Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - ELCs High side TSSOP 8

_______________General Description

The MAX891L/MAX892L smart, low-voltage, P-channel,

MOSFET power switches are intended for high-side

load-switching applications. These switches operate

with inputs from 2.7V to 5.5V, making them ideal for

both 3V and 5V systems. Internal current-limiting circuitry

protects the input supply against overload. Thermal-

overload protection limits power dissipation and junc-

tion temperatures.

The MAX891L/MAX892L’s maximum current limits are

500mA and 250mA, respectively. The current limit

through the switch is programmed with a resistor from

SET to ground. When the switch is on, the quiescent

supply current is a low 13µA. When the switch is off, the

quiescent current decreases to 0.1µA.

The MAX891L/MAX892L are available in 8-pin µMAX

packages.

________________________Applications

PCMCIA Slots

Access Bus Slots

Portable Equipment

____________________________Features

♦ Ultra-Small µMAX Package—Only 1.11mm High

♦ 2.7V to 5.5V Input Range

♦ Programmable Current Limit

♦ Low

13µA Quiescent Current at V

= 3.3V,

0.1µA Switch Off

♦ Thermal Shutdown

♦

FAULT Indicator Output

♦ On-Resistances:

0.12Ω (MAX891L)

0.25Ω (MAX892L)

MAX891L/MAX892L

Current-Limited, High-Side

P-Channel Switches with Thermal Shutdown

________________________________________________________________

Maxim Integrated Products

OUT

FAULT

SET

GND

MAX891L

MAX892L

µMAX

TOP VIEW

__________________Pin Configuration

1µF

0.1µF

100k

IN OUTPUTOUTINPUT

IN OUT

FAULT ON

ON/OFF

GND SET

MAX891L

MAX892L

__________Typical Operating Circuit

19-1223; Rev 0; 4/97

PART

MAX891LC/D

0°C to +70°C

TEMP.

RANGE

PIN-

PACKAGE

Dice**

______________Ordering Information

* To order these units in tape and reel, add (-T) to the end of the

part number.

** Dice are tested at T

= +25°C.

For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800

CURRENT

LIMIT

500mA

MAX892LC/D

0°C to +70°C Dice** 250mA

MAX891LEUA* -40°C to +85°C 8 µMAX 500mA

MAX892LEUA* -40°C to +85°C 8 µMAX 250mA

Summary of content (8 pages)

PAGE 1
9-1223; Rev 0; 4/97 Current-Limited, High-Side P-Channel Switches with Thermal Shutdown The MAX891L/MAX892L smart, low-voltage, P-channel, MOSFET power switches are intended for high-side load-switching applications. These switches operate with inputs from 2.7V to 5.5V, making them ideal for both 3V and 5V systems. Internal current-limiting circuitry protects the input supply against overload. Thermaloverload protection limits power dissipation and junction temperatures.
PAGE 2
MAX891L/MAX892L Current-Limited, High-Side P-Channel Switches with Thermal Shutdown ABSOLUTE MAXIMUM RATINGS IN to GND ..................................................................-0.3V to 6V ON, FAULT to GND.................................................... -0.3V to 6V SET, OUT to GND ........................................-0.3V to (VIN + 0.3V) Maximum Continuous Switch Current MAX891L ..........................................................................0.75A MAX892L .........................
PAGE 3
Current-Limited, High-Side P-Channel Switches with Thermal Shutdown MAX891L/MAX892L ELECTRICAL CHARACTERISTICS (VIN = 3V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2) PARAMETER CONDITIONS Operating Voltage MIN 3.0 TYP MAX UNITS 5.5 V Quiescent Current VIN = 5V, ON = GND, IOUT = 0mA 50 µA Off-Supply Current ON = IN, VIN = VOUT = 5.5V 2.2 µA Off-Switch Current ON = IN, VIN = 5.5V, VOUT = 0V 8 µA Undervoltage Lockout Rising edge, 1% hysteresis 2.9 V VIN = 4.
PAGE 4
__________________________________________Typical Operating Characteristics (Typical Operating Circuit, TA = +25°C, unless otherwise noted.) QUIESCENT CURRENT vs. TEMPERATURE 4 2 VIN = 3V 10 9 1 2 3 4 5 -20 20 0 40 60 80 INPUT VOLTAGE (V) TEMPERATURE (°C) OFF-SWITCH LEAKAGE CURRENT vs. TEMPERATURE NORMALIZED ON-RESISTANCE vs. TEMPERATURE 0.03 0.02 0.01 0 -40 -20 20 0 40 60 80 1.2 1200 1.1 1000 1.0 0.9 60 400 0.
PAGE 5
Current-Limited, High-Side P-Channel Switches with Thermal Shutdown (Typical Operating Circuit, TA = +25°C, unless otherwise noted.) CURRENT-LIMIT RESPONSE (MAX891L, RL = 0.8Ω) CURRENT-LIMIT RESPONSE (MAX891L, RL = 0.5Ω) A 5V B B C 5V A 0A 0A C 0V 0V 2µs/div CIN = 47µF, COUT = 0.1µF A: VIN, 500mV/div, AC COUPLED 1µs/div CIN = 47µF, COUT = 0.
PAGE 6
MAX891L/MAX892L Current-Limited, High-Side P-Channel Switches with Thermal Shutdown ______________________________________________________________Pin Description PIN NAME FUNCTION 1, 2 IN Input. P-channel MOSFET source. Bypass IN with a 1µF capacitor to ground. 3 ON Active-Low Switch On Input. A logic low turns the switch on. 4 GND Ground 5 SET Set Current-Limit Input. A resistor from SET to ground sets the current limit for the switch. See Setting the Current Limit section.
PAGE 7
Current-Limited, High-Side P-Channel Switches with Thermal Shutdown MAX891L MAX892L Layout and Thermal-Dissipation Consideration SET RSET GND Figure 2. Setting the Current Limit Thermal Shutdown The MAX891L/MAX892L feature thermal shutdown. The switch turns off when the junction temperature exceeds +135°C. Once the device cools by 10°C, the switch turns back on. If the fault short-circuit condition is not removed, the switch will cycle on and off, resulting in a pulsed output.
PAGE 8
__________________________________________________Tape-and-Reel Information 4.0 ±0.1 1.0 ±0.1 2.0 ±0.05 1.5 +0.1/-0.0 DIAMETER 1.75 ±0.1 A 3.5 ±0.05 8.0 ±0.3 2.2 ±0.1 0.5 RADIUS TYPICAL 4.0 ±0.1 A0 A Bo 0.30 ±0.05 0.8 ±0.05 1.0 MINIMUM Ko Ao = 3.1mm ±0.1 Bo = 2.7mm ±0.1 Ko = 1.2mm ±0.1 NOTE: DIMENSIONS ARE IN MM. AND FOLLOW EIA481-1 STANDARD. 0.30R MAX. ________________________________________________________Package Information 8LUMAXD.