HE4054B

HE4054B is a high-performance single-cell lithium-ion battery constant-current/constant-voltage linear charger. The SOT23-5L package combined with minimal external components makes it ideal for portable products and suitable for use with USB power supplies and adapter power supplies. Based on a special internal MOSFET architecture and reverse-charge protection circuitry, no external sense resistors or isolation diodes are required. When the ambient temperature is too high or in high-power applications, thermal feedback regulates the charge current to reduce the chip temperature. The charge voltage is fixed at 4.2V, while the charge current can be externally set via a single resistor. When the charge current drops to 1/10 of the programmed value after reaching the final float voltage, the chip terminates the charge cycle. When the input voltage is disconnected, the HE4054B enters sleep mode, reducing battery leakage current to below 1μA. It can also be configured in shutdown mode, where the quiescent current drops to 25μA. Additional features include: undervoltage lockout, automatic recharge, and charge status indication.

Applications

• Mobile phones, PDAs, MP3 players
• Bluetooth applications
• Single-cell Li-ion battery charging devices

Key features

• SOT-23-5L package
• Programmable charge current up to 500mA
• No MOSFET, sense resistor, or blocking diode required
• Compact form factor for complete linear Li-ion battery charge management
• CC/CV operation with thermal regulation for maximum battery management efficiency without thermal runaway risk
• Single-cell Li-ion battery management via USB interface
• 4.2V preset charge voltage with ±1% accuracy
• Charge current output monitoring
• Charge status indicator
• 1/10 charge current termination
• 25μA supply current in shutdown mode
• 2.9V trickle charge threshold voltage
• Soft-start for inrush current limiting
• Reverse battery polarity protection
• Battery undervoltage protection for charge activation