ZHCSGU1C September 2017 – October 2021 LM5150-Q1
PRODUCTION DATA
- 1 特性
- 2 應用
- 3 說明
- 4 Revision History
- 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
- 8.3.1 Enable (EN Pin)
- 8.3.2 High Voltage VCC Regulator (PVCC, AVCC Pin)
- 8.3.3 Power-On Voltage Selection (VSET Pin)
- 8.3.4 Switching Frequency (RT Pin)
- 8.3.5 Clock Synchronization (SYNC Pin in SS Configuration)
- 8.3.6 Current Sense, Slope Compensation, and PWM (CS Pin)
- 8.3.7 Current Limit (CS Pin)
- 8.3.8 Feedback and Error Amplifier (COMP Pin)
- 8.3.9 Automatic Wake-Up and Standby
- 8.3.10 Boost Status Indicator (STATUS Pin)
- 8.3.11 Maximum Duty Cycle Limit, Minimum Input Supply Voltage
- 8.3.12 MOSFET Driver (LO Pin)
- 8.3.13 Thermal Shutdown
- 8.4 Device Functional Modes
-
9 Application and Implementation
- 9.1 Application Information
- 9.2
Typical Application
- 9.2.1 Design Requirements
- 9.2.2
Detailed Design Procedure
- 9.2.2.1 Custom Design With WEBENCH? Tools
- 9.2.2.2 RSET Resistor
- 9.2.2.3 RT Resistor
- 9.2.2.4 Inductor Selection (LM)
- 9.2.2.5 Current Sense (RS)
- 9.2.2.6 Slope Compensation Ramp (RSL)
- 9.2.2.7 Output Capacitor (COUT)
- 9.2.2.8 Loop Compensation Component Selection and Maximum ESR
- 9.2.2.9 PVCC Capacitor, AVCC Capacitor, and AVCC Resistor
- 9.2.2.10 VOUT Filter (CVOUT, RVOUT)
- 9.2.2.11 Input Capacitor
- 9.2.2.12 MOSFET Selection
- 9.2.2.13 Diode Selection
- 9.2.2.14 Efficiency Estimation
- 9.2.3 Application Curves
- 9.3 System Examples
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
8.4.3.1 Start-Stop Configuration (SS Configuration)
Figure 8-7 Typical Start-Stop ApplicationThe LM5150-Q1 runs at fixed switching frequency without any pulse skipping in SS configuration. The device turns on the LO driver every cycle with TON-MIN until entering into standby mode, which helps to prevent EMI spectrum shifts. Because the MOSFET turns on every cycle, the boost converter output can be above the regulation target if the required on-time is less than TON-MIN when the boost supply voltage is close to the VOUT regulation target or the load current is very small. The output voltage will rise above the VOUT regulation target if the one of the inequalities below is true.
In SS configuration, the LM5150-Q1 enters into the standby mode if VOUT is greater than the VOUT standby threshold—which is 24% higher than the VOUT regulation target—or if VIN is greater than the VIN standby threshold.