This document introduces the features of the LTC4081 lithium-ion battery charger, including constant current constant voltage, NTC temperature detection, automatic charging, soft start and other functions
The LTC4081 is a complete constant‑current/constant‑voltage lithium‑ion/polymer battery charger that includes a 300 mA synchronous buck converter. It features programmable charge current up to 500 mA, an internal 4.5‑hour safety timer, NTC thermistor temperature monitoring, and a C/10 charge‑termination indicator.
The device is supplied in a 10‑lead 3 mm × 3 mm DFN package and operates from 2.7 V to 4.5 V input. It offers very low quiescent currents (300 pA charger on, 10 pA regulator off) and works over an operating temperature range of –40 °C to 85 °C.
| Input Voltage Range | 2.7 V to 4.5 V |
|---|---|
| Maximum Output Current (Buck) | 300 mA |
| Programmable Charge Current | Up to 500 mA (5 % accuracy) |
| Shutdown Supply Current | 5 µA |
| Safety Timer | 4.5 hour termination |
| Package | 10‑lead 3 mm × 3 mm DFN |
| Storage Temperature Range | -65 °C to 125 °C |
The LTC4081 can be programmed for a charge current up to 500 mA with 5 % accuracy.
The CHRG pin goes active when the charge current drops to ten percent of the programmed value (C/10).
It is supplied in a 10‑lead plastic DFN package measuring 3 mm × 3 mm.