National Semiconductor LM3525 Technical data
LM3525
Single Port USB Power Switch and Over-Current
Protection
LM3525 Single Port USB Power Switch and Over-Current Protection
March 2005
General Description
The LM3525 provides Universal Serial Bus standard power
switch and over-current protection for all host port applications. The single port device is ideal for Notebook PC and
Handheld PC applications that supply power to one port.
A 1 ms delay on fault flag output prevents erroneous overcurrent reporting caused by inrush currents during the hotplug events.
The LM3525 accepts an input voltage between 2.7V and
5.5V allowing use as a device-based inrush current limiter
for 3.3V USB peripherals, as well as Root and Self-Powered
Hubs at 5.5V. The Enable input accepts both 3.3V and 5.0V
logic thresholds.
The small size, low R
LM3525 a good choice for root hubs as well as ganged
power control in space-critical self-powered hubs.
, and 1 ms fault flag delay make the
ON
Features
n Compatible with USB1.1 and USB 2.0
n 1 ms Fault Flag Delay During Hot-Plug Events
n Smooth Turn-On Eliminates Inrush Induced Voltage
Drop
n UL Recognized Component: REF # 205202
n 1A Nominal Short Circuit Output Current Protects
Notebook PC Power Supplies
n Thermal Shutdown Protects Device in Direct Short
Condition
n 500mA Minimum Continuous Load Current
n Small SO-8 Package Minimizes Board Space
n 2.7V to 5.5V Input Voltage Range
n Switch Resistance ≤ 120 mΩ Max. at V
n 1µA Max Standby Current
n 100 µA Max Operating Current
n Undervoltage Lockout (UVLO)
IN
=5V
Applications
n Universal Serial Bus (USB) Root Hubs including
Desktop and Notebook PC
n USB Monitor Hubs
n Other Self-Powered USB Hub Devices
n High Power USB Devices Requiring Inrush Limiting
n General Purpose High Side Switch Applications
Typical Operating Circuit and Connection Diagram
LM3525M-L
10105501
LM3525M-H
© 2005 National Semiconductor Corporation DS101055 www.national.com
10105502
10105531
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Ordering Information
LM3525
Part Number Enable, Delivery Option Package Type
LM3525M-H Active High Enable, 95 units per rail
LM3525M-L Active Low Enable, 95 units per rail
LM3525MX-H Active High Enable, 2500 units per reel
LM3525MX-L Active Low Enable, 2500 units per reel
SO-8,
NS Package
Number M08A
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LM3525
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage −0.3V to 6.0V
Output Voltage −0.3V to 6.0V
Voltage at All Other Pins −0.3V to 5.5V
Power Dissipation (T
(Note 2) 700 mW
(Note 2) 150˚C
T
JMAX
= 25˚C)
A
Operating Ratings
Supply Voltage Range 2.7 to 5.5V
Operating Ambient Range −40˚C to +85˚C
Operating Junction Temperature
Range −40˚C to +125˚C
Storage Temperature Range −65˚C to +150˚C
Lead Temperature
(Soldering, 5 seconds) 260˚C
ESD Rating (Note 3) 2 kV
DC Electrical Characteristics
Limits in standard typeface are for TJ= 25˚C, and limits in boldface type apply over the full operating temperature range. Unless otherwise specified: V
Symbol Parameter Conditions Min Typ Max Units
R
I
ON
OUT
On-Resistance
OUT pins continuous output
current
I
SC
I
LEAK
Short Circuit Output Current (Note 4) 0.5 1.0 1.5 A
OUT pins Output Leakage
Current
OC
R
FO
I
EN
V
IH
V
IL
V
UVLO
I
DDOFF
I
DDON
Th
THRESH
SD
Over-current Threshold 2.25 3.2 A
FLAG Output Resistance
EN/EN Leakage Current EN/EN = 0V or EN/EN = V
EN/EN Input Voltage (Note 5) 2.4 1.9 V
EN/EN Input Voltage (Note 5) 1.7 0.8 V
Under-Voltage Lockout VIN= Increasing
Supply Current Switch OFF 0.05 1 µA
Supply Current Switch ON 65 100 µA
Overtemperature Shutdown
Threshold (Note 4)
I
FH
Error Flag Leakage Current V
= 5.0V, EN = 0V (LM3525-L) or EN = VIN(LM3525-H).
IN
IN to Out pins
VIN=5V
= 2.7V
V
IN
EN=VIN(LM3525-L) or
EN = GND (LM3525-H),
= 10 mA, VIN=5V 6 25
I
FO
I
= 10 mA, VIN= 2.7V 8 40
FO
= Decreasing
V
IN
TJIncreasing
Decreasing
T
J
= 5V 0.1 1 µA
FLAG
80
120
120
160
0.5 A
0.15 10 µA
IN
−0.5 0.5 µA
1.9
1.8
135
125
mΩ
Ω
V
˚C
˚C
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