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PROTECTION PRODUCTS
RClamp0554S
Applications Information (continued)
helps to mitigate the effects of parasitic inductance in
the power supply connection. During an ESD event,
the current will be directed through the integrated TVS
diode to ground. The maximum voltage seen by the
protected IC due to this path will be the clamping
voltage of the device.
Universal Serial Bus ESD Protection
The RClamp0554S may also be used to protect the
USB ports on monitors, computers, peripherals or
portable systems. Each device will protect up to two
USB ports (Figure 4). When the voltage on the data
lines exceed the bus voltage (plus one diode drop), the
internal rectifiers are forward biased conducting the
transient current away from the protected controller
chip. The TVS diode directs the surge to ground. The
TVS diode also acts to suppress ESD strikes directly on
the voltage bus. Thus, both power and data pins are
protected with a single device.
Figure 4 - Dual USB Port Protection
RClamp0554S
