19-2926; Rev 0; 7/03
200mA/500mA Selectable
Current-Limit Switches
General Description
The MAX4772/MAX4773 switches feature selectable
internal current limiting to prevent damage to host
devices due to faulty load conditions. The
MAX4772/MAX4773 include a logic input to select a
guaranteed 200mA or 500mA current limit, making them
ideal for SDIO and other load-switching applications.
These analog switches have a low 0.2Ω on-resistance
and operate from a 2.0V to 4.5V input voltage range.
When the switch is on and a load is connected to the
port, a guaranteed blanking time of 14ms ensures that
the transient voltage settles down. If, after this blanking
time, the load current is greater than the current limit,
the MAX4772 switch is turned off and issues a
FLAG
to
the microprocessor. The switch can be turned on again
by cycling the power or the ON input.
The MAX4773 has an autoretry feature where the switch
turns off and issues a
FLAG
to the microprocessor after
the blanking time and then continuously checks to see if
the overload condition is present. The switch remains
on after the overload condition disappears and
FLAG
deasserts.
The MAX4772/MAX4773 are available in tiny space-sav-
ing 6-pin SOT23 and 6-pin TDFN (3mm x 3mm) pack-
ages.
o
o
o
o
o
o
o
o
o
o
o
o
o
o
Features
Guaranteed Current Limit: 200mA or 500mA
Thermal-Shutdown Protection
Reverse-Current Protection
0.2Ω On-Resistance (SEL = High)
14ms Guaranteed Blanking Time
FLAG
Function
Autoretry (MAX4773)
80µA Supply Current
6µA Latch-Off Current (MAX4772)
0.01µA Shutdown Current
2.0V to 4.5V Supply Range
Fast Current-Limit Response Time
Tiny SOT23 and TDFN Packages
UL Certification Pending
MAX4772/MAX4773
Ordering Information
PART
MAX4772EUT-T
MAX4772ETT*
MAX4773EUT-T
MAX4773ETT*
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
6 SOT23-6
6 TDFN-EP**
6 SOT23-6
6 TDFN-EP**
TOP
MARK
ABND
—
ABNE
—
Applications
SDIO
PDAs and Palmtop Devices
Cell Phones
GPS Systems
Hand-Held Devices
*Future
product—contact factory for availability.
**EP—Exposed
pad.
Selector Guide
PART
MAX4772EUK-T
MAX4772ETT
MAX4773EUK-T
MAX4773ETT
AUTORETRY
No
No
Yes
Yes
Typical Operating Circuit
2.0V TO 4.5V
Pin Configurations
TOP VIEW
IN
ON
µP
MAX4772
MAX4773
SEL
GND
FLAG
IN
1
GND
2
6
OUT
IN
1
OUT
2
SEL
3
6
ON
TO SDIO PORT
OUT
ON
3
MAX4772
MAX4773
5
SEL
4
FLAG
MAX4772
MAX4773
5
GND
4
FLAG
SOT23
TDFN
________________________________________________________________
Maxim Integrated Products
1
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.
200mA/500mA Selectable
Current-Limit Switches
MAX4772/MAX4773
ABSOLUTE MAXIMUM RATINGS
IN, ON,
FLAG,
SEL, OUT to GND.............................-0.3V to +6V
OUT Short Circuit to GND .................................Internally Limited
Continuous Power Dissipation (T
A
= +70°C)
6-Pin SOT23 (derate 8.7mW/°C above +70°C)............696mW
6-Pin TDFN (derate 24.4mW/°C above +70°C) .........1951mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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
= +2.0V to +4.5V, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at V
IN
= +3.3V, T
A
= +25°C.) (Note 1)
PARAMETER
Operating Voltage
Quiescent Current
Latch-Off Current (Note 2)
Shutdown Current
Forward-Current Limit
Reverse-Current Limit
ON Input Leakage
Shutdown Forward Leakage
Shutdown Reverse Leakage
SEL Pulldown Current
SEL Input Current
On-Resistance (Note 3)
ON, SEL Input Logic High
Voltage
