19-1518; Rev 2; 9/01
USB Current-Limited Switches
with Fault Blanking
General Description
The MAX1693/(MAX1693H)/MAX1694 are current-limit-
ed, 60mΩ switches with built-in fault blanking. Their
accurate preset current limit of 0.7A to 1.0A makes them
ideally suited for USB applications. Their low quiescent
supply current (14µA) and shutdown current (1µA) con-
serve battery power in portable applications. The
MAX1693/(MAX1693H)/MAX1694 operate with inputs
from 2.7V to 5.5V, making them ideal for both 3V and 5V
systems.
A fault signal notifies the microprocessor that the inter-
nal current limit has been reached. A 10ms fault-blank-
ing feature allows momentary faults (such as those
caused when hot-swapping into a capacitive load) to be
ignored, thus preventing false alarms to the host system.
This fault blanking also prevents a fault signal from
being issued when the device is powering up.
In the MAX1693/(MAX1693H), an output overcurrent
condition causes the switch to current limit at 0.7A to
1.0A and
FAULT
to go low after the 10ms blanking peri-
od. When the overcurrent condition is removed,
FAULT
returns to its high-impedance state. In the MAX1694,
any overcurrent longer than 10ms will latch the switch
open and set
FAULT
low. The latch is cleared by cycling
the
ON
input or by powering up the device again. This
feature saves power by preventing the device from ther-
mally cycling on and off in case of a persistent short-cir-
cuit condition.
The MAX1693/(MAX1693H)/MAX1694 have several
safety features to ensure that the USB port is protected.
Built-in thermal-overload protection limits power dissi-
pation and junction temperatures. All devices have
accurate internal current-limiting circuitry to protect the
input supply against overload. They are available in
space-saving 10-pin µMAX packages.
Features
o
Accurate Current Limit (0.7A min, 1.0A max)
o
Guaranteed 0.75A Short-Circuit Protection
o
10ms Internal Fault-Blanking Timeout
o
No Fault Signal During Power-Up
o
Latched
FAULT
Output Turns Off Power Switch
(MAX1694)
o
Thermal Shutdown Protection
o
2.7V to 5.5V Supply Range
o
14µA Supply Current
o
Small 10-Pin µMAX Package
o
UL Recognized–#E211935
MAX1693/(MAX1693H)/MAX1694
Applications
USB Ports and Hubs
Notebook Computers
Portable Equipment
Docking Stations
Hot Plug-In Power Supplies
Battery-Charger Circuits
Ordering Information
PART
MAX1693EUB
MAX1693HEUB
MAX1694EUB
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
10 µMAX
10 µMAX
10 µMAX
Pin Configuration
TOP VIEW
IN 1
OUT
IN
OUT
(ON) ON
2
3
4
5
10 OUT
9
IN
OUT
FAULT
GND
(ON)
OFF
ON
(OFF)
INPUT
2.7V TO 5.5V
Typical Operating Circuit
IN
OUT
OUTPUT
MAX1693
(MAX1693H)
MAX1694
FAULT
MAX1693
(MAX1693H)
MAX1694
8
7
6
ON (ON)
GND
µMAX
_______________________________________________________________
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.
USB Current-Limited Switches
with Fault Blanking
MAX1693/(MAX1693H)/MAX1694
ABSOLUTE MAXIMUM RATINGS
IN,
ON
(ON),
FAULT
to GND....................................-0.3V to +6V
OUT to GND ................................................-0.3V to (V
IN
+ 0.3V)
Maximum Continuous Switch Current .....1.2A (internally limited)
OUT Short Circuit to GND ..........................................Continuous
Continuous Power Dissipation (T
A
= +70°C)
10-Pin µMAX (derate 5.6mW/°C above +70°C) ............444mW
Operating Temperature Range
MAX1693EUB/MAX1693HEUB/
MAX1694EUB ..................................................-40°C to +85°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
