ZHCSJ36 November 2018 TPS543C20A
PRODUCTION DATA.
- 1 特性
- 2 應用
- 3 說明
- 4 修訂歷史記錄
- 5 Device Comparison Table
- 6 Pin Configuration and Functions
- 7 Specifications
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3 Feature Description
- 8.4
Device Functional Modes
- 8.4.1 Soft-Start Operation
- 8.4.2 Input and VDD Undervoltage Lockout (UVLO) Protection
- 8.4.3 Power Good and Enable
- 8.4.4 Voltage Reference
- 8.4.5 Prebiased Output Start-up
- 8.4.6 Internal Ramp Generator
- 8.4.7 Switching Frequency
- 8.4.8 Clock Sync Point Selection
- 8.4.9 Synchronization and Stackable Configuration
- 8.4.10 Dual-Phase Stackable Configurations
- 8.4.11 Operation Mode
- 8.4.12 API/Body Brake
- 8.4.13 Sense and Overcurrent Protection
- 8.4.14 Output Overvoltage and Undervoltage Protection
- 8.4.15 Overtemperature Protection
- 8.4.16 RSP/RSN Remote Sense Function
- 8.4.17 Current Sharing
- 8.4.18 Loss of Synchronization
-
9 Application and Implementation
- 9.1 Application Information
- 9.2
Typical Application: TPS543C20A Stand-alone Device
- 9.2.1 Design Requirements
- 9.2.2 Detailed Design Procedure
- 9.2.3 Application Curves
- 9.3 System Example
- 10Power Supply Recommendations
- 11Layout
- 12器件和文檔支持
- 13機械、封裝和可訂購信息
8.4.12 API/Body Brake
is a true fixed frequency converter. The major limitation for any fixed frequency converter is that during transient load step up, the converter needs to wait for the next clock cycle to response to the load change, depending on loop bandwidth design and the timing of load transient, this delay time could cause additional output voltage drop. implements a special circuitry to improve transient performance. During load step up, the converter senses both the speed and the amplitude of the output voltage change, if the output voltage change is fast and big enough, the converter will issue an additional PWM pulse before the next available clock cycle to stop output voltage from further dropping, thus reducing the undershoot voltage.
During load step-down, implements a body-brake function, that turns off both high-side and lowside FET, and allows power to dissipate through the low-side body diode, reducing overshoot. This approach is very effective while having some impact on efficiency during transient. See Figure 21 and Figure 22.
Figure 21. Undershoot Comparison with API ON/OFF 
Figure 22. Overshoot Comparison with Body Brake ON/OFF