MSKSEMI TP4057-MS

A complete constant-current/constant-voltage linear charger IC for single-cell lithium-ion batteries. The SOT package and minimal external component count make it ideal for portable applications. Designed to operate within USB power specifications. Employs an internal MOSFET architecture, eliminating the need for external sense resistors and blocking diodes. Thermal feedback regulates the charge current to limit die temperature during high-power operation or elevated ambient temperatures. Charge voltage is fixed at 4.2V, and charge current is externally programmable via a single resistor. The charge cycle terminates automatically when the charge current drops to 1/10 of the programmed value after the final float voltage is reached. When the input voltage is removed, the device automatically enters a low-current state, reducing battery drain current to below 2μA. A shutdown mode is available to reduce supply current to 25μA. Additional features include a charge current monitor, undervoltage lockout, automatic recharge, and a status pin for indicating charge termination and input voltage presence.

• Programmable charge current up to 500mA
• No MOSFET, sense resistors, or blocking diodes required
• Complete linear charger IC for single-cell Li-Ion batteries in SOT package
• Constant-current/constant-voltage operation with thermal regulation for maximizing charge rate without risk of overheating
• Charges Li-Ion batteries directly from USB port
• 4.2V preset charge voltage with 1% accuracy
• Charge current monitor output for battery fuel gauging
• Automatic recharge
• Charge status output pin
• C/10 charge termination
• 25μA supply current in shutdown mode
• 2.9V trickle charge threshold
• Soft-start limits inrush current

• Cellular phones
• PDA
• MP3 players
• Charging docks
• Bluetooth devices
• Portable lithium battery device chargers