= +5V,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
Operating Voltage
Quiescent Current
Off-Supply Current
Undervoltage Lockout
Off-Switch Leakage
UVLO
SYMBOL
V
IN
I
Q
V
ON
(ON)
= GND (V
IN
)
I
OUT
= 0
Timer not running
Timer running
2.0
0.01
CONDITIONS
MIN
2.7
14
35
0.001
1
2.6
2
µA
T
A
= 0°C to +85°C
V
IN
= 4.4V to 5.5V
V
IN
= 4.4V to 5.5V
V
IN
= 3V
700
72
850
500
60
15
90
125
150
1000
700
0.8
2
2.4
±1
0.4
1
7
10
1
80
3
6
165
200
20
13
mA
mA
V
V
µA
V
µA
ms
ms
µs
µs
°C
mΩ
TYP
MAX
5.5
25
UNITS
V
µA
µA
V
V
ON
(ON)
= V
IN
= V
OUT
= 5.5V (V
ON
= GND)
Rising edge, 100mV hysteresis
V
ON
(ON)
= V
IN
(GND)
V
IN
= 5.5V,
V
OUT
= GND
T
A
= +25°C
R
ON
I
LIMIT
I
SC
V
IL
V
IH
T
A
= +25°C
On-Resistance
Current Limit
Continuous Short-Circuit
Current Limit
ON
(ON) Input Logic Low Voltage
ON
(ON) Input Logic High
Voltage
ON
(ON) Input Leakage
FAULT
Output Logic Low
Voltage
FAULT
Output High Leakage
Current
Fault-Blanking Timeout Period
Start-Up Time
Switch Turn-On Time
Switch Turn-Off Time
Thermal Shutdown Threshold
T
A
= 0°C to +85°C
(Note 1)
OUT shorted to GND, MAX1693/(MAX1693H)
only (Note 2)
V
IN
= 2.7V to 5.5V
V
IN
= 2.7V to 3.6V
V
IN
= 3.7V to 5.5V
V
ON
(ON)
= V
IN
or GND
V
OL
I
SINK
= 1mA, V
IN
= 3V
V
IN
= V
FAULT
= 5.5V
t
FB
From overcurrent condition to
FAULT
assertion
V
IN
= 5V, C
OUT
= 150µF, R
L
= 15Ω,
from
ON
(ON) driven low (high) to 50% full V
OUT
t
ON
t
OFF
I
LOAD
= 400mA
I
LOAD
= 400mA
2
_______________________________________________________________________________________
USB Current-Limited Switches
with Fault Blanking
ELECTRICAL CHARACTERISTICS
(V
IN
= +5V,
T
A
= -40°C to +85°C,
unless otherwise noted.) (Note 3)
PARAMETER
Operating Voltage
Quiescent Current
Off-Supply Current
Undervoltage Lockout
Off-Switch Leakage
On-Resistance
Current Limit
Continuous Short-Circuit
Current Limit
ON
(ON) Input Logic Low Voltage
ON
(ON) Input Logic High
Voltage
ON
(ON) Input Leakage
FAULT
Output Logic Low
Voltage
FAULT
Output High Leakage
Current
Fault-Blanking Timeout Period
Switch Turn-On Time
Switch Turn-Off Time
t
FB
t
ON
t
OFF
V
OL
V
IL
V
IH
R
ON
I
LIMIT
UVLO
SYMBOL
V
IN
I
Q
V
ON
(ON)
= GND (GND), I
OUT
= 0, timer not
running
V
ON
(ON)
= V
IN
= V
OUT
= 5.5V (V
ON
= GND)
Rising edge, 100mV hysteresis
V
ON
(ON)
= V
IN
= 5.5V, V
OUT
= GND
(V
ON
= GND)
V
IN
= 4.4V to 5.5V
V
IN
= 3V
(Note 1)
OUT shorted to GND, MAX1693/(MAX1693H)
only (Note 2)
V
IN
= 3V to 5.5V
V
IN
= 3V to 3.6V
V
IN
= 3.7V to 5.5V
V
ON
(ON)
= V
IN
or GND
I
SINK
= 1mA, V
IN
= 3V
V
IN
= V
FAULT
= 5.5V
From overcurrent condition to
FAULT
assertion
I
LOAD
= 400mA
I
LOAD
= 400mA
1
6
2
2.4
±1
0.4
1
14
200
20
640
2.0
CONDITIONS
MIN
3
TYP
MAX
5.5
25
2
2.9
15
125
150
1060
750
0.8
UNITS
V
µA
µA
V
µA
mΩ
mA
mA
V
V
µA
V
µA
ms
µs
µs
MAX1693/(MAX1693H)/MAX1694
3
Note 1:
MAX1693/(MAX1693H)’s current limit is tested by forcing V
OUT
to 4.5V. The MAX1694’s current limit is tested by increasing
the output current until the switch is latched off.
Note 2:
This specification applies to the MAX1693/(MAX1693H) only. The MAX1694 latches the switch off under a sustained
(>10ms) short-circuit condition.
Note 3:
Specifications to -40°C are guaranteed by design, not production tested.
_______________________________________________________________________________________
USB Current-Limited Switches
with Fault Blanking
MAX1693/(MAX1693H)/MAX1694
Typical Operating Characteristics
(V
IN
= +5V, T
A
= +25°C, unless otherwise noted.)
