SNVSBL7A March   2020  – August 2020 LM25184

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  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 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Integrated Power MOSFET
      2. 7.3.2  PSR Flyback Modes of Operation
      3. 7.3.3  Setting the Output Voltage
        1. 7.3.3.1 Diode Thermal Compensation
      4. 7.3.4  Control Loop Error Amplifier
      5. 7.3.5  Precision Enable
      6. 7.3.6  Configurable Soft Start
      7. 7.3.7  External Bias Supply
      8. 7.3.8  Minimum On-Time and Off-Time
      9. 7.3.9  Overcurrent Protection
      10. 7.3.10 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1: Wide VIN, Low IQ PSR Flyback Converter Rated at 12 V, 1 A
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 8.2.1.2.2  Custom Design With Excel Quickstart Tool
          3. 8.2.1.2.3  Flyback Transformer – T1
          4. 8.2.1.2.4  Flyback Diode – DFLY
          5. 8.2.1.2.5  Leakgae Inductance Clamp Circuit – DF, DCLAMP
          6. 8.2.1.2.6  Output Capacitor – COUT
          7. 8.2.1.2.7  Input Capacitor – CIN
          8. 8.2.1.2.8  Feedback Resistor – RFB
          9. 8.2.1.2.9  Thermal Compensation Resistor – RTC
          10. 8.2.1.2.10 UVLO Resistors – RUV1, RUV2
          11. 8.2.1.2.11 Soft-Start Capacitor – CSS
      2. 8.2.2 Application Curves
      3. 8.2.3 Design 2: PSR Flyback Converter With Dual Outputs of 15 V and –8 V at 0.5 A
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
          1. 8.2.3.2.1 Flyback Transformer – T1
          2. 8.2.3.2.2 Flyback Diodes – DFLY1 and DFLY2
          3. 8.2.3.2.3 Input Capacitor – CIN
          4. 8.2.3.2.4 Output Capacitors – COUT1, COUT2
          5. 8.2.3.2.5 Feedback Resistor – RFB
          6. 8.2.3.2.6 Thermal Compensation Resistor – RTC
          7. 8.2.3.2.7 Output Voltage Clamp Zeners – DOUT1 and DOUT2
        3. 8.2.3.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
        1. 11.1.2.1 Custom Design With WEBENCH® Tools
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

6.5 Electrical Characteristics

Typical values correspond to TJ = 25°C. Minimum and maximum limits aaply over the full –40°C to 150°C junction temperature range unless otherwise indicated. VIN = 12 V and VEN/UVLO = 2 V unless otherwise stated.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY CURRENT
ISHUTDOWN VIN shutdown current VEN/UVLO = 0 V 1.8 µA
IACTIVE VIN active current VEN/UVLO = 2.5 V, VRSET = 1.8 V 260 375 µA
IACTIVE-BIAS VIN current with BIAS connected VSS/BIAS = 5 V 25 50 µA
ENABLE AND INPUT UVLO
VSD-FALLING Shutdown threshold VEN/UVLO falling 0.3 V
VSD-RISING Standby threshold VEN/UVLO rising 0.8 1 V
VUV-RISING Enable threshold VEN/UVLO rising 1.45 1.5 1.53 V
VUV-HYST Enable voltage hysteresis VEN/UVLO falling 0.04 0.05 V
IUV-HYST Enable current hysteresis VEN/UVLO = 1.6 V 4.2 5 5.5 µA
FEEDBACK
IRSET RSET current RRSET = 12.1 kΩ 100 µA
VRSET RSET regulation voltage RRSET = 12.1 kΩ 1.194 1.21 1.22 V
VFB-VIN1 FB to VIN voltage IFB = 80 µA –50 mV
VFB-VIN2 FB to VIN voltage IFB = 120 µA 50 mV
SWITCHING FREQUENCY
FSW-MIN Minimum switching frequency 12 kHz
FSW-MAX Maximum switching frequency 350 kHz
tON-MIN Minimum switch on-time 140 ns
DIODE THERMAL COMPENSATION
VTC TC voltage ITC = ±10 µA, TJ = 25°C 1.2 1.27 V
POWER SWITCHES
RDS(on) MOSFET on-state resistance ISW = 100 mA, TJ = 25°C 0.11 0.135 Ω
SOFT-START AND BIAS
ISS SS ext capacitor charging current 5 µA
tSS Internal SS time 6 ms
VBIAS-UVLO-RISE BIAS enable voltage VSS/BIAS rising 4.25 4.45 V
VBIAS-UVLO-HYST BIAS UVLO hysteresis VSS/BIAS falling 130 mV
CURRENT LIMIT
ISW-PEAK Peak current limit threshold 3.6 4.1 4.4 A
THERMAL SHUTDOWN
TSD Thermal shutdown threshold TJ rising 175 °C
TSD-HYS Thermal shutdown hysteresis 10 °C