LTC4057ES5-4.2#TRMPBF

LTC4057-4.2 is a constant-current/constant-voltage linear charger for single-cell lithium-ion batteries. It is specifically designed to work within USB power specifications. No external sense resistor is needed and no blocking diode is required due to the internal MOSFET architecture. Thermal feedback prevents overheating by regulating the charge current to limit the die temperature during high power operation or high ambient temperature conditions. The charge voltage is preset at 4.2V and the charge current can be programmed externally with a single resistor. It is widely used in applications such as wireless PDAs, cellular phones, portable electronics etc.

• Programmable charge current upto 800mA
• Charges single cell Li-ion batteries directly from USB port
• Preset 4.2V charge voltage with ±1% accuracy
• Current monitor pin for charge termination
• Low battery charge conditioning (trickle charging)
• Soft-start limits inrush current
• Input supply voltage from 4.25V to 6.5V
• Input supply current is 200µA typ at (TA = 25°C, VCC = 5V)
• Regulated output (float) voltage is 4.2V typ at (IBAT = 40mA, 0°C <lt/> TA <lt/> 85°C)
• Operating temperature range from -40°C to 85°C, package style is 5-lead plastic SOT-23

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party