description
LTC®The 4054L is a complete constant-current/constant-voltage linear charger for single-cell Li-Ion batteries. Its small form factor and ability to regulate low charge currents make the LTC4054L ideal for portable applications with low capacity rechargeable coin Li-Ion batteries. Also, the LTC4054L is specifically designed to operate within USB power specifications.
Due to the internal MOSFET architecture, no external sense resistor and isolation diode are required. Thermal feedback regulates the charge current to avoid thermal design that exceeds safety standards. The charge voltage is fixed at 4.2V and the charge current is externally programmable via a single resistor. When the charge current drops to 1/10th of the programmed value after reaching the final float voltage, the LTC4054L automatically terminates the charge cycle.
When the input voltage (AC adapter or USB power) is removed, the LTC4054L automatically enters a low current state and reduces the battery leakage current to less than 2μA. The LTC4054L can be put in shutdown, reducing supply current to 25μA.
Other features of the LTC4054L include a charge current monitor, undervoltage lockout, automatic recharge and a status pin to indicate charge termination and input voltage entry.
apply
- Charger for coin lithium-ion batteries
- Portable MP3 player, wireless headset
- Bluetooth app
- A multifunctional watch