SNVSBZ7 October   2021 LM5158 , LM51581

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (continued)
  6. Device Comparison Table
  7. Pin Configuration and Functions
  8. Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Typical Characteristics
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Line Undervoltage Lockout (EN/UVLO/SYNC Pin)
      2. 9.3.2  High Voltage VCC Regulator (BIAS, VCC Pin)
      3. 9.3.3  Soft Start (SS Pin)
      4. 9.3.4  Switching Frequency (RT Pin)
      5. 9.3.5  Dual Random Spread Spectrum – DRSS (MODE Pin)
      6. 9.3.6  Clock Synchronization (EN/UVLO/SYNC Pin)
      7. 9.3.7  Current Sense and Slope Compensation
      8. 9.3.8  Current Limit and Minimum On Time
      9. 9.3.9  Feedback and Error Amplifier (FB, COMP Pin)
      10. 9.3.10 Power-Good Indicator (PGOOD Pin)
      11. 9.3.11 Hiccup Mode Overload Protection (MODE Pin)
      12. 9.3.12 Maximum Duty Cycle Limit and Minimum Input Supply Voltage
      13. 9.3.13 Internal MOSFET (SW Pin)
      14. 9.3.14 Overvoltage Protection (OVP)
      15. 9.3.15 Thermal Shutdown (TSD)
    4. 9.4 Device Functional Modes
      1. 9.4.1 Shutdown Mode
      2. 9.4.2 Standby Mode
      3. 9.4.3 Run Mode
        1. 9.4.3.1 Spread Spectrum Enabled
        2. 9.4.3.2 Hiccup Mode Protection Enabled
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Boost Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Custom Design With WEBENCH® Tools
        2. 10.2.2.2 Recommended Components
        3. 10.2.2.3 Inductor Selection (LM)
        4. 10.2.2.4 Output Capacitor (COUT)
        5. 10.2.2.5 Input Capacitor
        6. 10.2.2.6 Diode Selection
      3. 10.2.3 Application Curve
    3. 10.3 System Examples
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Examples
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
      2. 13.1.2 Development Support
        1. 13.1.2.1 Custom Design With WEBENCH® Tools
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Pin Configuration and Functions

GUID-20210118-CA0I-QPFP-TMWF-G1PTPW2QFVJM-low.gifFigure 7-1 RTE Package16-Pin WQFN Top View
Table 7-1 Pin Functions
PINTYPE(1)DESCRIPTION
NO.NAME
1, 16PGNDPPower ground pin. Source connection of the internal N-channel power MOSFET
2VCCPOutput of the internal VCC regulator and supply voltage input of the internal MOSFET driver. Connect a 1-µF ceramic bypass capacitor from this pin to PGND.
3BIASPSupply voltage input to the VCC regulator. Connect a bypass capacitor from this pin to PGND.
4PGOODOPower-good indicator. An open-drain output, which goes low if FB is below the undervoltage threshold (VUVTH). Connect a pullup resistor to the system voltage rail.
5RTISwitching frequency setting pin. The switching frequency is programmed by a single resistor between RT and AGND.
6EN/UVLO/SYNCIEnable pin. The converter shuts down when the pin is less than the enable threshold (VEN).
Undervoltage lockout programming pin. The converter start-up and shutdown levels can be programmed by connecting this pin to the supply voltage through a voltage divider. If using a programmable UVLO, connect the low-side UVLO resistor to AGND. This pin must not be left floating. Connect to the BIAS pin if not used.
External synchronization clock input pin. The internal clock can be synchronized to an external clock by applying a negative pulse signal into the pin.
7AGNDGAnalog ground pin. Connect to the analog ground plane through a wide and short path.
8COMPOOutput of the internal transconductance error amplifier. Connect the loop compensation components between this pin and AGND.
9FBIInverting input of the error amplifier. Connect a voltage divider to set the output voltage in boost, SEPIC, or primary-side regulated flyback topologies. Connect the low-side feedback resistor as close to AGND as possible.
10SSISoft-start time programming pin. An external capacitor and an internal current source set the ramp rate of the internal error amplifier reference during soft start. Connect the ground connection of the capacitor to AGND.
11MODEIMODE = 0 V or connect to AGND during initial power up: Hiccup mode protection is disabled and spread spectrum is disabled.
MODE = 370 mV or connect a 37.4-kΩ resistor between this pin and AGND during initial power up: Hiccup mode protection is enabled and spread spectrum is enabled.
MODE = 620 mV or connect a 62.0-kΩ resistor between this pin and AGND during initial power up: Hiccup mode protection is enabled and spread spectrum is disabled.
MODE > 1 V or connect a 100-kΩ resistor between this pin and AGND during initial power up: Hiccup mode protection is disabled and spread spectrum is enabled.
13, 14SWSwitch pin. Drain connection of the internal N-channel power MOSFET
12, 15NCNo internal electrical contact
EPExposed pad of the package. The exposed pad must be connected to AGND and the large ground copper plane to decrease thermal resistance.
G = Ground, I = Input, O = Output, P = Power