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ltp2884fa
PRODUCT MANUAL LTP2884
Description
USB Isolator
The LT P 2884 is a complete USB isolator solution, ideal
for any application requiring ground isolation, protection
from large common mode voltage variations, or protection
from spikes and surges. Built with convenience in mind,
this robust isolator brings comprehensive protection to
a wide variety of applications without the need for any
configuration or additional software.
At the heart of the LT P 2884 is the LTM2884, an isolated
USB 2.0 compatible µModule
®
transceiver with isolated
power and automatic USB bus speed selection. Isolator
µModule technology uses coupled inductors and an iso
-
lated power transformer to provide 2500V
RMS
of isolation
between the upstream and downstream USB interface. All
accessible lines on the LT P 2884 carry additional surge
protection and ESD protection up to ±20kV. Uninterrupted
communication is guaranteed for common mode transients
greater than 30kV/µs.
The LT P 2884 is compatible with USB 2.0 full speed
(12Mbps) and low speed (1.5Mbps) operation. Automatic
L, LT, LTC, LTM, Linear Technology, µModule and the Linear logo are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
speed selection configures integrated pull-up resistors on
the upstream port to match those sensed on the down-
stream device
.
By default, downstream devices are powered
(up to 1W) by the upstream bus through an isolated DC/
DC converter. Optionally, a wall adapter can be used, in
-
creasing available power to downstream devices to 2.5W.
The LT P 2884 has additional features which help to ensure
reliable operation. Status LEDs indicate the presence of
auxiliary and USB bus power. Warning LEDs indicate
overcurrent on the upstream bus and undervoltage on
the downstream bus, making it clear when an application
requires auxiliary power. High retention USB connectors
protect against accidental unplugging during operation.
Design files for this circuit board are available at
http://www.linear.com/demo
Features
n
2.5kV
RMS
Rated Dielectric Isolation Voltage for One
Minute
n
USB 2.0 Full Speed and Low Speed Support
n
Bus Powered with Optional External Supply
n
Hot Plug Protection
n
No Drivers or Software Required
n
400V
RMS
Continuous Working Voltage
n
±20kV ESD Protection
n
High Common Mode Transient Immunity
n
Small Rugged Enclosure
n
LED Status and Warning Indicators
n
High Retention USB Connectors
