SNVSB96 July   2019 LM3424-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
    1.     Typical Boost Application Circuit
  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  Current Regulators
      2. 7.3.2  Peak Current Mode Control
      3. 7.3.3  Average LED Current
      4. 7.3.4  Thermal Foldback and Analog Dimming
      5. 7.3.5  Current Sense and Current Limit
      6. 7.3.6  Slope Compensation
      7. 7.3.7  Control Loop Compensation
      8. 7.3.8  Start-Up Regulator and Soft-Start
      9. 7.3.9  Overvoltage Lockout (OVLO)
      10. 7.3.10 Input Undervoltage Lockout (UVLO)
        1. 7.3.10.1 UVLO Only
        2. 7.3.10.2 PWM Dimming and UVLO
      11. 7.3.11 PWM Dimming
      12. 7.3.12 Thermal Shutdown
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Inductor
      2. 8.1.2 LED Dynamic Resistance
      3. 8.1.3 Output Capacitor
      4. 8.1.4 Input Capacitors
      5. 8.1.5 Main MOSFET and Dimming MOSFET
      6. 8.1.6 Re-Circulating Diode
      7. 8.1.7 Switching Frequency
    2. 8.2 Typical Applications
      1. 8.2.1 Basic Topology Schematics
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Operating Point
          2. 8.2.1.2.2  Switching Frequency
          3. 8.2.1.2.3  Average LED Current
          4. 8.2.1.2.4  Thermal Foldback
          5. 8.2.1.2.5  Inductor Ripple Current
          6. 8.2.1.2.6  LED Ripple Current
          7. 8.2.1.2.7  Peak Current Limit
          8. 8.2.1.2.8  Slope Compensation
          9. 8.2.1.2.9  Loop Compensation
          10. 8.2.1.2.10 Input Capacitance
          11. 8.2.1.2.11 NFET
          12. 8.2.1.2.12 Diode
          13. 8.2.1.2.13 Output OVLO
          14. 8.2.1.2.14 Input UVLO
          15. 8.2.1.2.15 Soft-Start
          16. 8.2.1.2.16 PWM Dimming Method
          17. 8.2.1.2.17 Analog Dimming Method
      2. 8.2.2 Buck-Boost Application
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1  Operating Point
          2. 8.2.2.2.2  Switching Frequency
          3. 8.2.2.2.3  Average LED Current
          4. 8.2.2.2.4  Thermal Foldback
          5. 8.2.2.2.5  Inductor Ripple Current
          6. 8.2.2.2.6  Output Capacitance
          7. 8.2.2.2.7  Peak Current Limit
          8. 8.2.2.2.8  Slope Compensation
          9. 8.2.2.2.9  Loop Compensation
          10. 8.2.2.2.10 Input Capacitance
          11. 8.2.2.2.11 NFET
          12. 8.2.2.2.12 Diode
          13. 8.2.2.2.13 Input UVLO
          14. 8.2.2.2.14 Output OVLO
          15. 8.2.2.2.15 Soft-Start
        3. 8.2.2.3 Application Curve
      3. 8.2.3 Boost Application
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
      4. 8.2.4 Buck-Boost Application
        1. 8.2.4.1 Design Requirements
        2. 8.2.4.2 Detailed Design Procedures
      5. 8.2.5 Boost Application
        1. 8.2.5.1 Design Requirements
        2. 8.2.5.2 Detailed Design Procedure
      6. 8.2.6 Buck-Boost Application
        1. 8.2.6.1 Design Requirements
        2. 8.2.6.2 Detailed Design Procedure
      7. 8.2.7 Buck Application
        1. 8.2.7.1 Design Requirements
        2. 8.2.7.2 Detailed Design Procedure
      8. 8.2.8 Buck-Boost Application
        1. 8.2.8.1 Design Requirements
        2. 8.2.8.2 Detailed Design Procedure
      9. 8.2.9 SEPIC Application
        1. 8.2.9.1 Design Requirements
        2. 8.2.9.2 Detailed Design Procedure
  9. 9 Power Supply Recommendations
    1. 9.1 Input Supply Current Limit
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.2.7.2 Detailed Design Procedure

Table 6. Bill of Materials

QTY PART ID PART VALUE MANUFACTURER PART NUMBER
1 LM3424 Boost controller TI LM3424MH
1 CBYP 2.2 µF X7R 10% 16V MURATA GRM21BR71C225KA12L
2 CCMP, CDIM 0.1 µF X7R 10% 25V MURATA GRM21BR71E104KA01L
0 CFS DNP
1 CNTC 0.33 µF X7R 10% 25V MURATA GRM21BR71E334KA01L
4 CIN 4.7 µF X7R 10% 100V TDK C5750X7R2A475K
0 COUT DNP
1 COV 47 pF COG/NPO 5% 50V AVX 08055A470JAT2A
1 CREF, CSS 1 µF X7R 10% 25V MURATA GRM21BR71E105KA01L
1 D1 Schottky 100V 12A VISHAY 12CWQ10FNPBF
1 D2 Zener 10V 500mA ON-SEMI BZX84C10LT1G
1 L1 22 µH 20% 7.3A COILCRAFT MSS1278-223MLB
1 Q1 NMOS 60V 8A VISHAY SI4436DY
1 Q2 PMOS 30V 6.2A VISHAY SI3483DV
1 Q3 NMOS 60V 115mA ON-SEMI 2N7002ET1G
1 Q4 PNP 150V 600 mA FAIRCHILD MMBT5401
3 RBIAS, RREF1, RREF2 49.9 kΩ 1% VISHAY CRCW080549K9FKEA
1 RCSH 12.4 kΩ 1% VISHAY CRCW080512K4FKEA
1 RFS 0Ω 1% VISHAY CRCW08050000OZEA
1 RGAIN, RT 10.0 kΩ 1% VISHAY CRCW080510K0FKEA
2 RHSP, RHSN 1.0 kΩ 1% VISHAY CRCW08051K00FKEA
1 RLIM 0.04Ω 1% 1W VISHAY WSL2512R0400FEA
1 ROV1 21.5 kΩ 1% VISHAY CRCW080521K5FKEA
1 ROV2 499 kΩ 1% VISHAY CRCW0805499KFKEA
1 RPOT 50 kΩ potentiometer BOURNS 3352P-1-503
2 RPU, RUV2 100 kΩ 1% VISHAY CRCW0805100KFKEA
1 RSLP 36.5 kΩ 1% VISHAY CRCW080536K5FKEA
1 RSNS 0.08Ω 1% 1W VISHAY WSL2512R0800FEA
1 RUV1 11.5 kΩ 1% VISHAY CRCW080511K5FKEA