Datasheet LT3477 (Analog Devices) - 13
| 制造商 | Analog Devices |
| 描述 | 3A, DC/DC Converter with Dual Rail-to-Rail Current Sense |
| 页数 / 页 | 22 / 13 — applicaTions inForMaTion. Figure 7a. 5V to 4 White LEDs: Boost With PWM … |
| 文件格式/大小 | PDF / 585 Kb |
| 文件语言 | 英语 |
applicaTions inForMaTion. Figure 7a. 5V to 4 White LEDs: Boost With PWM Dimming. Figure 7b. PWM Dimming Waveforms
该数据表的模型线
文件文字版本
LT3477
applicaTions inForMaTion
L1 2.0µH D1 V OUT IN 5V C1 C2 3.3µF I 1M 10µF SP1 ISN1 SW VIN FBN IADJ1 75k I FBP ADJ2 SHDN LT3477 VREF I SS SP2 R C SENSE SS 0.33Ω 33nF ISN2 VC R LED1 T GND 6.81k LED2 300mA D2 LED3 5V PWM NMOS1 LED4 0 100Hz RC NMOS2 100k 2.4k CC 10nF 3477 F07a C1: TAIYO YUDEN EMK316BJ335ML C2: TAIYO YUDEN UDK325BJ106MM L1: TOKO D53LC (PN# A915AY-2ROM) D1: ZETEX ZLLS1000 D2: DIODES INC 1N4148 NMOS1: ZETEX 2N7002 NMOS2: FAIRCHILD FDG327N LED1 TO LED4: LUMILEDS LXHL-BW02
Figure 7a. 5V to 4 White LEDs: Boost With PWM Dimming
85 350 EFFICIENCY 80 300 PWM 5V/DIV 75 250 70 200 LED CURRENT IL 1A/DIV 65 150 EFFICIENCY (%) 60 100 I V LED IN = 5V 200mA/DIV 55 BOOST 50 4 LEDs, 300mA PWM FREQUENCY = 100Hz 50 0 3477 F07b 0 20 40 60 80 100 10µs/DIV V PWM DUTY CYCLE (%) IN = 5V PWM FREQ = 100Hz 4 LEDs BOOST 3477 F07c 300mA
Figure 7b. PWM Dimming Waveforms Figure 7c. Efficiency and LED Current vs PWM Duty Cycle
3477fd For more information www.linear.com/LT3477 13 Document Outline Description Typical Application Absolute Maximum Ratings Electrical Characteristics Typical Performance Characteristics Pin Functions Package Description Typical Application Related Parts
applicaTions inForMaTion
L1 2.0µH D1 V OUT IN 5V C1 C2 3.3µF I 1M 10µF SP1 ISN1 SW VIN FBN IADJ1 75k I FBP ADJ2 SHDN LT3477 VREF I SS SP2 R C SENSE SS 0.33Ω 33nF ISN2 VC R LED1 T GND 6.81k LED2 300mA D2 LED3 5V PWM NMOS1 LED4 0 100Hz RC NMOS2 100k 2.4k CC 10nF 3477 F07a C1: TAIYO YUDEN EMK316BJ335ML C2: TAIYO YUDEN UDK325BJ106MM L1: TOKO D53LC (PN# A915AY-2ROM) D1: ZETEX ZLLS1000 D2: DIODES INC 1N4148 NMOS1: ZETEX 2N7002 NMOS2: FAIRCHILD FDG327N LED1 TO LED4: LUMILEDS LXHL-BW02
Figure 7a. 5V to 4 White LEDs: Boost With PWM Dimming
85 350 EFFICIENCY 80 300 PWM 5V/DIV 75 250 70 200 LED CURRENT IL 1A/DIV 65 150 EFFICIENCY (%) 60 100 I V LED IN = 5V 200mA/DIV 55 BOOST 50 4 LEDs, 300mA PWM FREQUENCY = 100Hz 50 0 3477 F07b 0 20 40 60 80 100 10µs/DIV V PWM DUTY CYCLE (%) IN = 5V PWM FREQ = 100Hz 4 LEDs BOOST 3477 F07c 300mA
Figure 7b. PWM Dimming Waveforms Figure 7c. Efficiency and LED Current vs PWM Duty Cycle
3477fd For more information www.linear.com/LT3477 13 Document Outline Description Typical Application Absolute Maximum Ratings Electrical Characteristics Typical Performance Characteristics Pin Functions Package Description Typical Application Related Parts