Linear Single Cell Li-Ion Battery Charger with Input Over Voltage Protection

The RT9526A is a fully integrated low cost single cell Li-ion battery charger ideal for portable applications. The RT9526A is capable of being powered up from AC adapter and USB (Universal Serial Bus) port inputs. The RT9526A enters sleep mode when supplies are removed. The RT9526A optimizes the charging task by using a control algorithm including preconditioning mode, fast charge mode, and constant voltage mode. The charging task will remain in constant voltage mode to hold the battery in a full charge condition. The charge current can be programmed with an external resistor. The internal thermal feedback circuitry regulates the die temperature to optimize the charge rate under all ambient temperatures. The RT9526A features 28V maximum rating voltage for VIN. Under-voltage protection and over-voltage protection are provided for the AC adapter supply. The RT9526A is available in the WDFN-8L 2x3 and SOT-23-6 package to achieve best solution for PCB space and total BOM cost saving considerations.