SNVS603D August   2009  – July 2019 LM3424

PRODUCTION DATA.  

  1. Features
  2. Applications
    1.     Typical Boost Application Circuit
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  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. 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. 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. 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

Detailed Design Procedure

Table 5. Bill of Materials

QTY PART ID PART VALUE MANUFACTURER PART NUMBER
1 LM3424 Boost controller TI LM3424MH
1 CB 100 pF COG/NPO 5% 50V MURATA GRM2165C1H101JA01D
1 CBYP 2.2 µF X7R 10% 16V MURATA GRM21BR71C225KA12L
2 CCMP, CSS 1 µF X7R 10% 25V MURATA GRM21BR71E105KA01L
1 CREF 0.01 µF X7R 10% 25V MURATA GRM21BR71E103KA01L
1 CF 0.1 µF X7R 10% 25V MURATA GRM21BR71E104KA01L
0 CFS DNP
4 CIN 4.7 µF X7R 10% 100V TDK C5750X7R2A475K
1 CNTC 10 µF X7R 10% 10V MURATA GRM21BR71A106KE51L
4 COUT 10 µF X7R 10% 50V TDK C4532X7R1H106K
1 COV 47 pF COG/NPO 5% 50V AVX 08055A470JAT2A
1 D1 Schottky 100V 12A VISHAY 12CWQ10FNPBF
1 D2 Zener 10V 500mA ON-SEMI BZX84C10LT1G
1 L1 68 µH 20% 4.3A COILCRAFT MSS1278-683MLB
2 Q1, Q2 NMOS 100V 32A FAIRCHILD FDD3682
1 Q3 NMOS 60V 260mA ON-SEMI 2N7002ET1G
1 Q4 PNP 40V 200mA FAIRCHILD MMBT5087
1 Q5 PNP 150V 600 mA FAIRCHILD MMBT5401
1 Q6 NPN 300V 600mA FAIRCHILD MMBTA42
1 Q7 NPN 40V 200mA FAIRCHILD MMBT6428
3 RBIAS, RREF1, RREF2 49.9 kΩ 1% VISHAY CRCW080549K9FKEA
1 RCSH 12.4 kΩ 1% VISHAY CRCW080512K4FKEA
1 RFS 0Ω 1% VISHAY CRCW08050000Z0EA
3 RGAIN, RT, RUV2 10.0 kΩ 1% VISHAY CRCW080510K0FKEA
2 RHSP, RHSN 1.0 kΩ 1% VISHAY CRCW08051K00FKEA
1 ROV1 15.8 kΩ 1% VISHAY CRCW080515K8FKEA
1 ROV2 499 kΩ 1% VISHAY CRCW0805499KFKEA
1 RPU 4.99 kΩ 1% VISHAY CRCW08054K99FKEA
1 RSER 499Ω 1% VISHAY CRCW0805499RFKEA
1 RSNS 0.2Ω 1% 1W VISHAY WSL2512R2000FEA
1 RSLP 24.3 kΩ 1% VISHAY CRCW080524K3FKEA
1 RUV1 1.43 kΩ 1% VISHAY CRCW08051K43FKEA
1 RUVH 17.4 kΩ 1% VISHAY CRCW080517K4FKEA