Rainbow Electronics MAX4995 User Manual

General Description

The MAX4995A/MAX4995AF/MAX4995AL/MAX4995B/
MAX4995C programmable current-limit switches feature
internal current limiting to prevent damage to host
devices due to faulty load conditions. These analog
switches feature a low 130mΩ (typ) on-resistance and
operate from a +1.7V to +5.5V input voltage range. The
current limit is adjustable from 50mA to 600mA, making
these devices ideal for SDIO (secure digital input/out­put) and other load-switching applications.

Each device in the family handles an overcurrent event
differently depending on the option selected. The
MAX4995A/MAX4995AF/MAX4995AL go into an autoretry
mode, the MAX4995B latches off the switch, and the
MAX4995C places the device in a continuous current-limit
mode. Additional safety features include thermal shut­down to prevent overheating and reverse-current blocking
to prevent current from being driven back into the source.

The MAX4995A/MAX4995AF/MAX4995AL/MAX4995B/
MAX4995C are available in a tiny 10-pin, 1.4mm x 1.8mm
UTQFN package and operate over the -40°C to +125°C
extended temperature range.

Applications

SDIO Ports

USB Ports

Notebook VGA Ports

GPS

Cell Phones

MP3 Players

UTCA/ATCA Platforms

Features

♦ 50mA to 600mA Programmable Current Limit

♦ ±10% Accurate Current Limit
♦ Overload FLAG Threshold

♦ Low Dropout Voltage

♦ Short-Circuit Protection

♦ Thermal Shutdown

♦ Reverse-Current Protection

♦ 170µA (typ) Supply Current

♦ +1.7V to +5.5V Supply Voltage Range

♦ Tiny 10-Pin, 1.4mm x 1.8mm UTQFN Package

MAX4995A/AF/AL/MAX4995B/MAX4995C

50mA to 600mA Programmable

Current-Limit Switches

________________________________________________________________

Maxim Integrated Products

1

Ordering Information/Selector Guide

19-4363; Rev 0; 11/08

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.

All devices operate over the -40°C to +125°C temperature range.
+Denotes a lead-free package.
*Future product. Contact factory for availability.
Ordering Information/Selector Guide continued at end of data sheet.

PART

PIN-

PACKAGE

ON POLARITY

OVERCURRENT

RESPONSE

SHORT-CIRCUIT

RESPONSE

TOP MARK

MAX4995AAUK+T* 6 SOT23 ActIve-High Autoretry Normal +ACNZ

MAX4995AAVB+T 10 UTQFN Active-High Autoretry Normal +AAM

MAX4995AFAUK+T*

6 SOT23 Active-High Autoretry Fast +ACOE

MAX4995AFAVB+T 10 UTQFN Active-High Autoretry Fast +AAR

MAX4995ALAUK+T*

6 SOT23 Active-Low Autoretry Normal +ACDA

Typical Operating Circuit appears at end of data sheet.

Pin Configurations

Pin Configurations continued at end of data sheet.

TOP VIEW

* ( ) FOR THE MAX4995AL ONLY.

IN

10 8

MAX4995A/MAX4995AF
MAX4995AL/MAX4995B

35

ON (ON)* GND

1.4mm x 1.8mm

N.C.

9

MAX4995C

4

UTQFN

OUT

7 OUT1IN

6 N.C.2FLAG

SETI

MAX4995A/AF/AL/MAX4995B/MAX4995C

50mA to 600mA Programmable
Current-Limit Switches

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

IN, ON, ON, FLAG, OUT, and SETI to GND .............-0.3V to +6V

Current into Any Pin (Except IN, OUT)................................20mA

OUT Short Circuit to GND .................................................800mA

Continuous Power Dissipation (T

A

= +70°C) (Note 1)
10-Pin UTQFN (derate 6.99mW/ °C above
T

A

= +70°C) ................................................................559mW

Junction-to-Ambient Thermal Resistance (θ

JA

)

(Note 2) ...................................................................143.1°C/W

Operating Temperature Range .........................-40°C to +125°C

Storage Temperature Range .............................-65°C to +150°C

Junction Temperature......................................................+150°C

Lead Temperature (soldering, 10s) .................................+300°C

Note 1: These power limits are defined by the thermal characteristics of the package, maximum function temperature (+150°C), and

the JEDEC51-7 defined setup. Maximum power dissipation could be lower, limited by the thermal-shutdown protection
included in this IC.

Note 2: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-

layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial

.

ELECTRICAL CHARACTERISTICS

(VIN= +1.7V to +5.5V, R

SETI

= 94.3kΩ, CIN= 1µF, and TA= TJ= -40°C to +125°C, unless otherwise noted. Typical values are at VIN= +3.3V,

T

A

= +25°C.)

PARAMETER

CONDITIONS

UNITS

SUPPLY OPERATION

Operating Voltage V

IN

1.7 5.5 V

Quiescent Current I

Q

I

OUT

= 0, switch on, V

IN

= 3.3V

µA

Latchoff Current

VIN = 3.3V, I

OUT

= 0 after an overcurrent

fault (MAX4995B)

815µA

Shutdown Forward Current I

SHDNVON

= 0, VON = VIN, V

IN

= 5.5V, V

OUT

= 0

5µA

Shutdown Reverse Current

V

ON

= 0, VON = VIN, V

IN

= 1.7V,

V

OUT

= 5.5V (current into OUT)

1µA

INTERNAL FET

Switch-On Resistance R

ON

VIN = 3.3V, I

OUT

lower than I

LIM

mΩ

Normalized Current-Limit Accuracy

I

LIM

= 50mA to 600mA, VIN - V

OUT

= 1V,

V

IN

= 3.3V (Note 3)

