ZHCSPL6 January 2022 TPS7H4003-SEP
PRODUCTION DATA
- 1 特性
- 2 应用
- 3 说明
- 4 Revision History
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 VIN and Power VIN Pins (VIN and PVIN)
- 7.3.2 Voltage Reference
- 7.3.3 Adjusting the Output Voltage
- 7.3.4 Safe Start-Up Into Prebiased Outputs
- 7.3.5 Error Amplifier
- 7.3.6 Enable and Adjust UVLO
- 7.3.7 Adjustable Switching Frequency and Synchronization (SYNC)
- 7.3.8 Soft-Start (SS/TR)
- 7.3.9 Power Good (PWRGD)
- 7.3.10 Sequencing
- 7.3.11 Output Overvoltage Protection (OVP)
- 7.3.12 Overcurrent Protection
- 7.3.13 Thermal Shutdown
- 7.3.14 Turn-On Behavior
- 7.3.15 Slope Compensation
- 7.3.16 Small Signal Model for Frequency Compensation
- 7.4 Device Functional Modes
-
8 Application and Implementation
- 8.1 Application Information
- 8.2
Typical Application
- 8.2.1 Design Requirements
- 8.2.2
Detailed Design Procedure
- 8.2.2.1 Operating Frequency
- 8.2.2.2 Output Inductor Selection
- 8.2.2.3 Output Capacitor Selection
- 8.2.2.4 Output Schottky Diode
- 8.2.2.5 Input Capacitor Selection
- 8.2.2.6 Soft-Start Capacitor Selection
- 8.2.2.7 Undervoltage Lockout (UVLO) Set Point
- 8.2.2.8 Output Voltage Feedback Resistor Selection
- 8.2.2.9 Compensation Component Selection
- 8.2.3 Parallel Operation
- 8.2.4 Application Curve
- 9 Power Supply Recommendations
- 10Layout
- 11Device and Documentation Support
- 12Mechanical, Packaging, and Orderable Information
8.2.2.9 Compensation Component Selection
There are several industry techniques used to compensate DC-DC regulators. For this design, type 2B compensation is used as shown in the Small Signal Model for Frequency Compensation section.
A good starting rule of thumb is to set the crossover frequency to one-tenth of the switching frequency. This will generally provide good transient response and ensure that the modulator poles do not degrade phase margin.
The compensation components can be calculated using Equation 19 and Equation 21. The values calculated for R3 and C1 are 8.66 kΩ and 12 nF, respectively. Note that frequency compensation is often tuned during testing in order to obtain the best possible performance.
An additional high frequency pole can be used if necessary by adding a capacitor in parallel with the series combination of R3 and C1. The pole frequency is given by Equation 33.
