LTC4054

The LTC4054 from Analog Devices is a versatile single-cell lithium-ion battery charger designed for portable applications. It integrates a complete constant-current/constant-voltage linear charger, simplifying circuit design with its low external component count and ThinSOT packaging.

This charger operates with a nominal charge voltage of 4.2V and is designed to meet USB power standards. The integrated MOSFET architecture eliminates the need for external sensing resistors and blocking diodes. Thermal feedback is employed to manage die temperature during high power or high ambient temperature conditions, ensuring reliable operation.

The LTC4054 automatically terminates the charge cycle when the charge current drops to 1/10th of the programmed value after reaching the final float voltage. It also features a low current state (less than 2µA) when the input supply is disconnected and can be switched to a shutdown mode that reduces supply current to 25µA. Additional features include charge current monitoring, undervoltage lockout, automated recharge, and a status pin for charge termination and input voltage presence.

With an operating temperature range of -40°C to 85°C and available in a TSOT-23-5 package, the LTC4054 is suitable for a wide array of battery-powered devices.