MAX1874 查看數據表（PDF） - Maxim Integrated

零件编号

产品描述 (功能)

生产厂家

MAX1874

Dual-Input, USB/AC Adapter, 1-Cell Li+ Charger with OVP and Thermal Regulation

Maxim Integrated 

19-2912; Rev 1; 2/07

EVAALVUAAILTAIOBNLEKIT

Dual-Input, USB/AC Adapter, 1-Cell

Li+ Charger with OVP and Thermal Regulation

General Description

The MAX1874 charges a single-cell Li+ battery from

both USB and AC adapter sources. It also includes bat-

tery-to-input power switchover, so the system can be

powered directly from the power source rather than

from the battery.

In its simplest application, the MAX1874 needs no

external MOSFET or diodes, and accepts input volt-

ages up to 6.5V; however, DC input overvoltage protec-

tion up to 18V can be added with a single SOT PFET.

On-chip thermal limiting simplifies printed circuit board

(PCB) layout and allows optimum charging rate without

the thermal limits imposed by worst-case battery and

input voltage. When the MAX1874 thermal limit is

reached, the charger does not shut down but simply

reduces charging current.

Ambient or battery temperature can be monitored with

an external thermistor. When the temperature is out of

range, charging pauses.

Other features include a CHG output to indicate when

battery current tapers below a predetermined level. DC

power-OK (DCOK), USB power-OK (UOK), and power-

on (PON) outputs indicate when valid power is present.

These outputs drive logic or power-selection MOSFETs

to disconnect the charging sources from the load and

to protect the MAX1874 from overvoltage.

The MAX1874 contains no logic for communication with

the USB host. It must receive instructions from a local

microcontroller. The MAX1874 is available in a 16-pin

5mm ✕ 5mm thin QFN package and operates over the

-40°C to +85°C temperature range.

Applications

PDAs

Cell Phones

Wireless Appliances Digital Cameras

Pin Configuration

TOP VIEW

16 15 14 13

DCLV 1

DC 2

CHG 3

USEL 4

MAX1874

12 USB

11 BYP

10 PGND

9 REF

5678

Features

♦ Charge from USB or AC Adapter

♦ Automatic Switchover to AC Adapter

♦ Thermal Limiting Simplifies Board Design

♦ Small, High-Power 16-Pin Thin QFN Package

♦ Input Protection Up to 18V

♦ Soft-Start

♦ Automatic Battery-to-Input Load Switch

PART

MAX1874ETE

Ordering Information

TEMP RANGE

-40°C to +85°C

PIN-

PACKAGE

16 Thin QFN

5mm x 5mm

PKG

CODE

T1655-2

Typical Operating Circuit

DC INPUT

USB INPUT

TO REF

DC

MAX1874 PON

DCOK

DCLV

BATT

UOK

USB

CHG

USEL

DCI

EN

REGULATOR REF

Li+

CELL

500mA

100mA

THRM

NTC

THERMISTOR

BYP

PGND GND

THIN QFN

5mm x 5mm

Functional Diagram appears at the end of the data sheet.

________________________________________________________________ Maxim Integrated Products 1

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Share Link: