19-4363; Rev 0; 11/08
50mA to 600mA Programmable
Current-Limit Switches
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/out-
put) 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 shut-
down 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.
♦
±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
Features
♦
50mA to 600mA Programmable Current Limit
MAX4995A/AF/AL/MAX4995B/MAX4995C
Pin Configurations
TOP VIEW
IN
10
N.C.
9
OUT
8
Applications
SDIO Ports
USB Ports
Notebook VGA Ports
GPS
Cell Phones
MP3 Players
UTCA/ATCA Platforms
Typical Operating Circuit appears at end of data sheet.
1.4mm x 1.8mm
UTQFN
* ( ) FOR THE MAX4995AL ONLY.
3
4
5
SETI
ON (ON)* GND
FLAG
2
IN
1
MAX4995A/MAX4995AF
MAX4995AL/MAX4995B
MAX4995C
7
OUT
6
N.C.
Pin Configurations continued at end of data sheet.
Ordering Information/Selector Guide
PART
MAX4995AAUK+T*
MAX4995AAVB+T
MAX4995AFAUK+T*
MAX4995AFAVB+T
MAX4995ALAUK+T*
PIN-
PACKAGE
6 SOT23
10 UTQFN
6 SOT23
10 UTQFN
6 SOT23
ON POLARITY
ActIve-High
Active-High
Active-High
Active-High
Active-Low
OVERCURRENT
RESPONSE
Autoretry
Autoretry
Autoretry
Autoretry
Autoretry
SHORT-CIRCUIT
RESPONSE
Normal
Normal
Fast
Fast
Normal
TOP MARK
+ACNZ
+AAM
+ACOE
+AAR
+ACDA
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.
________________________________________________________________
Maxim Integrated Products
1
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.
50mA to 600mA Programmable
Current-Limit Switches
MAX4995A/AF/AL/MAX4995B/MAX4995C
ABSOLUTE MAXIMUM RATINGS
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.
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.
ELECTRICAL CHARACTERISTICS
(V
IN
= +1.7V to +5.5V, R
SETI
= 94.3kΩ, C
IN
= 1µF, and T
A
= T
J
= -40°C to +125°C, unless otherwise noted. Typical values are at V
IN
= +3.3V,
T
A
= +25°C.)
PARAMETER
SUPPLY OPERATION
Operating Voltage
Quiescent Current
Latchoff Current
Shutdown Forward Current
Shutdown Reverse Current
INTERNAL FET
Switch-On Resistance
Normalized Current-Limit Accuracy
(R
SETI
+ 2.48) x I
LIM
Product
Reverse Blocking Current
Reverse Blocking Threshold
FLAG
Assertion Drop Voltage
Threshold
ON,
ON
INPUT
ON,
ON
Input Leakage
ON,
ON
Input Logic-High Voltage
ON,
ON
Input Logic-Low Voltage
FLAG
OUTPUT
FLAG
Output Logic-Low Voltage
FLAG
Output Leakage Current
I
SINK
= 1mA
V
IN
= V
FLAG
= 5.5V,
FLAG
deasserted
0.4
1
V
µA
I
LEAK
V
IH
V
IL
V
ON
, V
ON
= V
IN
or GND
-1
1.6
0.4
+1
µA
V
V
V
FA
R
ON
V
IN
= 3.3V, I
OUT
lower than I
LIM
I
LIM
= 50mA to 600mA, V
IN
- V
OUT
= 1V,
V
IN
= 3.3V (Note 3)
I
LIM
= 50mA to 600mA, V
IN
- V
OUT
= 1V,
V
IN
= 3.3V
V
OUT
> V
IN
+ 300mV after reverse-current-
limit shutdown
V
OUT
= V
IN
+ 300mV, OUT falling until switch
turns on
Increase (V
IN
- V
OUT
) drop until
FLAG
asserts, I
OUT
limiting, V
IN
= 3.3V
35
110
650
0.9
26138
130
1
29042
350
1.1
31946
10
210
mΩ
—
V
µA
mV
mV
V
IN
I
Q
I
LATCH
I
SHDN
I
RSHDN
I
OUT
= 0, switch on, V
IN
= 3.3V
V
IN
= 3.3V, I
OUT
= 0 after an overcurrent
fault (MAX4995B)
V
ON
= 0, V
ON
= V
IN
, V
IN
= 5.5V, V
OUT
= 0
V
ON
= 0, V
ON
= V
IN
, V
IN
= 1.7V,
V
OUT
= 5.5V (current into OUT)
1.7
170
8
0.01
0.01
5.5
300
15
5
1
V
µA
µA
µA
µA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
2
_______________________________________________________________________________________
50mA to 600mA Programmable
Current-Limit Switches
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= +1.7V to +5.5V, R
SETI
= 94.3kΩ, C
IN
= 1µF, and T
A
= T
J
= -40°C to +125°C, unless otherwise noted. Typical values are at V
IN
= +3.3V,
T
A
= +25°C.)
PARAMETER
DYNAMIC
Turn-On Time
Turn-Off Time
t
SS
t
OFF
V
IN
= 3.3V, C
OUT
= 1µF, R
L
= 20Ω, Figure 1,
(Note 4)
Switch from on to off, V
IN
= 3.3V, C
OUT
= 1µF,
R
L
= 20Ω, Figure 1 (Note 4)
V
IN
= 3.3V, R
SETI
=
578kΩ, output high
and then short-circuit
applied
(Note 5)
MAX4995A/MAX4995AF/MAX4995AL (Note 5)
MAX4995A/AL/B/C
MAX4995AF
10
320
+150
15
120
120
5
µs
1.5
16.3
22.6
723.2
ms
ms
°C
°C
µs
µs
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX4995A/AF/AL/MAX4995B/MAX4995C
Current-Limit Reaction Time
t
LIM
Blanking Time
Retry Time
THERMAL PROTECTION
Thermal Shutdown
Thermal-Shutdown Hysteresis
t
BLANK
t
RETRY
Note 3:
I
LIM
is forward current limit.
