 9.6.10 E2PROMCTRL Register [reset = 0xFF]
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 TPS61281D with 2.5V-4.35 VIN, 1500 mA Output Current (TPS61280D with default I2C Configuration)
        1. 10.2.1.1 Design Requirement
        2. 10.2.1.2 Detailed Design Parameters
          1. 10.2.1.2.1 Inductor Selection
          2. 10.2.1.2.2 Output Capacitor
          3. 10.2.1.2.3 Input Capacitor
          4. 10.2.1.2.4 Checking Loop Stability
        3. 10.2.1.3 Application Performance Curves
      2. 10.2.2 TPS61282D with 2.5V-4.35 VIN, 2000 mA Output Current (TPS61280D with I2C Programmable)
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedures
        3. 10.2.2.3 Application Performance Curves
  12. 11Power Supply Recommendations
  13. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Information
  14. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 サード・パーティ製品に関する免責事項
    2. 13.2 ドキュメントの更新通知を受け取る方法
    3. 13.3 サポート・リソース
    4. 13.4 Trademarks
    5. 13.5 静電気放電に関する注意事項
    6. 13.6 用語集
  15. 14Mechanical, Packaging, and Orderable Information
    1. 14.1 Package Summary

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
Inductor Selection

A boost converter normally requires two main passive components for storing energy during the conversion, an inductor and an output capacitor are required. It is advisable to select an inductor with a saturation current rating higher than the possible peak current flowing through the power switches.

The inductor peak current varies as a function of the load, the input and output voltages and can be estimated using Equation 8.

Equation 8. GUID-2301FC16-F0F9-47CE-9B58-52B68B785735-low.gif

Selecting an inductor with insufficient saturation performance can lead to excessive peak current in the converter. This could eventually harm the device and reduce it's reliability.

When selecting the inductor, as well as the inductance, parameters of importance are: maximum current rating, series resistance, and operating temperature. The inductor DC current rating should be greater than the maximum input average current, refer to Equation 9 and the Section 9.4.4 section for more details.

Equation 9. GUID-7B6F9011-0481-458A-9262-58A60CDBC217-low.gif

The TPS6128xD series of step-up converters have been optimized to operate with a effective inductance in the range of 200 nH to 800 nH. Larger or smaller inductor values can be used to optimize the performance of the device for specific operating conditions. For more details, see the Section 10.2.1.2.4 section.

In high-frequency converter applications, the efficiency is essentially affected by the inductor AC resistance (that is, quality factor) and to a smaller extent by the inductor DCR value. To achieve high efficiency operation, care should be taken in selecting inductors featuring a quality factor above 25 at the switching frequency. Increasing the inductor value produces lower RMS currents, but degrades transient response. For a given physical inductor size, increased inductance usually results in an inductor with lower saturation current.

The total losses of the coil consist of both the losses in the DC resistance, R(DC) , and the following frequency-dependent components:

  • The losses in the core material (magnetic hysteresis loss, especially at high switching frequencies)
  • Additional losses in the conductor from the skin effect (current displacement at high frequencies)
  • Magnetic field losses of the neighboring windings (proximity effect)
  • Radiation losses

For good efficiency, the inductor DC resistance should be less than 30 mΩ. The following inductor series from different suppliers have been used with the TPS6128xD converters.

Table 10-2 List of Inductors
SERIESDIMENSIONS (in mm)DC INPUT CURRENT LIMIT SETTING
DFE252010C2.5 x 2.0 x 1.0 max. height≤3000 mA
DFE252012C2.5 x 2.0 x 1.2 max. height≤3500 mA
DFR252010C2.5 x 2.0 x 1.0 max. height≤3000 mA
DFE252012C2.5 x 2.0 x 1.2 max. height≤3500 mA
DFE252012P2.5 x 2.0 x 1.2 max. height≤3500 mA
DFE201610C2.0 x 1.6 x 1.0 max. height≤2000 mA
DFE201612C2.0 x 1.6 x 1.2 max. height≤3000 mA
DFE201612P2.0 x 1.6 x 1.2 max. height≤3000 mA