下列提供了汽车LED系统的参考设计。用MAX15005将8V至16V汽车电池升压至21V,以驱动一串6至8个LED。参考设计的关键参数在下面列出,并给出了所需的详细电路原理图(图1)和材料清单(表1)。
规格
- VIN:8V至16V (连续),40V (瞬态)
- VLED+电源电压:80mA (最大)时21V ±5%
- VLED+负载范围:70mA时10V至20V
- ILED:70mA ±5%
- 亮度调节输入:400Hz,50Ω,集电极开路
- 亮度调节分辨率:3µs
- 开关频率:385kHz
- 工作温度:-40°C至+125°C
Designator | Value | Description | Part | Footprint | Manufacturer | Quantity |
C1, C5, C6, C8, C10 | 1µF/50V | Capacitors | GCM31MR71H105KA55L | 1206 | Murata | 5 |
C2 | 200pF/100V | Capacitor | GRM2165C2A201JA01D | 0805 | Murata | 1 |
C3, C13, C14 | 100pF/50V | Capacitors | GRM2165C1H101JA01D | 0805 | Murata | 3 |
C4, C7, C9 | 100pF/50V | Capacitors | GRM2165C1H101JA01D | 0805 | Murata | 3 |
C11 | 10nF/50V | Capacitor | GRM216R71H103KA01D | 0805 | Murata | 3 |
C12 | 10µF/50V | Capacitor | UUD1H100MCL1GS | SMD | Nichocon | 1 |
D1 | 1A/400V | Diode | S1G | SMA | Fairchild | 1 |
D2 | 200mA/100V | Schottky Diode | BAD41ZFILM | SOD123 | STM | 1 |
D3 | 200mA/30V | Schottky Diode | STM | SOT23 | STM | 1 |
L1 | 470µF/0.86A | Inductor | MSD1260-474 | SMD | Coilcraft | 1 |
Q1 | 1A/100V | n-FET | ZXMN10A07Z | SOT89 | Zetex | 1 |
Q2 | 2A/55V | n-FET | IRLL014NTRPBF | SOT223 | International Rectifier | 1 |
Q3 | 220mA/50V | n-FET | BSS138 | SOT23 | Fairchild | 1 |
R1 | 22.1kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R2, R4, R6 | 100kΩ | Resistors | SMD, 1%, 0.125W | 0805 | Vishay | 3 |
R5 | 6.19kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R7 | 3.65kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R8 | 210kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R3 | 26.7kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R9, R16 | 2kΩ | Resistors | SMD, 1%, 0.125W | 0805 | Vishay | 2 |
R10 | 10Ω | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R11 | 100Ω | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R12 | 8.66kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R13 | .051kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R14 | 1.4kΩ | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R15 | 100Ω | Resistor | SMD, 1%, 0.125W | 0805 | Vishay | 1 |
R17 | 10Ω | Resistor | SMD, 1%, 0.205W | 1206 | Vishay | 1 |
IC1 | MAX15005A | Boost Controller | MAX15005AAUE+ | 16-TSSOP-EP | Maxim | 1 |
IC2 | MAX4400 | Single Op-Amp | MAX4400AXK+ | 5-SC70 | Maxim | 1 |
图2、3和4中的示波器截图显示了3种不同调光输入下的开关波形。