QUIESCENT CURRENT vs. TEMPERATURE
MAX1693/4 toc02
QUIESCENT CURRENT vs. INPUT VOLTAGE
MAX1693/4 toc01
OFF-SUPPLY CURRENT
vs. TEMPERATURE
V
ON
(ON) = V
IN
(GND)
OFF-SUPPLY CURRENT (nA)
10
MAX1693/4 toc03
16
14
QUIESCENT CURRENT (µA)
12
10
8
6
4
2
0
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
V
ON (ON)
= GND (V
IN
)
I
OUT
= O
16
V
IN
= 5V
15
QUIESCENT CURRENT (µA)
14
13
12
11
10
9
-40
-20
0
20
40
60
80
V
IN
= 3V
100
1
0.1
0.01
100
-40
-20
TEMPERATURE (°C)
0
20
40
60
TEMPERATURE (°C)
80
100
OFF-SWITCH CURRENT vs. TEMPERATURE
V
0N (ON)
= V
IN
(GND)
OFF-SWITCH CURRENT (nA)
100
MAX1693/4 toc04
NORMALIZED ON-RESISTANCE
vs. TEMPERATURE
I
OUT
= 425mA
1.2
NORMALIZED R
ON
1.0
0.8
0.6
0.4
MAX1693/4 toc05
NORMALIZED OUTPUT CURRENT
vs. OUTPUT VOLTAGE
I
LIMIT
MAX1693/4 toc06
1000
1.4
1.2
NORMALIZED OUTPUT CURRENT
1.0
0.8
SHORT-CIRCUIT CURRENT
0.6
0.4
0.2
0
10
1
0.1
0.2
0.01
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
0
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
0
1
2
3
4
5
6
OUTPUT VOLTAGE (V)
TURN-ON TIME vs. TEMPERATURE
MAX1693/4 toc07
TURN-OFF TIME vs. TEMPERATURE
I
LOAD
= 425mA
V
IN
= 5V
MAX1693/4 toc08
160
I
LOAD
= 425mA
140
120
100
t
ON
(µs)
80
60
40
20
0
-40
-20
0
20
40
60
80
V
IN
= 5V
V
IN
= 3V
7
6
5
t
OFF
(µs)
4
3
2
1
0
V
IN
= 3V
100
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
TEMPERATURE (°C)
4
_______________________________________________________________________________________
USB Current-Limited Switches
with Fault Blanking
Typical Operating Characteristics (continued)
(V
IN
= +5V, T
A
= +25°C, unless otherwise noted.)
FAULT-BLANKING TIMEOUT
vs. TEMPERATURE
MAX1693/4 toc09
MAX1693/(MAX1693H)/MAX1694
MAX1693
CURRENT-LIMIT AND FAULT RESPONSE
MAX1693/4 toc10
MAX1693
CURRENT-LIMIT RESPONSE
1
MAX1693/4 toc11
12
FAULT-BLANKING TIMEOUT (ms)
10
8
6
1
2
2
3
4
2
0
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
I
OUT
= 850mA
V
IN
= 3V OR 5V
4
2ms/div
CH1 = V
IN
, 200mV/div, AC-COUPLED; CH2 = V
OUT
,
5V/div; CH3 = V
FAULT
, 5V/div; CH4 = I
OUT
, 500mA/div
3
4
10µs/div
CH1 = V
IN
, 200mV/div, AC-COUPLED; CH2 = V
OUT
,
5V/div; CH3 = V
FAULT
, 5V/div; CH4 = I
OUT
, 1A/div
MAX1693
SWITCH TURN-ON TIME
MAX1693/4 toc12
MAX1693
SWITCH TURN-OFF TIME
MAX1693/4 toc13
MAX1693
STARTUP TIME
(TYPICAL USB APPLICATION)
1
FULL-CURRENT LIMIT
CHARGES CAPACITOR
C
L
= 150µF
R
L
= 15Ω
RESISTOR
LOAD
CURRENT
MAX1693/4 toc14
1
2
1
2
2
3
3
3
FOLDBACK-
CURRENT LIMIT
4
20µs/div
CH1 = V
OUT
, 5V/div; CH2 = V
ON
, 5V/div;
CH3 = V
FAULT
, 5V/div; CH4 = I
OUT
, 200mA/div
4
4
1µs/div
CH1 = V
OUT
, 5V/div; CH2 = V
ON
, 5V/div;
CH3 = V
FAULT
, 5V/div; CH4 = I
OUT
, 200mA/div
1ms/div
CH1 = V
OUT
, 5V/div; CH2 = V
ON
, 5V/div;
CH3 = I
OUT
, 500mA/div; CH4 = V
FAULT
, 5V/div
_______________________________________________________________________________________
5
Embedded System
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