usb电源为便携式设备充电-usb充电器制作

18 DESIGN SHOWCASE USB 3.3V 5V 1. USB 5V 3.3V LX LBI GND BATT OUT FB 22µH C4 47µF C5 0.1µF MAX1797 5V SHDN LBO C3 47µFR3604kΩ R4 249kΩ N R5 1.3MΩ IN OUT LX FB GND 22µH D1 C7150µFMAX1837 SHDN C6 10µF 5V 3.3V R2 100kΩ L1 L2 BATTIN GND C1 4.7µF Li+ EN SELV SELI C2 2.2µF CHG R1 316Ω CHARGING LED MAX1811 VBATT VBUS D- D+ GND US B CO NN EC TO R 1 2 3 4 R6 10kΩ 500mA 100mA VBATT U1 U2 U3 (D+ D-) (USB) MP3 PDA USB USB 1 USB 3.3V 5V Li+ U1 U2 (VBATT) 5V U3 5V 3.3V Li+ U1 USB SETI 100mA 19 USB SETI 500mA USB SETV 4.2V 4.1V Li+ U1 0.5% CHG LED U2 DC-DC VBATT 5V 450mA Li+ “ ” 2µA VBATT GND ( LBI ) (LBO) (SHDN) U2 Li+ U2 U2 500mΩ Li+ 500mA 250mV U2 0 250mV LBO N FET 1 2.9V VBATT 2.9V LBO SHDN FET FET 1.3MΩ 249kΩ 3.3V, VLBI = 0.85V (U3) 5V 3.3V 250mA 90% EDN USB • USB 4.4V 5.25V 100mA • USB 4.75V 5.25V 500mA • USB USB 4.35V • USB 100mA