Linear Technology LTC4057ES5-4.2 Battery Charger

The LTC4057ES5-4.2 is a highly integrated battery charger from Linear Technology, designed for single-cell lithium-ion batteries. This compact and efficient charging solution is housed in a small TSOT-23 package, making it an ideal choice for portable applications where space is at a premium. With its advanced features and straightforward implementation, the LTC4057ES5-4.2 stands out as a reliable component for powering modern electronic devices.

Key Features

• Precision Charging: The LTC4057ES5-4.2 offers a precise end-of-charge voltage of 4.2V, which is critical for the longevity and performance of lithium-ion batteries.
• Programmable Charge Current: Users can set the charge current up to 500mA with a single external resistor, allowing for flexibility in the design and optimization of charging speed for specific applications.
• Automatic Recharge: The device includes an automatic recharge feature, initiating a new charge cycle when the battery voltage falls below 4.05V, ensuring the battery remains fully charged.
• Thermal Regulation: To protect the battery and circuitry, the LTC4057ES5-4.2 incorporates thermal regulation, which reduces the charge current if the die temperature rises to a preset threshold.
• Charge Status Output: An onboard charge status output pin provides a simple interface to indicate the charging progress, which can be used to drive an LED or interface with a microcontroller.
• No Blocking Diode Required: Designed with an internal MOSFET, the LTC4057ES5-4.2 eliminates the need for an external blocking diode, reducing component count and simplifying the design.
• Undervoltage Lockout: The device ensures safe operation by not initiating a charge cycle if the input voltage is too low, preventing damage to the charging circuit.

Applications

The LTC4057ES5-4.2 is suitable for a wide range of applications, including but not limited to:

• Portable electronic devices
• Handheld instruments
• Bluetooth headsets
• Stand-alone chargers
• USB-powered gadgets

Overall, the LTC4057ES5-4.2 is a versatile and robust charging solution for lithium-ion batteries, offering designers a high level of performance in a compact package. Its ease of use and comprehensive feature set make it an excellent choice for powering the next generation of portable devices.