1058 APPLICATION NOTE Only One Name Means ProTek’Tion™ Protecting LVDS Interfaces By: Sudesh Nayak Low-Voltage Differential Signaling or LVDS is a technology used in a variety of high-speed data transmission applications such as switches, set-top boxes and flat panel displays. In the simplest form, an LVDS interface, as defined by IEEE 1596.3 and ANSI/TIA/EIA-644, is a driver that transmits the signal over a trace or a cable to a receiver. If not protected properly, electrostatic discharge can damage the driver and receiver. In addition, the typical data transmission rate of LVDS is typically 500Mbps up to a theoretical maximum of 1.9Gbps. High data transmission rate applications require protection devices that can provide adequate protection while maintaining signal integrity. ProTek Devices SRV05-4LC is a 5 Volt, transient voltage suppression device that provides up to four channels of protection. The SRV05-4LC has a significantly low device capacitance (0.7pF typical) and break down voltage. These features make it an ideal device to protect LVDS Interfaces. LVDS calls for a protection device with low clamping voltage owing to its characteristic of low voltage operation. LVDS IEEE 1596.3 and ANSI/TIA/EIA-644 standard supports a maximum data rate of 655Mbps, which requires a protection device with a very low device capacitance to avoid loading or TABLE 1: ELECTRICAL CHARACTERISTICS PER LINE @ 25°C Unless Otherwise Specified PART NUMBER RATED STAND-OFF VOLTAGE MINIMUM BREAKDOWN VOLTAGE MAXIMUM CLAMPING VOLTAGE MAXIMUM LEAKAGE CURRENT TYPICAL CAPACITANCE I/O TO I/O MAXIMUM CAPACITANCE I/O to GND VWM VOLTS @ 1mA V(BR) VOLTS @ IP = 5A VC VOLTS @V WM ID µA @0V, 1MHz CJ(SD) pF @0V, 1MHz C J(SD) pF 5.0 6.0 15.0 5 0.7 1.4 SRV05-4LC signal distortion. Table 1 shows the electrical characteristics for the SRV05-4LC. The figure below shows two SRV05-4LC devices which protect both sides of the LVDS transmission system. The SRV05-4LC is connected a in line to line configuration where it protects a differential data line and also in a line to ground configuration showing a single ended. Driver B Driver Receiver A’ A B’ SRV05-4LC SRV05-4LC A A’ B B’ Receiver When operated in a differential mode (I/O to I/O) configuration, the SRV05-4LC has a typical device capacitance of 0.7pF. In a common mode configuration (I/O to ground), the capacitance rises to 1.4pF. In either case, the SRV05-4LC can handle up to 1Gbps data rate without any observable depreciation in signal integrity. The SRV05-4LC is qualified to meet and exceed the IEC 61000-4-2(Level 4 (ESD): ±8kV contact and ±15kV air) standard. It is also compatible with IEC 61000-4-4(EFT: 40A, 5/50ns) and IEC 61000-4-5(Surge: 24A,8/20µs – Level 2 and Level 3) standards. 1058.R0 11/13 Page 1 www.protekdevices.com 1058 APPLICATION NOTE Only One Name Means ProTek’Tion™ COMPANY INFORMATION COMPANY PROFILE In business more than 20 years, ProTek Devices™ is a privately held semiconductor company. The company offers a product line of overvoltage protection and overcurrent protection components. These include transient voltage suppressor array (TVS arrays) avalanche breakdown diode, steering diode TVS array and electronics SMD chip fuses. These components deliver circuit protection in electronic systems from numerous overvoltage and overcurrent events. They include lightning; electrostatic discharge (ESD); nuclear electromagnetic pulses (NEMP); inductive switching; and electromagnetic interference (EMI) / radio frequency interference (RFI). ProTek Devices also offers high performance interface and linear products. They include analog switches; multiplexers; LED drivers; LED wafer die for ESD protection; audio control ICs; RF and related high frequency products. CONTACT US Corporate Headquarters 2929 South Fair Lane Tempe, Arizona 85282 USA By Telephone General: 602-431-8101 Sales: & Marketing: 602-414-5109 Customer Service: 602-414-5114 Product Technical Support: 602-414-5107 By Fax General: 602-431-2288 By E-mail: Sales: [email protected] Customer Service: [email protected] Technical Support: [email protected] ProTek Devices (Asia Pacific) Pte. Ltd. 8 Ubi Road 2, #06-19 Zervex Singapore - 408538 Tel: +65-67488312 Fax: +65-67488313 Web www.protekdevices.com COPYRIGHT © ProTek Devices 2013 - This literature is subject to all applicable copyright laws and is not for resale in any manner. SPECIFICATIONS: ProTek reserves the right to change the electrical and or mechanical characteristics described herein without notice. DESIGN CHANGES: ProTek reserves the right to discontinue product lines without notice and that the final judgement concerning selection and specifications is the buyer’s and that in furnishing engineering and technical assistance. ProTek assumes no responsibility with respect to the selection or specifications of such products. ProTek makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ProTek assume any liability arising out of the application or use of any product or circuit and specifically disclaims any and all liability without limitation special, consequential or incidental damages. LIFE SUPPORT POLICY: ProTek Devices products are not authorized for use in life support systems without written consent from the factory. 1058.R0 11/13 Page 2 www.protekdevices.com