SNVSCL1 November   2023 LM25185

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Description (continued)
  6. 5 Pin Configuration and Functions
  7. 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
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Power MOSFET Gate Driver
      2. 7.3.2  PSR Flyback Modes of Operation
      3. 7.3.3  High Voltage VCC Regulator
      4. 7.3.4  Setting the Output Voltage
        1. 7.3.4.1 Diode Thermal Compensation
      5. 7.3.5  Control Loop Error Amplifier
      6. 7.3.6  Precision Enable
      7. 7.3.7  Configurable Soft Start
      8. 7.3.8  Minimum On-Time and Off-Time
      9. 7.3.9  Current Sensing and 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
  9. 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 16.4 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 and Current-Sense Resistor (RCS)
          4. 8.2.1.2.4  Flyback Diode – DFLY
          5. 8.2.1.2.5  Leakage Inductance Clamp Circuit – DF, DCLAMP
          6. 8.2.1.2.6  Feedback Resistor – RFB
          7. 8.2.1.2.7  Thermal Compensation Resistor – RTC
          8. 8.2.1.2.8  UVLO Resistors – RUV1, RUV2
          9. 8.2.1.2.9  Soft-Start Capacitor – CSS
          10. 8.2.1.2.10 Compensation Components
        3. 8.2.1.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Examples
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
        1. 9.1.1.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, 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 apply over the full –40°C to 150°C junction temperature range unless otherwise indicated. VIN = 24 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 1.7 µA
IACTIVE VIN active current VEN/UVLO = 2.5 V, VRSET = 1.8 V 425 575 µA
IACTIVE-VCC VIN current with external VCC supply VVCC = 8 V 25 40 µA
BIAS REGULATOR
VVCC-REG VCC regulation voltage 7 V
VVCC-UVLO VCC UVLO rising threshold 4.25 V
VVCC-HYST VCC UVLO hysteresis 0.35 V
IVCC-LIM VCC sourcing current limit 30 mA
ENABLE AND INPUT UVLO
VSD-RISING Standby threshold VEN/UVLO rising 0.8 1.1 V
VSD-FALLING Shutdown threshold VEN/UVLO falling 0.3 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 4.75 5 5.25 µA
FEEDBACK
IRSET RSET current RRSET = 10 kΩ 100 µA
VRSET RSET regulation voltage RRSET = 10 kΩ 0.99 1 1.01 V
VFB-VIN1 FB to VIN voltage IFB = 80 µA –40 mV
VFB-VIN2 FB to VIN voltage IFB = 120 µA 40 mV
ERROR AMPLIFIER
gm EA transconductance 600 uS
ICOMP-SRC VCOMP source current 100 µA
ICOMP-SNK VCOMP sink current -100 µA
SWITCHING FREQUENCY
FSW-MIN Minimum switching frequency 11 kHz
FSW-MAX Maximum switching frequency 350 kHz
tON-MIN Minimum switch on-time 125 ns
DRIVER
VGATE-LOW GATE output low voltage 0.02 V
VGATE-HIGH GATE output high voltage 0.07 V
tGATE-RISE GATE output rise time 30 ns
tGATE-FALL GATE output fall time 15 ns
DIODE THERMAL COMPENSATION
VTC TC voltage ITC = ±10 µA, TJ = 25°C 1 1.05 V
SOFT-START AND BIAS
ISS SS ext capacitor charging current 5 µA
tSS Internal SS time 6 ms
CURRENT LIMIT
VCS-MAX Peak current limit threshold max 95 100 105 mV
VCS-MIN Peak current limit threshold min 18 20 22 mV
tCS-DELAY Peak current limit response time 35 ns
THERMAL SHUTDOWN
TSD Thermal shutdown threshold TJ rising 175 °C
TSD-HYS Thermal shutdown hysteresis 10 °C