0.9 1 1.1 —

(R

SETI

+ 2.48) x I

LIM

Product

I

LIM

= 50mA to 600mA, VIN - V

OUT

= 1V,

V

IN

= 3.3V

V

Reverse Blocking Current

V

OUT

> V

IN

+ 300mV after reverse-current-

limit shutdown

10 µA

Reverse Blocking Threshold

V

OUT

= V

IN

+ 300mV, OUT falling until switch

turns on

35

mV

FLAG Assertion Drop Voltage
Threshold

V

FA

Increase (VIN - V

OUT

) drop until FLAG

asserts, I

OUT

limiting, VIN = 3.3V

mV

ON, ON INPUT

ON, ON Input Leakage I

LEAK

VON, VON = V

IN

or GND -1 +1 µA

ON, ON Input Logic-High Voltage V

IH

1.6 V

ON, ON Input Logic-Low Voltage V

IL

0.4 V

FLAG OUTPUT

FLAG Output Logic-Low Voltage I

SINK

= 1mA 0.4 V

FLAG Output Leakage Current V

IN

= V

FLAG

= 5.5V, FLAG deasserted 1 µA

SYMBOL

MIN TYP MAX

170 300

I

LATCH

I

RSHDN

26138 29042 31946

0.01

0.01

130 350

110 210

650

MAX4995A/AF/AL/MAX4995B/MAX4995C

50mA to 600mA Programmable

Current-Limit Switches

_______________________________________________________________________________________ 3

Note 3: I

LIM

is forward current limit.

Note 4: Turn-on time and turn-off time are defined as the difference in the time between when the output crosses 10% and 90%

of the final output voltage.

Note 5: Blanking time and retry time are generated by the same oscillator. Therefore, the ratio of

is a constant value of 32. See Figures 2 and 3.

t
t

RETRY

BLANK

I (mA)

2

R(k 2.48k

LIM

SETI

=

+

9042( )

)()

V

ΩΩ

ELECTRICAL CHARACTERISTICS (continued)

(VIN= +1.7V to +5.5V, R

SETI

= 94.3kΩ, CIN= 1µF, and TA= TJ= -40°C to +125°C, unless otherwise noted. Typical values are at VIN= +3.3V,

T

A

= +25°C.)

PARAMETER

CONDITIONS

UNITS

DYNAMIC

Turn-On Time t

SS

V

IN

= 3.3V, C

OUT

= 1µF, RL = 20Ω, Figure 1,

(Note 4)

µs

Turn-Off Time t

OFF

S w i tch fr om on to off, V

I N

= 3.3V , C

OU T

= 1µF,

R

L

= 20Ω, Figure 1 (Note 4)

µs

5

Current-Limit Reaction Time t

LIM

V

IN

= 3.3V, R

SETI

=
578kΩ, output high
and then short-circuit
applied

MAX4995AF 1.5

µs

Blanking Time

(Note 5) 10

ms

Retry Time

ms

THERMAL PROTECTION

Thermal Shutdown

°C

Thermal-Shutdown Hysteresis 15 °C

t

SS

10%

90%

10%

90%

t

OFF

V

OUT

Figure 1. Timing Diagram for Measuring Turn-On Time (tSS) and Turn-Off Time (t

OFF

).

SYMBOL

t

BLANK

t

RETRY

MAX4995A/AL/B/C

M AX 4995A/M AX 4995AF/M AX 4995AL ( N ote 5) 320 723.2

MIN TYP MAX

120

120

16.3 22.6

+150

MAX4995A/AF/AL/MAX4995B/MAX4995C

50mA to 600mA Programmable
Current-Limit Switches

4 _______________________________________________________________________________________

CURRENT LIMIT

vs. SUPPLY VOLTAGE

MAX4995A toc01

SUPPLY VOLTAGE (V)

CURRENT LIMIT (mA)

2.0 3.02.5 4.5 5.03.5 4.0

290

295

300

305

310

315

285

1.5 5.5

MAX4995AL

NORMALIZED CURRENT LIMIT

vs. TEMPERATURE

MAX4995A toc02

TEMPERATURE (°C)

NORMALIZED CURRENT LIMIT

-25 5-10 20

0.950

0.975

1.000

1.050

0.925

1.025

1.075

1.100

0.900

-40 50 8065 95 11035 125

MAX4995AL

μ

μ

QUIESCENT SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX4995A toc06

SUPPLY VOLTAGE (V)

QUIESCENT SUPPLY CURRENT (μA)

2.0 3.02.5 4.5 5.03.5 4.0

160

180

200

260

280

120

140

220

240

300

100

1.5 5.5

MAX4995A

Typical Operating Characteristics

(VIN= +3.3V, CIN= 1µF, C

OUT

= 1µF, R

SETI

= 94.2kΩ, TA= +25°C, unless otherwise noted.)

CURRENT-LIMIT RESPONSE (MAX4995A)

APPLIED AT OUTPUT

10

s/div

CURRENT-LIMIT RESPONSE

4ms/div

MAX4995A toc03

SUDDEN SHORT

MAX4995A toc05

R

= 8Ω

LOAD

V

OUT

(2V/div)

I

OUT

(10A/div)

V

OUT

(2V/div)

I

OUT

(100mA/div)

CURRENT-LIMIT RESPONSE (MAX4995AF)

APPLIED AT OUTPUT

s/div

10

MAX4995A toc04

SUDDEN SHORT

V

OUT

(2V/div)

I

OUT

(10A/div)