ON, SEL Input Logic Low Voltage
FLAG
Output Logic Low Voltage
FLAG
Output High Leakage
Current
Thermal Shutdown
Thermal-Shutdown Hysteresis
DYNAMIC
Turn-On Time (Note 4)
Turn-Off Time (Note 4)
Blanking Time
t
BLANK
V
ON
from low to high, I
OUT
= 10mA,
C
L
= 0.1µF
V
ON
from high to low, I
OUT
= 10mA,
C
L
= 0.1µF
Overcurrent fault (Figures 4 and 5)
14
120
100
60
µs
ns
ms
R
ON
V
IH
V
IL
I
SINK
= 1mA
V
IN
= V
FLAG
= V
ON
= 4.5V
150
15
V
ON
= 0V, V
OUT
= 0V
V
ON
= 0V, V
IN
= 2V, V
OUT
= 4.5V
After power-up (V
IN
> 2V, 0V < V
SEL
< 0.5V)
Measured after first low-to-high transition
SEL = low, I
LOAD
= 100mA
SEL = high, I
LOAD
= 100mA
V
IN
= 2V to 3.6V
V
IN
> 3.6V
1.4
2
0.5
0.4
1
30
-1
0.45
0.18
SYMBOL
V
IN
I
Q
I
LATCH
I
SHDN
V
ON
= V
IN
, switch on
V
ON
= V
IN
, after an
overcurrent fault (MAX4772)
V
IN
= +3.3V
V
IN
= +3.3V
CONDITIONS
MIN
2.0
80
6
0.03
200
500
TYP
MAX
4.5
125
10
1
320
800
320
800
-1
0.01
+1
1
1
100
+1
0.9
0.36
UNITS
V
µA
µA
µA
mA
mA
µA
µA
µA
µA
µA
Ω
V
V
V
µA
°C
°C
V
ON
= 0V, SEL = low or floating
SEL = low, V
IN
= 3.3V, V
OUT
= GND
SEL = high, V
IN
= 3.3V, V
OUT
= GND
SEL = low
SEL = high
2
_______________________________________________________________________________________
200mA/500mA Selectable
Current-Limit Switches
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= +2.0V to +4.5V, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at V
IN
= +3.3V, T
A
= +25°C.) (Note 1)
PARAMETER
Short-Circuit Current-Limit
Response Time
Retry Time (Note 5)
t
RETRY
SYMBOL
CONDITIONS
V
ON
= V
IN
, short circuit applied to OUT
MAX4773 (Figure 4)
210
MIN
TYP
5
900
MAX
UNITS
µs
ms
MAX4772/MAX4773
Note 1:
All parts are 100% tested at +25°C. Electrical limits across the full temperature range are guaranteed by design and corre-
lation.
Note 2:
Latch-off current does not include the current flowing into
FLAG.
Note 3:
TDFN parts are guaranteed by design.
Note 4:
The on-time is defined as the time taken for the current through the switch to go from 0mA to full load. The off-time is defined
as the time taken for the current through the switch to go from full load to 0mA.
Note 5:
Retry time is typically 15 times the blanking time (typ).
Typical Operating Characteristics
(V
IN
= 3.3V, T
A
= +25°C, unless otherwise noted.)
QUIESCENT SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX4772 toc01
SUPPLY CURRENT vs. TEMPERATURE
V
ON
= V
IN
MAX4772 toc02
LATCH-OFF CURRENT
vs. TEMPERATURE
9
LATCH-OFF CURRENT (µA)
8
7
6
5
4
3
2
1
V
ON
= V
IN
MAX4772 toc03
160
140
SUPPLY CURRENT (µA)
120
100
80
60
40
V
ON
= V
IN
100
10
90
SUPPLY CURRENT (µA)
80
70
60
20
0
2.0
2.5
3.0
3.5
4.0
4.5
SUPPLY VOLTAGE (V)
50
-40
-15
10
35
60
85
TEMPERATURE (°C)
0
-40
-15
10
35
60
85
TEMPERATURE (°C)
SHUTDOWN SUPPLY CURRENT
vs. TEMPERATURE
MAX4772 toc04
SHUTDOWN LEAKAGE CURRENT
vs. TEMPERATURE
MAX4772 toc05
LATCH-OFF LEAKAGE CURRENT
vs. TEMPERATURE
LATCH-OFF LEAKAGE CURRENT (nA)
MAX4772 toc06
100
SHUTDOWN SUPPLY CURRENT (nA)
10
SHUTDOWN SUPPLY CURRENT (nA)
V
ON
= 0V, V
OUT
= 0V
100
10
1
0.1
0.01
0.001
10
1
1
0.1
0.1
0.01
0.01
0.001
-40
-15
10
35
60
85
TEMPERATURE (°C)
0.001
-40
-15
10
35
60
85
TEMPERATURE (°C)
0.0001
-40
-15
10
35
60
85
TEMPERATURE (°C)
________________________________________________________________________________________ 3
200mA/500mA Selectable
Current-Limit Switches
MAX4772/MAX4773
Typical Operating Characteristics (continued)
(V
IN
= 3.3V, T
A
= +25°C, unless otherwise noted.)
