TP4054LS5

This device is a constant-current/constant-voltage linear charger for single-cell lithium-ion or lithium-polymer batteries. Its simple circuit design makes it ideal for portable applications, with compatibility for both USB and adapter power sources. An integrated reverse-current protection circuit eliminates the need for an external isolation diode. A thermal feedback mechanism automatically adjusts the charge current to limit die temperature under high power dissipation or high ambient temperature conditions. The charge termination voltage is 4.2V, and the charge current is programmable via an external resistor. The charge cycle terminates automatically when the charge current drops to 1/10 of the programmed value. The IC includes an open-drain status indicator output to signal charging status. When the battery voltage is below 2.9V, trickle precharge is applied; once this threshold is exceeded, the device enters constant-current mode; as the battery voltage approaches 4.2V, it transitions to constant-voltage mode with gradually tapering current until charge termination. If the battery voltage falls below the recharge threshold, a new charge cycle begins automatically. An internal high-accuracy voltage reference ensures battery voltage accuracy within ±1%. When the input voltage drops below the UVLO threshold or falls below the battery voltage, the IC enters a low-power sleep mode. An integrated intelligent thermal control function automatically reduces charge current when the junction temperature exceeds 115°C, maximizing the IC's power handling capability while preventing thermal damage.

Applications

• Battery chargers
• Electronic dictionaries
• Mobile phones & PDAs
• Digital cameras
• Portable devices
• MP3 & MP4 players
• Bluetooth & GPS navigation devices

Key features

• Single-cell Li-Ion battery charging
• Programmable charge current up to 500mA
• No external MOSFET required
• Constant current/constant voltage charging mode
• Automatic recharge function
• Precharge voltage accuracy ±1% (4.2V)
• Package: SOT23-5