LTC4054ST25P: Standalone Linear Li-Ion Battery Charger

The LTC4054ST25P is a high-quality standalone linear battery charger chip designed by Linear Technology, now part of Analog Devices, for single-cell lithium-ion batteries. This compact and efficient charging solution is ideal for portable applications due to its small package size and minimal external component requirements.

Key Features

• Preset Charge Voltage: The LTC4054ST25P comes with a fixed 4.2V charge voltage, which is well-suited for most single-cell Li-Ion batteries.
• Adjustable Charge Current: Users can set the charge current from 1mA to 800mA by selecting the appropriate value of the external resistor (R_PROG).
• Automatic Recharge: The chip initiates a new charging cycle if the battery voltage drops below 4.05V, ensuring the battery remains fully charged.
• Charge Current Monitor: For battery charge status indication, the chip provides a charge current monitor output.
• Thermal Regulation: This feature maximizes the charge rate without the risk of overheating.
• Thermistor Input: An external thermistor can be connected to provide temperature-qualified charging.
• Low Dropout Voltage: The low dropout voltage allows the charging process to continue even with a lower input voltage.
• Automatic Shutdown: The chip enters a low-current state when the charge cycle completes, conserving power.
• No Blocking Diode Required: The internal MOSFET prevents reverse current, eliminating the need for an external diode.
• Small Package: Available in a small SOT-23 package, this chip is suitable for space-constrained applications.

Applications

The LTC4054ST25P is versatile and can be used in various applications, including:

• Portable electronics such as digital cameras, MP3 players, and Bluetooth headsets
• USB-powered devices
• Handheld instrumentation
• Standby and backup batteries
• Embedded systems

With its ease of integration and comprehensive feature set, the LTC4054ST25P is an excellent choice for designers looking to implement a reliable charging solution with minimal design overhead. Its precision and efficiency make it an industry favorite for single-cell Li-Ion battery charging applications.