JAJSH37A August   2019  – August 2019 TPS56C230

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      概略回路図
      2.      効率と出力電流との関係、Eco-mode
  4. 4 改訂履歴
  5. 5 概要（続き）
  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 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  PWM Operation and D-CAP3 Control
      2. 8.3.2  Soft Start
      3. 8.3.3  Large Duty Operation
      4. 8.3.4  Power Good
      5. 8.3.5  Overcurrent Protection and Undervoltage Protection
      6. 8.3.6  Overvoltage Protection
      7. 8.3.7  Out-of-Bounds Operation
      8. 8.3.8  UVLO Protection
      9. 8.3.9  Output Voltage Discharge
      10. 8.3.10 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Light Load Operation
      2. 8.4.2 Eco-mode Control
      3. 8.4.3 Force CCM
      4. 8.4.4 Mode Selection
      5. 8.4.5 Standby Operation
  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 Custom Design With WEBENCH® Tools
        2. 9.2.2.2 Output Voltage Set Point
        3. 9.2.2.3 MODE Selection
        4. 9.2.2.4 Inductor Selection
        5. 9.2.2.5 Output Capacitor Selection
        6. 9.2.2.6 Input Capacitor Selection
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 デバイス・サポート
      1. 12.1.1 デベロッパー・ネットワークの製品に関する免責事項
      2. 12.1.2 開発サポート
        1. 12.1.2.1 WEBENCH®ツールによるカスタム設計
    2. 12.2 ドキュメントの更新通知を受け取る方法
    3. 12.3 コミュニティ・リソース
    4. 12.4 商標
    5. 12.5 静電気放電に関する注意事項
    6. 12.6 Glossary
  13. 13メカニカル、パッケージ、および注文情報

8.4.4 Mode Selection

The device reads the voltage on the MODE pin during start-up and latches onto one of the MODE options listed below in Table 1 . The voltage on the MODE pin recommended to be set by connecting this pin to the center tap of a resistor divider connected between VCC and AGND. A guideline for the top resistor (RM_H) and the bottom resistor (RM_L) as 1% resistors is shown in Table 1. It is recommended to choose the resistor to set the voltage at around 5%*VCC for Eco-mode or 15%*VCC for FCCM. It is important that the voltage for the MODE pin is derived from the VCC rail only since internally this voltage is referenced to detect the MODE option, and not to leave the mode pin floating. The MODE pin setting can be reset only by a VIN power cycling or EN toggle.

Table 1. MODE Pin Resistor Settings

Voltage on MODE Recommended Resistor LIGHT LOAD OPERATION
RM_H(kΩ) RM_L (kΩ)
(0~10%)*VCC 330 15 Eco-mode
(10%~20%)*VCC 180 33 FCCM

Figure 17 below shows the typical start-up sequence of the device once the enable signal crosses the EN turn on threshold. After the voltage on VCC crosses the rising UVLO threshold it takes about 500us to read the first mode setting and approximately 100us from there to finish the last mode setting. The output voltage starts ramping after the mode reading is done.

TPS56C230 fbd-12-slvsde4.gifFigure 17. Power-Up Sequence