MAX745EAP+T 电池管理 MAXIM

MAX745EAP+T

电池管理 Switch-Mode Li Battery Charger Lithium-Ion

MAX745EAP+T General Description

The MAX745 provides all functions necessary for charging lithium-ion (Li+) battery packs. It provides a regulated charging current of up to 4A without getting hot, and a regulated voltage with only ±0.75% total error at the battery terminals. It uses low-cost, 1% resistors to set the output voltage, and a low-cost N-channel MOSFET as the power switch.

The MAX745 regulates the voltage set point and charging current using two loops that work together to transition smoothly between voltage and current regulation. The per-cell battery voltage regulation limit is set between 4V and 4.4V using standard 1% resistors, and then the number of cells is set from 1 to 4 by pin-strapping. Total output voltage error is less than ±0.75%.

MAX745EAP+T Features

♦ Charges 1 to 4 Li+ Battery Cells

♦ ±0.75% Voltage-Regulation Accuracy Using 1% Resistors

♦ Provides up to 4A without Excessive Heating

♦ 90% Efficient

♦ Uses Low-Cost Set Resistors and N-Channel Switch

♦ Up to 24V Input

♦ Up to 18V Maximum Battery Voltage

♦ 300kHz Pulse-Width Modulated (PWM) Operation Low-Noise, Small Components

♦ Stand-Alone Operation—No Microcontroller Needed

MAX745EAP+T Applications

Li+ Battery Packs

Desktop Cradle Chargers

Cellular Phones

Notebook Computers

Hand-Held Instruments