ZHCSCO9B June 2014 – January 2018 LM46001
PRODUCTION DATA.
- 1 特性
- 2 應(yīng)用
- 3 說明
- 4 修訂歷史記錄
- 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 Fixed-Frequency, Peak-Current Mode Controlled Step-Down Regulator
- 7.3.2 Light Load Operation
- 7.3.3 Adjustable Output Voltage
- 7.3.4 Enable (ENABLE)
- 7.3.5 VCC, UVLO, and BIAS
- 7.3.6 Soft-Start and Voltage Tracking (SS/TRK)
- 7.3.7 Switching Frequency (RT) and Synchronization (SYNC)
- 7.3.8 Minimum ON-Time, Minimum OFF-Time and Frequency Foldback at Dropout Conditions
- 7.3.9 Internal Compensation and CFF
- 7.3.10 Bootstrap Voltage (CBOOT)
- 7.3.11 Power Good (PGOOD)
- 7.3.12 Overcurrent and Short-Circuit Protection
- 7.3.13 Thermal Shutdown
- 7.4 Device Functional Modes
-
8 Applications and Implementation
- 8.1 Application Information
- 8.2
Typical Applications
- 8.2.1 Design Requirements
- 8.2.2
Detailed Design Procedure
- 8.2.2.1 Custom Design With WEBENCH? Tools
- 8.2.2.2 Output Voltage Setpoint
- 8.2.2.3 Switching Frequency
- 8.2.2.4 Input Capacitors
- 8.2.2.5 Inductor Selection
- 8.2.2.6 Output Capacitor Selection
- 8.2.2.7 Feed-Forward Capacitor
- 8.2.2.8 Bootstrap Capacitors
- 8.2.2.9 VCC Capacitor
- 8.2.2.10 BIAS Capacitors
- 8.2.2.11 Soft-Start Capacitors
- 8.2.2.12 Undervoltage Lockout Setpoint
- 8.2.2.13 PGOOD
- 8.2.3 Application Curves
- 9 Power Supply Recommendations
- 10Layout
- 11器件和文檔支持
- 12機(jī)械、封裝和可訂購(gòu)信息
封裝選項(xiàng)
機(jī)械數(shù)據(jù) (封裝 | 引腳)
- PWP|16
散熱焊盤機(jī)械數(shù)據(jù) (封裝 | 引腳)
- PWP|16
訂購(gòu)信息
8.2.2.2 Output Voltage Setpoint
The output voltage of the LM46001 device is externally adjustable using a resistor divider network. The divider network is comprised of top feedback resistor RFBT and bottom feedback resistor RFBB. The following equation is used to determine the output voltage of the converter:
Choose the value of the RFBT to be 1 MΩ to minimize quiescent current to improve light load efficiency in this application. With the desired output voltage set to be 3.3 V and the VFB = 1.016 V, the RFBB value can then be calculated using Equation 11. The formula yields a value of 444.83 kΩ. Choose the closest available value of 442 kΩ for the RFBB. See Adjustable Output Voltage for more details.