BL BL4056C-42ES

BL4056C is a complete single-cell lithium-ion battery charger using constant-current/constant-voltage linear charging, with battery positive/negative polarity reversal protection and 5V input power positive/negative polarity reversal protection. The ESOP8 package with a bottom heat sink pad and minimal external component count makes it an ideal choice for portable applications. It is compatible with both USB power and adapter power sources. An internal PMOSFET architecture with anti-backflow circuitry eliminates the need for an external isolation diode. Thermal feedback adaptively regulates the charge current to limit die temperature during high-power operation or elevated ambient temperature conditions. The charge termination voltage is selectable between two levels: 4.2V and 4.35V. The charge current can be externally set via a single resistor. The charge cycle terminates automatically when the charge current drops to 1/10 of the programmed value after reaching the final float voltage.

When the input voltage is removed, the device automatically enters a low-current state, reducing battery leakage current to below 0.2µA. Additional features include power supply adaptive control, battery temperature monitoring, undervoltage lockout, automatic recharge, and two LED status pins indicating charging and charge completion.

• Li-ion battery reverse polarity protection (positive/negative)
• Vcc input reverse polarity protection
• Power supply adaptive
• Programmable charge current up to 1000mA
• Constant current/constant voltage
• Temperature-adaptive charge rate maximization
• Preset charge voltage accuracy ±1%
• Automatic recharge
• Dual-output charge status, battery absent and fault status indication
• C/10 charge termination
• Supply current 70uA in standby mode
• 2.9V trickle charge
• Soft-start inrush current limiting
• Battery temperature monitoring
• 8-pin ESOP package

• Mobile phones, PADs
• Digital cameras, electronic dictionaries
• GPS portable devices, various chargers