Device Offers Low Capacitance for HDMI Enabled Products

External video and data ports in computing devices and displays are often exposed to high voltages discharged from the human body through static buildup or from plugging in “hot” cables. Sensitive CMOS ICs driving or receiving signals through external interfaces such as high definition multimedia interface, digital visual interface, Ethernet, universal VGA/SVGA, and S-Video can easily be damaged or destroyed from such high energy surges.

Protecting external ports in these systems can be a challenge, as protection devices not only must withstand repeated voltage strikes but also exhibit low capacitance and leakage current to maintain signal integrity at high speeds. Clamping voltages must also be low enough to prevent latch-up and cumulative degradation to protected circuits.

The RClamp0544M is an array of transient voltage suppressor (TVS) diodes that protects sensitive ICs by delivering IEC-standard electro static discharge (ESD), electrical fast transient (EFT) and cable discharge events (CDE) protection on up to four high-speed data lines and one power supply rail (Vcc).
The device is a member of Semtech’s RailClamp® family of low capacitance protection devices and is based on proprietary process technology that delivers a capacitance of only 0.3pF for zero signal attenuation on data lines operating at 2Ghz or higher.

The layout of the device has also been optimized for HDMI/DVI designs, with all of the data lines entering on the same side of the package so that data signals flow straight through the device, eliminating bending or routing that can cause changes in impedance and impact signal quality.
The device is housed in a 3 mm x 5 mm MSOP-10L package that is RoHS/WEEE compliant. The package offers 0.5mm pitch between the signal line pair, which allows the signal lines to be tightly coupled and results in good common mode noise rejection.

“The RClamp0544M has been selected for the reference designs of three leading HDTV processor manufacturers, which is testimony to the industry’s need for the low capacitance, good protection and flow-through layout delivered by the device,” said Tom Dugan, Semtech's Director of Protection Products. “Semtech innovation has allowed us to reset the industry’s expectations for capacitance, and you can expect more on this front in the future as we strive to help customers protect ever faster data lines.”

The RClamp0544M is available immediately in production quantities and is priced at $0.52 each in 1,000-piece lots. Order code is RClamp0544M.TBT. Semtech offers comprehensive design assistance, including field- and factory-based support. Data sheets, volume pricing, and delivery quotes, as well as evaluation kits and samples, are available by contacting salesinfo@semtech.com.