The LTC4054-4.2V from Linear Technology is a compact, high-efficiency, standalone linear charger for single-cell lithium-ion batteries. This small and versatile charging solution is designed for portable applications where space and simplicity are of paramount importance.

Key Features

• Charge Voltage: Specifically tailored for 4.2V lithium-ion batteries, ensuring the optimal charge for these types of cells.
• Programmable Charge Current: The charge current can be set externally with a single resistor, giving designers flexibility in their applications.
• No External MOSFET, Sense Resistor, or Blocking Diode Required: This integrated approach simplifies the design and reduces the bill of materials for the charging circuit.
• Thermal Regulation: Maximizes the charge rate without the risk of overheating, providing safe operation across various environmental conditions.

Applications

• Portable Devices
• Wearable Technology
• Medical and Fitness Devices
• Bluetooth Applications

Performance Characteristics

The LTC4054-4.2V offers a high level of integration, which results in a simple and efficient charging solution. The device operates over a wide input voltage range and has a final float voltage accuracy of ±1%. The charging current is programmable up to 800mA, making it suitable for a wide range of battery capacities.

Safety and Protection

Safety features include thermal regulation, which prevents the charger from overheating, and a charge termination circuit that conserves power once charging is complete. The LTC4054-4.2V also includes an automatic recharge feature, ensuring the battery remains fully charged over time.

Package and Availability

The LTC4054-4.2V is available in a small SOT-23 package, ideal for space-constrained applications. It is a cost-effective solution for single-cell lithium-ion battery charging, providing a straightforward and reliable charging process without the need for complex circuitry.