Linear Technology LT4054ES5-4.2: A High-Efficiency LDO Battery Charger

The LT4054ES5-4.2 is an advanced linear battery charger designed by Linear Technology, specifically tailored to efficiently charge single-cell lithium-ion batteries. This compact, high-performance component is engineered to provide a simple and reliable charging solution for portable electronic devices.

Key Features:

• Precision Charging: The LT4054ES5-4.2 is equipped with a precision reference voltage of 4.2V, ensuring that the lithium-ion battery is charged accurately to its peak voltage.
• Adjustable Charge Current: Users can set the desired charge current up to a maximum of 800mA by connecting a resistor between the PROG pin and ground, offering flexibility for various battery capacities.
• Thermal Regulation: This feature prevents the charger from overheating by automatically reducing charge current during high power or high ambient temperature conditions, ensuring safe operation and extending the life of the battery.
• No External MOSFET, Sense Resistor or Blocking Diode Required: The integrated internal MOSFET and current sensing eliminates the need for external components, reducing system complexity and saving board space.
• Charge Status Output: The CHRG pin provides a simple interface to indicate the charging status, which can be used to drive an LED or interface with a microcontroller.

Applications:

The LT4054ES5-4.2 is ideal for a wide range of portable electronic applications, such as:

• Cellular Telephones
• Personal Digital Assistants (PDAs)
• Digital Cameras
• MP3 Players
• Portable Medical and Fitness Equipment

Package Information:

The device is available in a compact SOT-23 5-lead package, making it suitable for space-constrained applications. Its small form factor, combined with high integration, allows for minimalist design in portable electronics.

Conclusion:

The LT4054ES5-4.2 from Linear Technology stands out as a high-efficiency, easy-to-use charging solution that streamlines the design process for developers and enhances the end-user experience with its reliable performance and robust feature set.