JAJSEE7B January   2018  – January  2020 TPS92612-Q1

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     代表的なアプリケーションの図
  4. 4 改訂履歴
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Bias
        1. 7.3.1.1 Power-On Reset (POR)
      2. 7.3.2 Constant-Current Driver
      3. 7.3.3 PWM Dimming
      4. 7.3.4 Protection
        1. 7.3.4.1 Short-to-GND Protection
        2. 7.3.4.2 Overtemperature Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Undervoltage Lockout, V(SUPPLY)< V(POR_rising)
      2. 7.4.2 Normal Operation, V(SUPPLY) ≥ 4.5 V
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Single-Channel LED Driver
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Single-Channel LED Driver With Heat Sharing
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11デバイスおよびドキュメントのサポート
    1. 11.1 ドキュメントのサポート
      1. 11.1.1 関連資料
    2. 11.2 ドキュメントの更新通知を受け取る方法
    3. 11.3 コミュニティ・リソース
    4. 11.4 商標
    5. 11.5 静電気放電に関する注意事項
    6. 11.6 Glossary
  12. 12メカニカル、パッケージ、および注文情報

8.2.1.2 Detailed Design Procedure

Current setting by the sense resistor is as described in Equation 1.

Equation 2. TPS92612-Q1 eq-5.gif

LED-string maximum forward voltage = 3 × 2.5 V = 7.5 V.

Total device power consumption at worst case is with 16-V input and LEDs at minimal forward voltage.

Equation 3. TPS92612-Q1 eq06-Pmax_SLDS233.gif

TI recommends to add capacitors C1 and C2 at SUPPLY and OUT. TI recommends C1 of 1 μF and 100 nF close to the SUPPLY pin, and C2 of 10 nF close to the OUT pin. A larger capacitor for C1 or C2 is helpful for EMC and ESD; however, it takes a longer time to charge up the capacitor and could affect PWM dimming performance.