JAJU633 October   2018

 

  1.    概要
  2.    リソース
  3.    特長
  4.    アプリケーション
  5.    デザイン・イメージ
  6. 1System Description
    1. 1.1 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Highlighted Products
      1. 2.2.1 TPS92692-Q1
    3. 2.3 LM74700
    4. 2.4 System Design Theory
      1. 2.4.1 Design Procedure
        1. 2.4.1.1  Operating Parameters, Duty Cycle
        2. 2.4.1.2  Setting the Switching Frequency
        3. 2.4.1.3  Inductor Value Calculation
        4. 2.4.1.4  Peak Inductor Current
        5. 2.4.1.5  Calculating RIS (R9)
        6. 2.4.1.6  Minimum Output Capacitance
        7. 2.4.1.7  Setting the LED Current
        8. 2.4.1.8  Soft-Start Capacitor
        9. 2.4.1.9  Overvoltage Protection (OVP)
        10. 2.4.1.10 Main N-Channel MOSFET Selection
        11. 2.4.1.11 Rectifier Diode Selection
        12. 2.4.1.12 Thermal Protection
      2. 2.4.2 Designing for Low EMI
        1. 2.4.2.1 EMI Performance
        2. 2.4.2.2 EMI Filter Design
          1. 2.4.2.2.1 Additional EMI Considerations
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Required Hardware and Software
    2. 3.2 Testing and Results
      1. 3.2.1 Test Setup
      2. 3.2.2 Test Results
        1. 3.2.2.1 Nominal Operation Waveforms
          1. 3.2.2.1.1 Loop Stability Measurements Block Diagram
        2. 3.2.2.2 Efficiency and Line Regulation: Done for different power level for Boost (Hi Beam and Lo Beam) or Boost to Battery for Lo Beam only
        3. 3.2.2.3 Thermal Scan
  9. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
    3. 4.3 Layout Prints
    4. 4.4 Altium Project
    5. 4.5 Gerber Files
    6. 4.6 Assembly Drawings
  10. 5Related Documentation
    1. 5.1 商標

1.1 Key System Specifications

Table 1. Key System Specifications

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
INPUT CHARACTERISTICS
VIN input voltage (nominal) 8 13 16 V
VIN input voltage (min or max) Warm crank or load dump 6 42 V
VIN undervoltage lockout 4.4 V
OUTPUT CHARACTERISTICS
LED forward voltage 3.2 V
Number of LED in series 8 14
VLED output voltage LED+ to LED– (3-V for low beam mode) 3 44 V
ILED output current seven LEDs for high beam and seven LEDs for low beam, IOUT = 1.25 A 1.18 1.25 1.31 A
Output power 55 W
PWM dimming range
SYSTEM CHARACTERISTICS
Output overvoltage protection level 62 V
Overvoltage hysteresis 3 V
fSW switching frequency 275 kHz
Efficiency VIN = 13 V, seven LEDs for high beam and seven LEDs for low beam, IOUT = 1.25 A 91%
VIN = 13 V, seven LEDs for low beam, IOUT = 1.25 A 86%
EMI (conducted) CISPR-25 Class 3 without shield and Class 5 with shield
BASE BOARD CHARACTERISTICS
Form factor 4.0" L × 3.8" W
Number of layers 4
Height Including heat sink and shield 1.7"