SC5826-2CS Semtech Corporation, SC5826-2CS Datasheet - Page 6

• Manufacturer Part Number: SC5826-2CS
• Description: HotSwitch USB Power Distribution Switch
• Manufacturer: Semtech Corporation

PRELIMINARY - February 18, 2000
© 2000 SEMTECH CORP.
Self-powered hub, indidual port power
management:
A self-powered hub must supply a continuous 500mA
of current to each downstream port. Since an internal
power supply is used to supply the power, self-powered
hubs are required to implement overcurrent protection
for safety. The self-powered hub must also have a
method to detect and report fault conditions to the USB
controller. The circuit below utilizes the SC5826 to pro-
vide individual port overcurrent protection & power
switching for maximum port protection. Under fault
conditions, the SC5826 provides the short-circuit cur-
rent limiting function and has a fault flag logic output for
notifying the hub controller. The USB hub can use the
Figure 1 - Self-powered hub with individual port power management
TYPICAL APPLICATIONS
HotSwitch™
USB Power Distribution Switch
SC5826 to remove power from the faulty port, allowing
the other ports to operate normally.
Since USB is a hot insertion and removal system, USB
ports are subject to electrostatic discharge (ESD). The
SRDA05-4 provides ESD protection on the down-
stream data and power lines. Each device will protect
two USB ports. With proper layout the port is hard-
ened to greater than 15kV, meeting the requirements
of IEC 1000-4-2. On the upstream port, the LCDA05
provides ESD protection to the above levels for one
line pair. The SC5203 (or SC5205) LDO regulator is
used to power the hub controller from the upstream
bus.
652 MITCHELL ROAD NEWBURY PARK CA 91320
SC5826
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