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General Description

The MAX4881–MAX4884 overvoltage protection (OVP)

controllers with built-in current-limited switch, protect low-

voltage systems against voltages of up to 28V. When the

input voltage exceeds the overvoltage trip level of 5.6V

(MAX4881/MAX4883) or 4.5V (MAX4882/MAX4884), the

external n-channel MOSFET is turned off to prevent dam-

age to the protected components. An undervoltage/over-

voltage flag indicator (OV) notifies the processor that an

undervoltage/overvoltage fault condition is present.

The MAX4881/MAX4882 feature an internal 1.1A cur-

rent-limited switch, while the MAX4883B/MAX4883C/

MAX4884B/MAX4884C include an internal 0.7A current-

limited switch. When the load current is at the current

limit for longer than the blanking time, the switch of the

MAX4881/MAX4882/MAX4883B/MAX4884B latches off

and does not turn back on until EN, CB, or IN is cycled.

A current-limit flag (FLAGI) asserts to indicate a current

fault condition.

The MAX4883C/MAX4884C limit the current to 0.7A

indefinitely until the thermal protection trips. An overcur-

rent flag output asserts to indicate a current fault condi-

tion after the blanking time has elapsed.

The MAX4881–MAX4884 have a control input (CB) that

is used to turn on and off the internal current-limited

switch. Other features include a shutdown function (EN)

to disable the external n-channel MOSFET, and a built-

in startup delay to allow the adapter voltage to settle

down before turning on the MOSFET.

The MAX4881–MAX4884 is offered in a space-saving

10-pin TDFN package and is specified for operation

over the extended -40°C to +85°C temperature range.

Applications

Features

♦ Overvoltage Protection Up to 28V

♦ Preset Overvoltage Trip Level

5.6V (MAX4881/MAX4883)

4.5V (MAX4882/MAX4884)

♦ Internal Current-Limited Switch

1.1A (MAX4881/MAX4882)

0.7A (MAX4883/MAX4884)

♦ Drives Low-Cost n-Channel MOSFET

♦ Internal 50ms Startup Delay

♦ Overvoltage Fault OV Indicator

♦ Current-Limit Fault FLAGI Indicator

♦ Undervoltage Lockout

♦ Thermal Shutdown Protection

♦ Tiny 10-Pin TDFN Package

MAX4881–MAX4884

Overvoltage Protection Controllers with

Current Limit in TDFN

________________________________________________________________ Maxim Integrated Products 1

FLAGI

GND

BTB

MAX4881

MAX4882

MAX4883

MAX4884

N.C.

GATE

BTA

3mm x 3mm TDFN

TOP VIEW

134

10 8 7

Pin Configuration

Ordering Information

19-3777; 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

OV TRIP LEVEL

(V)

CURRENT LIMIT

(A)

CURRENT-LIMIT

MODE

TOP

MARK

MAX4881ETB -40°C to +85°C 10 TDFN-EP* 5.6 1.1 LATCH-OFF APK

MAX4882ETB -40°C to +85°C 10 TDFN-EP* 4.5 1.1 LATCH-OFF APL

MAX4883BETB -40°C to +85°C 10 TDFN-EP* 5.6 0.7 LATCH-OFF APM

MAX4883CETB** -40°C to +85°C 10 TDFN-EP* 5.6 0.7 CONTINUOUS APN

MAX4884BETB** -40°C to +85°C 10 TDFN-EP* 4.5 0.7 LATCH-OFF APO

MAX4884CETB** -40°C to +85°C 10 TDFN-EP* 4.5 0.7 CONTINUOUS APP

Cell Phones

Digital Still Cameras

PDAs and Palmtop Devices

MP3 Players

* EP = Exposed pad

**Future product—contact factory for availability.

Summary of content (12 pages)