I
LIM
(mA)
=
29042(V)
R
SETI
(k
Ω
)
+
2.48 (k
Ω
)
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
t
RETRY
t
BLANK
is a constant value of 32. See Figures 2 and 3.
t
SS
90%
V
OUT
10%
t
OFF
10%
90%
Figure 1. Timing Diagram for Measuring Turn-On Time (t
SS
) and Turn-Off Time (t
OFF
).
_______________________________________________________________________________________
3
50mA to 600mA Programmable
Current-Limit Switches
MAX4995A/AF/AL/MAX4995B/MAX4995C
Typical Operating Characteristics
(V
IN
= +3.3V, C
IN
= 1µF, C
OUT
= 1µF, R
SETI
= 94.2kΩ, T
A
= +25°C, unless otherwise noted.)
CURRENT LIMIT
vs. SUPPLY VOLTAGE
MAX4995A toc01
NORMALIZED CURRENT LIMIT
vs. TEMPERATURE
MAX4995AL
1.075
NORMALIZED CURRENT LIMIT
1.050
1.025
1.000
0.975
0.950
0.925
MAX4995A toc02
315
MAX4995AL
310
CURRENT LIMIT (mA)
305
300
295
290
285
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
1.100
0.900
5.5
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
CURRENT-LIMIT RESPONSE (MAX4995A)
MAX4995A toc03
CURRENT-LIMIT RESPONSE (MAX4995AF)
MAX4995A toc04
SUDDEN SHORT
APPLIED AT OUTPUT
SUDDEN SHORT
APPLIED AT OUTPUT
V
OUT
(2V/div)
V
OUT
(2V/div)
I
OUT
(10A/div)
I
OUT
(10A/div)
10μs/div
10μs/div
CURRENT-LIMIT RESPONSE
MAX4995A toc05
QUIESCENT SUPPLY CURRENT
vs. SUPPLY VOLTAGE
280
260
240
220
200
180
160
140
120
MAX4995A
MAX4995A toc06
300
QUIESCENT SUPPLY CURRENT (μA)
R
LOAD
= 8Ω
V
OUT
(2V/div)
I
OUT
(100mA/div)
4ms/div
100
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
4
_______________________________________________________________________________________
50mA to 600mA Programmable
Current-Limit Switches
MAX4995A/AF/AL/MAX4995B/MAX4995C
Typical Operating Characteristics (continued)
(V
IN
= +3.3V, C
IN
= 1µF, C
OUT
= 1µF, R
SETI
= 94.2kΩ, T
A
= +25°C, unless otherwise noted.)
QUIESCENT SUPPLY LIMIT
vs. TEMPERATURE
MAX4995A toc07
SHUTDOWN SUPPLY CURRENT
vs. TEMPERATURE
MAX4995A toc08
SHUTDOWN FORWARD CURRENT
vs. TEMPERATURE
MAX4995C
SHUTDOWN FORWARD CURRENT (nA)
70
60
50
40
30
20
10
0
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
V
IN
= 1.7V
V
IN
= 5V
MAX4995A toc09
260
250
QUIESCENT SUPPLY CURRENT (μA)
240
230
220
210
200
190
180
170
160
150
140
2.50
SHUTDOWN SUPPLY CURRENT (μA)
2.25
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
0
V
IN
= 3.3V
V
IN
= 5V
MAX4995AL
80
V
IN
= 5V
V
IN
= 3.3V
MAX4995AL
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
SHUTDOWN REVERSE CURRENT
vs. TEMPERATURE
MAX4995A toc10
LATCHOFF CURRENT
vs. TEMPERATURE
MAX4995A toc11
NORMALIZED ON-RESISTANCE
vs. SUPPLY VOLTAGE
1.035
1.030
1.025
1.020
1.015
1.010
1.005
1.000
0.995
0.990
0.985
0.980
MAX4995C
I
OUT
< I
LIM
MAX4995A toc12
225
SHUTDOWN REVERSE CURRENT (nA)
200
175
150
125
100
75
50
25
0
V
IN
= 1.7V
V
IN
= 5V
MAX4995C
V
OUT
= 5.5V
20
MAX4995B
18
LATCHOFF CURRENT (μA)
16
14
12
10
8
6
V
IN
= 3.3V
V
IN
= 5V
1.040
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
NORMALIZED ON-RESISTANCE
1.7
2.2
2.7
3.2
3.7
4.2
4.7
5.2
SUPPLY VOLTAGE (V)
NORMALIZED ON-RESISTANCE
vs. TEMPERATURE
MAX4995A toc13
SWITCH TURN-ON TIME
vs. TEMPERATURE
MAX4995A toc14
SWITCH TURN-OFF TIME
vs. TEMPERATURE
1.5
SWITCH TURN-OFF TIME (ms)
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
V
IN
= 3.3V
V
IN
= 5V
MAX4995C
I
LOAD
= 10mA
MAX4995A toc15
1.5
1.4
NORMALIZED ON-RESISTANCE
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
MAX4995C
V
IN
= 3.3V
180
170
SWITCH TURN-ON TIME (μs)
160
150
140
130
120
110
100
V
IN
= 3.3V
V
IN
= 5V
MAX4995C
I
LOAD
= 10mA
1.6
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
-40 -25 -10 5 20 35 50 65 80 95 110 125
TEMPERATURE (°C)
_______________________________________________________________________________________
5
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