Single Cell Li-Ion Battery Charger with Adjustable Charging Current for Portable Applications

RT9527

The RT9527 is a low cost single-cell Li-ion charger for low current charge applications.

The RT9527 can be powered up from an AC adapter or USB (Universal Serial Bus) port inputs. The RT9527 enters sleep mode when VIN power is removed. The RT9527 optimizes the charging task by using a control algorithm, which includes pre-charge mode, fast-charge mode and constant voltage mode. The charging task is kept in constant voltage mode to hold the battery in a full charge condition. The charge current is adjustable via an external resistor. The internal thermal feedback circuitry regulates the die temperature to optimize the charge rate for all ambient temperatures. The RT9527 features 28V maximum rating voltages for VIN. Other features include under voltage protection and over voltage protection for the AC adapter supply.

The RT9527 is available in a WDFN-8L 2x2 package. The recommended junction temperature range is -40°C to 125°C, and the ambient temperature range is -40°C to 85°C.

Applications

Cellular Phones
Digital Cameras
PDAs and Smart Phone
Portable Instruments

Key Spec.

	RT9527
Status	Active
Vin (min) (V)	4.4
Vin (max) (V)	6
Battery Charge Voltage (max) (V)	4.2
Battery Charge Current (max) (A)	0.6
Status Indicator	Yes
Charger Type	Linear
Input Source	AC Adapter;USB
Features	Internal Compensation;OVP;Power Good;UVP
Package Type	WDFN2x2-8
Built-in Power MOSFETs	Yes