PAGE 1
9-3777; Rev 0; 7/05 Overvoltage Protection Controllers with Current Limit in TDFN ♦ Overvoltage Protection Up to 28V ♦ Preset Overvoltage Trip Level 5.6V (MAX4881/MAX4883) 4.5V (MAX4882/MAX4884) ♦ Internal Current-Limited Switch 1.1A (MAX4881/MAX4882) 0.
PAGE 2
MAX4881–MAX4884 Overvoltage Protection Controllers with Current Limit in TDFN ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) IN ............................................................................-0.3V to +30V GATE ......................................................................-0.3V to +12V EN, CB, OV, FLAGI, BTA, BTB ................................-0.3V to +6V Continuous Power Dissipation (TA = +70°C) 10-Pin TDFN (derate 18.5mW/°C above +70°C) .....1481.
PAGE 3
Overvoltage Protection Controllers with Current Limit in TDFN (VIN = +5V (MAX4881/MAX4883), VIN = +4V (MAX4882/MAX4884), TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 28 V INPUT VOLTAGE (IN) Input Voltage Range Overvoltage Trip Level VIN OVLO 1.2 VIN rising MAX4881/MAX4883 5.5 5.6 5.7 MAX4882/MAX4884 4.4 4.5 4.
PAGE 4
Typical Operating Characteristics (VIN = 5V, TA = +25°C, unless otherwise noted.) 250 200 150 100 MAX4881 toc03 MAX4881 toc02 300 9 250 200 150 100 UVLO TRIP POINT 6 3 50 UVLO TRIP POINT 50 OVLO TRIP POINT GATE VOLTAGE (V) OVLO TRIP POINT 12 0 0 0 5 10 15 20 INPUT VOLTAGE (V) 25 -40 30 GATE VOLTAGE vs. INPUT VOLTAGE (MAX4881) -15 10 35 TEMPERATURE (°C) 60 0 85 0 MAX4881 toc04 1000 OVLO TRIP POINT UVLO TRIP POINT 100 BTB OFF CURRENT (nA) 9 6 3 VEN = 0 VCB = 0 VBTB = 5.
PAGE 5
Overvoltage Protection Controllers with Current Limit in TDFN CURRENT LIMIT vs. TEMPERATURE (MAX4884) MAX4881 toc10 700 1.25 1.00 CURRENT LIMIT (A) CURRENT LIMIT (mA) 600 500 400 300 200 VIN = 4.4V VBTB = 2.7V VCB = 5V 100 -15 0.75 0.50 VIN = 5V VBTB = 2.7V VCB = 5V 0.25 0 -40 MAX4881 toc11 800 CURRENT LIMIT vs. TEMPERATURE (MAX4881) 10 35 TEMPERATURE (°C) 60 0 85 -40 CURRENT LIMIT vs. VBTB (MAX4884) 10 35 TEMPERATURE (°C) 60 85 CURRENT LIMIT vs. VBTB (MAX4881) 700 1.
PAGE 6
Overvoltage Protection Controllers with Current Limit in TDFN MAX4881–MAX4884 Pin Description 6 PIN NAME FUNCTION 1 IN Input. IN is the power input for the OVP charge pump. Bypass IN to GND with a 1µF capacitor or larger. 2 EN Active-Low Enable Input. Drive EN high to turn off the external MOSFET. Driving EN low activates the OVP circuitry and turns on the external MOSFET. 3 GATE 4 BTA Internal Current-Limited Switch Terminal. Connect BTA to the source of the external n-channel MOSFET.
PAGE 7
Overvoltage Protection Controllers with Current Limit in TDFN MAX4881–MAX4884 5V VIN VUVLO VIN tGON 1.2V VOVLO 0V 8V tOVP tSTART 80% VGATE 0.3V IGATE t0V-BLANK 2.4V VOV Figure 3. Power-Up Overvoltage Timing Diagram Figure 1. Startup Timing Diagram 7V/8V VIN VOVLO 4V/5V tOV VEN 2.4V tGOFF tDIS VGATE VGATE 0.3V 0.3V VOV 0.4V Figure 2. Shutdown Timing Diagram Detailed Description The MAX4881–MAX4884 provide up to +28V overvoltage protection for low-voltage systems.
PAGE 8
MAX4881–MAX4884 Overvoltage Protection Controllers with Current Limit in TDFN tBLANK tBLANK tBLANK tBLANK CURRENT LIMIT LOAD CURRENT LOAD CURRENT ON ON SWITCH STATUS SWITCH STATUS OFF OFF EN STATUS FLAGI FLAGI PIN STATUS (a) MAX4881/MAX4882/MAX4883B/MAX4884B tBLANK (a) tBLANK tBLANK tBLANK CURRENT LIMIT LOAD CURRENT LOAD CURRENT ON ON SWITCH STATUS SWITCH STATUS OFF CB STATUS FLAGI (b) MAX4883C/MAX4884C FLAGI STATUS (b) Figure 5.
PAGE 9
Overvoltage Protection Controllers with Current Limit in TDFN OV FLAGI GATE IN OVLO UVLO CHARGE PUMP IN BTA OV BTA UVLO 1.1A/0.7A LIMIT IREF FLAGI EN GATE IN OVLO UVLO CHARGE PUMP BTA BTA UVLO 1.1A/0.7A LIMIT IREF CHARGE PUMP CHARGE PUMP BTB BTB BLANKING TIME AND LATCH-OFF LOGIC CB BLANKING TIME LOGIC CB MAX4881/MAX4882 MAX4883B/MAX4884B MAX4883C/MAX4884C GND GND Figure 7a.
PAGE 10
Table 1. MOSFET Suggestions PART CONFIGURATION/ PACKAGE VDS MAX (V) RON AT 4.5V (mΩ) Si1426DH Single/SC70-6 30 115 Vishay Siliconix http://www.vishay.com (402) 563-6866 FDG315N Single/SC70-6 30 160 Fairchild Semiconductor http://www.fairchildsemi.com (207) 775-8100 RC 1MΩ CHARGE-CURRENTLIMIT RESISTOR HIGHVOLTAGE DC SOURCE Cs 100pF MANUFACTURER RC 50Ω to 100Ω RD 1.
PAGE 11
Overvoltage Protection Controllers with Current Limit in TDFN IN VIO GATE IN GATE BTA BTA VIO 1.1A/0.7A 1.1A/0.7A LOAD BTB BTB MAX4881/ MAX4883 MAX4882/ MAX4884 Li+ BATTERY CHARGER LOAD Li+ FLAGI OV CB EN FLAGI OV CB EN GND GND Figure 12. Connection to an AC-DC Adapter without a Built-In Battery Charger Figure 13. Connection to an AC-DC Adapter with a Built-In Battery Charger electrical ground connection or ground return. Use GND (pin 6) as the only electrical ground connection.
PAGE 12
Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 6, 8, &10L, DFN THIN.EPS MAX4881–MAX4884 Overvoltage Protection Controllers with Current Limit in TDFN D2 D A2 PIN 1 ID N 0.35x0.35 b PIN 1 INDEX AREA E [(N/2)-1] x e REF. E2 DETAIL A e k A1 CL CL A L L e e PACKAGE OUTLINE, 6,8,10 & 14L, TDFN, EXPOSED PAD, 3x3x0.