MAX8819A

The MAX8819A is one member of the MAX8819 series.The MAX8819 is a complete power solution for MP3 players and other handheld applications. The IC MAX8819A includes a battery charger, step-down converters, and WLED power. It features an input current-limit switch to power the IC MAX8819A from an AC-to-DC adapter or USB port, a 1-cell lithium ion (Li+) or lithium polymer (Li-Poly) charger,three step-down converters, and a step-up converter with serial step dimming for powering two to six white LEDs.

Features of the MAX8819A are:(1)smart power selector; (2)operates with no battery present; (3)USB/AC adapter one-cell Li+ charger; (4)three 2MHz step-down converters; (5)2 to 6 series WLED driver with dimming control; (6)active-low REG1 reset output; (7)short-circuit/thermal-overload/input undervoltage/overvoltage protection.Battery charge current and input current limit are independently set. Input power not used by the system charges the battery. Charge current is resistor programmable and the input current limit can be selected as 100mA, 500mA, or 1A. Automatic input selection switches the system load from battery to external power. In addition,on-chip thermal limiting reduces the battery charge rate to prevent charger overheating.

The absolute maximum ratings of the MAX8819A can be summarized as:(1)PV13 to SYS:-0.3V to +0.3V;(2)storage temperature:-65 to +150;(3)OVP4 to GND:-0.3V to +33V;(4)LX4 current:750mARMS;(5)junction temperature range:-40 to 125.Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the dMAX8819A at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.When the system load requirements exceed the input current limit, the battery supplies supplemental current to the load through the internal system load switch. If the system load continuously exceeds the input current limit, the battery of MAX8819A does not charge, even though external power is connected. This is not expected to occur in most cases because high loads usually occur only in short peaks. During these peaks, battery energy is used, but at all other times the battery charges.