SHUTDOWN REVERSE LEAKAGE CURRENT
vs. TEMPERATURE
MAX4772 toc07
NORMALIZED ON-RESISTANCE
vs. TEMPERATURE
MAX4772 toc08
OUTPUT CURRENT
vs. OUTPUT VOLTAGE
900
800
OUTPUT CURRENT (mA)
700
600
500
400
300
200
V
SEL
= GND
V
SEL
= V
IN
MAX4772 toc09
10
SHUTDOWN LEAKAGE CURRENT (nA)
V
ON
= 0V, V
OUT
= 4.5V
1.4
1.2
NORMALIZED R
ON
(Ω)
1.0
0.8
0.6
0.4
0.2
0
1000
1
0.1
0.01
0.001
100
0
-40
-15
10
35
60
85
0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0 3.3
V
IN
- V
OUT
(V)
TEMPERATURE (°C)
0.0001
-40
-15
10
35
60
85
TEMPERATURE (°C)
FORWARD CURRENT LIMIT
vs. SUPPLY VOLTAGE
MAX4772 toc10
SWITCH TURN-ON/OFF TIMES
vs. TEMPERATURE
MAX4772 toc11
650
FORWARD CURRENT LIMIT (mA)
600
550
500
450
400
350
300
250
200
OUT = GND
I
LOAD
= 10mA
ON
SEL = HIGH
10
FLAG-BLANKING TIMEOUT (ms)
45
40
35
30
25
20
TURN-ON/OFF TIMES (µs)
1
0.1
OFF
SEL = LOW
0.01
2.0
2.5
3.0
3.5
4.0
4.5
-40
-15
10
35
60
85
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
-40
-15
10
35
60
85
TEMPERATURE (°C)
CURRENT-LIMIT RESPONSE
MAX4772/3 toc13
CURRENT-LIMIT RESPONSE
MAX4772/3 toc14
CURRENT-LIMIT RESPONSE
(OUT SHORTED TO GND)
MAX4772/3 toc15
3.3V
3V
V
IN
2V/div
V
ON
2V/div
0V
0V
I
OUT
200mA/div
V
IN
= 3.3V C
OUT
= 1µF
C
IN
= 1µF V
SEL
= 3.3V
40µs/div
0V
V
IN
= V
ON
C
OUT
= 1µF
C
IN
= 1µF V
SEL
= 3.3V
40µs/div
I
OUT
200mA/div
C
IN
= 1µF
C
OUT
= 1µF
0V
4µs/div
I
OUT
5A/div
3V
V
IN
= V
ON
1V/div
V
IN
2V/div
0V
3.3V
V
OUT
2V/div
0V
3V
0V
0V
4
_______________________________________________________________________________________
MAX4772 toc12
700
FLAG-BLANKING TIMEOUT
vs. TEMPERATURE
50
100
200mA/500mA Selectable
Current-Limit Switches
Typical Operating Characteristics (continued)
(V
IN
= 3.3V, T
A
= +25°C, unless otherwise noted.)
MAX4772/MAX4773
REVERSE CURRENT LIMIT
MAX4772/3 toc16
SWITCH TURN-ON TIME RESPONSE
MAX4772/3 toc17
3V
0V
3V
V
IN
2V/div
V
OUT
2V/div
3.3V
V
ON
1V/div
0V
0V
0V
C
IN
= 1µF
C
OUT
= 1µF
V
SEL
= 3.3V
200µs/div
I
OUT
1A/div
0V
I
OUT
10mA/div
20µs/div
SWITCH TURN-OFF TIME RESPONSE
MAX4772/3 toc18
FLAG-BLANKING RESPONSE
(OVERLOAD CONDITION)
MAX4772/3 toc19
3.3V
V
ON
1V/div
3.3V
V
IN
2V/div
0V
3.3V
V
OUT
2V/div
0V
I
OUT
10mA/div
0V
3.3V
0V
V
FLAG
2V/div
V
SEL
= V
IN
= 3.3V
C
IN
= 1µF
I
OUT
C
OUT
= 1µF
500mA/div
10ms/div
0V
0V
40ns/div
Pin Description
PIN
SOT23
1
2
3
TDFN
1
5
6
NAME
IN
GND
ON
FLAG
FUNCTION
Input. Bypass with a 0.1µF ceramic capacitor to ground.
Ground
Active-High Switch-On Input. A logic high turns the switch on.
Fault Output. This open-drain output goes low when the device stays in forward or reverse current limit
for more than the blanking time period.
FLAG
is high impedance when a fault is not present or when
ON is low.
Current-Limit Threshold Selection. Connect to logic-low level or leave floating to select 200mA current-
limit threshold. Connect to logic-high level to select 500mA current-limit threshold.
Switch Output. Bypass with a 0.1µF ceramic capacitor to ground.
4
4
5
6
3
2
SEL
OUT
_______________________________________________________________________________________
5
51mcu
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