ZHCSIE3B June   2018  – May 2019 LMZM33606

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
    1.     简化电路原理图
  3. 3 说明
    1.     最小解决方案尺寸
    2.     典型效率（自动模式）
  4. 4 修订历史记录
  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 Switching Characteristics
    7. 6.7 Typical Characteristics (VIN = 12 V)
    8. 6.8 Typical Characteristics (VIN = 24 V)
    9. 6.9 Typical Characteristics (VIN = 36 V)
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Adjusting the Output Voltage
      2. 7.3.2  Input Capacitor Selection
      3. 7.3.3  Output Capacitor Selection
      4. 7.3.4  Transient Response
      5. 7.3.5  Feed-Forward Capacitor
      6. 7.3.6  Switching Frequency (RT)
      7. 7.3.7  Synchronization (SYNC/MODE)
      8. 7.3.8  Output Enable (EN)
      9. 7.3.9  Programmable System UVLO (EN)
      10. 7.3.10 Internal LDO and BIAS_SEL
      11. 7.3.11 Power Good (PGOOD) and Power Good Pull-Up (PGOOD_PU)
      12. 7.3.12 Mode Select (Auto or FPWM)
      13. 7.3.13 Soft Start and Voltage Tracking
      14. 7.3.14 Voltage Dropout
      15. 7.3.15 Overcurrent Protection (OCP)
      16. 7.3.16 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Active Mode
      2. 7.4.2 Auto Mode
      3. 7.4.3 FPWM Mode
      4. 7.4.4 Shutdown Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Output Voltage Setpoint
        2. 8.2.2.2 Setting the Switching Frequency
        3. 8.2.2.3 Input Capacitors
        4. 8.2.2.4 Output Capacitor Selection
        5. 8.2.2.5 Feed-Forward Capacitor (CFF)
        6. 8.2.2.6 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Theta JA vs PCB Area
    4. 10.4 Package Specifications
    5. 10.5 EMI
      1. 10.5.1 EMI Plots
  11. 11器件和文档支持
    1. 11.1 器件支持
      1. 11.1.1 第三方产品免责声明
    2. 11.2 接收文档更新通知
    3. 11.3 社区资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 Glossary
  12. 12机械、封装和可订购信息
    1. 12.1 Tape and Reel Information

7.3.1 Adjusting the Output Voltage

A resistor divider connected to the FB pin (pin 15) programs the output voltage of the LMZM33606. The output voltage adjustment range is from 1 V to 20 V. Figure 31 shows the feedback resistor connection for setting the output voltage. The recommended value of RFBB is 10 kΩ. The value for RFBT can be calculated using Equation 1.

Table 1 lists the standard external RFBT values for several standard output voltages along with the recommended switching frequency (FSW) and the frequency setting resistor (RRT) for each of the output voltages listed. (See Voltage Dropout for the allowable output voltage as a function of input voltage.)

space

Equation 1. LMZM33606 Rfbt.gif

where

  • VFB (typical) = 1.006 V
LMZM33606 OrbisonRset.gifFigure 31. Setting the Output Voltage

Table 1. Standard Component Values

VOUT (V) RFBT (kΩ)(1) fSW (kHz) RRT (kΩ)
1.2 1.96 400 100
1.8 7.87 400 100
2.5 15.0 400 100
3.3 22.6 500 78.7 or open
5 40.2 500 78.7 or open
7.5 64.9 500 78.7 or open
12 110 800 47.5
15 140 800 47.5
18 169 1000 38.3
20 191 1000 38.3
(1) RFBB = 10 kΩ.