Rainbow Electronics MAX4880 - Manual

General Description
The MAX4880 is an overvoltage-protection controller
with an internal current-limited switch that can be con-
figured as a low-cost battery charger. When the input
voltage exceeds the overvoltage trip level (5.7V), or
drops below the undervoltage-lockout level (4.2V), the
MAX4880 turns off the external n-channel MOSFET and
asserts an undervoltage/overvoltage flag indicator
(
FLAGV) low to notify the processor.
The MAX4880 internal current-limited switch limits the
charge current flowing to the battery to 525mA. The
switch opens when the battery voltage reaches its full-
charged state (4.2V), and a flag (
BAT_OK) asserts to
notify the processor. The MAX4880 includes a switch-
control input (CB) to turn off the internal current-limited
switch, regardless of the battery voltage.
The MAX4880 also features a built-in startup delay that
allows the adapter voltage to settle down before turning
on the MOSFET. Other features include 15kV ESD pro-
tection for the input and a shutdown function (
EN) to
turn off the external n-channel MOSFET.
The MAX4880 is available in a space-saving 10-pin
TDFN package and is specified for operation over the
extended -40°C to +85°C temperature range.
Applications
Cell Phones
Digital Still Cameras
PDAs and Palmtop Devices
MP3 Players
Features
♦ Overvoltage Protection Up to 28V
♦ Preset 5.6V Overvoltage Trip Level
♦ Internal 525mA Current-Limited Switch
♦ ±1.2% Accurate Battery Disconnect (4.2V)
♦ Drives Low-Cost n-Channel MOSFET
♦ Internal 50ms Startup Delay
♦ Overvoltage/Undervoltage-Fault FLAGV Indicator
♦ Battery-Voltage-Trip BAT_OK Indicator
♦ Undervoltage Lockout
♦ Thermal Shutdown Protection
♦ Tiny 10-Pin TDFN Package
MAX4880
Overvoltage-Protection Controller with
Internal Disconnect Switch
________________________________________________________________ Maxim Integrated Products 1
FLAGV GND BTB BTB_SNS
MAX4880
BAT_OK
IN
GATE
BTA
EN
3mm x 3mm TDFN
TOP VIEW
CB
1 3 4
10 8 7
2
9
5
6
Pin Configuration
Ordering Information
AC-DC
ADAPTER
5.25V
GATE IN
FLAGV
BAT_OK BTB_SNS
Li+
BTB
BTA
CB
EN
GND
DC-DC
CONVERTER
V IO
MAX4880
Typical Operating Circuit
19-3776; Rev 0; 7/05
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.
PART TEMP RANGE
PIN-
PACKAGE TOP
MARK
MAX4880ETB -40°C to +85°C 10 TDFN-EP* APJ
* EP = Exposed Pad