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

8.2.5.2 Detailed Design Procedure

Table 4. 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
3 CCMP, CREF, CSS 1 µF X7R 10% 25V MURATA GRM21BR71E105KA01L
1 CNTC 0.33 µF X7R 10% 25V MURATA GRM21BR71E334KA01L
1 CFS 0.1 µF X7R 10% 25V MURATA GRM21BR71E104KA01L
4 CIN 4.7 µF X7R 10% 100V TDK C5750X7R2A475K
4 COUT 10 µF X7R 10% 50V TDK C4532X7R1H106K
1 COV 47 pF COG/NPO 5% 50V AVX 08055A470JAT2A
1 D1 Schottky 60V 5A COMCHIP CDBC560-G
1 L1 47 µH 20% 5.3A COILCRAFT MSS1278-473MLB
1 Q1 NMOS 60V 8A VISHAY SI4436DY
1 Q2 NPN 40V 200 mA FAIRCHILD MMBT3904
1 Q3, Q4 (dual pack) Dual PNP 40V 200mA FAIRCHILD FFB3906
1 RADJ 100 kΩ potentiometer BOURNS 3352P-1-104
1 RBIAS 9.76 kΩ 1% VISHAY CRCW08059K76FKEA
1 RBIAS2 17.4 kΩ 1% VISHAY CRCW080517K4FKEA
3 RCSH, ROV1, RUV1 12.4 kΩ 1% VISHAY CRCW080512K4FKEA
1 RFS 10Ω 1% VISHAY CRCW080510R0FKEA
1 RGAIN 6.55 kΩ 1% VISHAY CRCW08056K55FKEA
3 RHSP, RHSN, RMAX 1.0 kΩ 1% VISHAY CRCW08051K00FKEA
1 RLIM 0.06Ω 1% 1W VISHAY WSL2512R0600FEA
1 ROV2 499 kΩ 1% VISHAY CRCW0805499KFKEA
2 RREF1, RREF2 49.9 kΩ 1% VISHAY CRCW080549K9FKEA
2 RSLP, RT 10.0 kΩ 1% VISHAY CRCW080510K0FKEA
1 RSNS 0.15Ω 1% 1W VISHAY WSL2512R1500FEA
1 RUV2 100 kΩ 1% VISHAY CRCW0805100KFKEA
1 NTC Thermistor 100 kΩ 5% TDK NTCG204H154J