Dual-input Charger Ic Operates From Usb Or Wall Adapter

摘要

Advanced Analogic Technologies has introduced the AAT3691 dual-input battery-charger IC with overvoltage protection to 28V with a response time of less than 1 μsec. The IC assesses which input source offers minimum charging timernand modifies the charge path accordingly. It can operate from ac-adapter inputs and USB (universal-serial-bus) ports across a 3 to 6.75V range. You can choose external resistors to set charge current as high as 1.6A from the wall-adapter input and 0.5A from the USB input. Whenever the wall-adapter or USB input power exceeds 6.75V, an in-ternal series switch opens, preventing damage to the battery or charging circuit. The power path's on-resistance is 600 mil. An input feature lets you suspend charging if no cell is present and protects the circuit from defective battery traces or connectors.