The LTC4410 USB power manager IC enables simultaneous battery charging and system operation of a lithium-ion-powered USB peripheral from a USB host. Because the LTC4410 powers the system load directly from the USB's 5-V supply rather than from the battery's 3.6-V terminal, the battery can charge up to 39% faster. More charging current reduces the battery's charging time and ensures a full charge while the peripheral is connected to the USB host device. By managing the total current consumption, the IC permits a one-cell Li-Ion battery-powered USB peripheral to charge its battery and operate its system circuitry without exceeding a user-set current limit. Applications include USB-certified Li-Ion powered devices like portable printers, digital cameras, cell phones, and PDAs. The manager IC ensures that a portable device complies with USB overcurrent specifications by keeping the total current constant from the USB port. Immediately after the USB cable is detached from the peripheral device, the LTC4410 routes the system load to the battery for seamless and continuous operation of the end-device. The IC is used with the LTC4053 Li-Ion battery charger for USB applications or with the LTC1733 for general-purpose Li-Ion battery charging. Housed in a ThinSOT package, the LTC4410 starts at $1.20 each in 1000-piece lots.
Linear Technology Corp.
www.linear.com; (408) 432-1900