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EClamp2122S
USB Downstream Port Filter & TVS
For EMI Filtering and ESD Protection
PROTECTION PRODUCTS - EMIClamp
®
Description
Features
Circuit Diagram Pin Configuration
Revision 1/24/2011
Applications
Mechanical Characteristics
JEDEC SOT-23 6L package
Pb-Free, Halogen Free, RoHS/WEEE Compliant
Nominal Dimensions: 2.9 x 2.8mm
Molding compound flammability rating: UL 94V-0
Marking: Marking Code + Date Code
Packaging: Tape and Reel
(Top Side View)
The EClamp
®
2122S is combination EMI filter and line
termination device with integrated TVS diodes for use
on USB 2.0 interfaces. This device utilizes solid-state
silicon-avalanche technology for superior clamping
performance and DC electrical characteristics. They
have been optimized for
protection of USB inter-protection of USB inter-
protection of USB inter-protection of USB inter-
protection of USB inter-
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faces in cellular phones and other portable electron-
ics.
USB line termination is achieved with a series 22Ω
resistor on both the D+ and D- USB lines. These
resistors preserve signal integrity by matching the cable
impedance to that of the differential driver. The 15kΩ
pull-down resistors complete the termination circuit on
each line. They are required by the USB specification
to identify the line as a downstream connection. The
capacitors are used to bypass high frequency energy to
ground and for edge rate control of the USB signals.
Integrated TVS diodes provide ESD protection of both
(D+ & D-) data lines and the voltage bus (V
BUS
). The
TVS diodes provide effective suppression of ESD
voltages in excess of 25kV (air discharge) and 20kV
(contact discharge) per IEC 61000-4-2.
The EClamp2122S is in a 6-pin SOT-23 package. The
leads are finished with lead-free matte tin. It is suit-
able for use in USB hubs, computers, peripherals, and
portable devices
USB 1.1 Interfaces
USB Hubs
Printers
Monitors
Servers, Desktop, and Notebook computers
EMI/RFI filtering and line termination with inte-
grated ESD protection
ESD protection for USB power (V
BUS
) and data lines
(D+ & D-) to IIEC 61000-4-2 (ESD), ±25kV (air),
±20kV (contact)
Filtering and termination for two USB data lines
Series resistors for impedance matching
Integrated pull down resistors as required by the
USB specification for downstream ports
Low TVS operating voltage (5.25V)
Solid-state technology
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