Triple Skew-Compensating Video Delay Line with Analog and Digital Control Data Sheet AD8120 FEATURES GENERAL DESCRIPTION Corrects for unshielded twisted pair (UTP) cable skew The AD8120 is a triple broadband skew-compensating delay line Delay of up to 50 ns per channel that corrects for time mismatch between video signals incurred High speed by transmission in unshielded twisted pairs of Category 5 and 200 MHz BW V = 1.4 V p-p and 0 ns delay OUT Category 6 type cables. Skew between the individual pairs exists 150 MHz BW V = 1.4 V p-p and 50 ns delay OUT in most types of multipair UTP cables due to the different twist Excellent channel-to-channel matching rates that are used for each pair to minimize crosstalk between 30 mV offset matching RTI pairs. For this reason, some pairs are longer than others, and in 0.8% gain matching long cables, the difference in propagation time between two pairs Low output offset can be well into the tens of nanoseconds. 30 mV RTI The AD8120 contains three delay paths that provide broadband No external circuitry required to correct for offsets delays up to 50 ns, in 0.8 ns increments, using 64 digital control Independent red, green, and blue delay controls steps or analog control adjustment. The delay technique used in Drives 4 double-terminated video loads the AD8120 minimizes noise and offset at the outputs. Digital and analog delay control The bandwidth of the AD8120 ranges from 150 MHz to 200 MHz, 6-bit SPI bus 2 depending on the delay setting. This wide bandwidth makes the I C bus AD8120 ideal for use in applications that receive high resolution Analog voltage control video over UTP cables. Fixed gain of 2 Low noise The logic circuitry of the AD8120 provides individual delay con- High differential input impedance: 500 k trols for each channel. The delay times are set independently 2 32-lead, 5 mm 5 mm LFCSP using a standard 4-wire SPI bus or a standard I C bus, or by applying analog control voltages to the V , V , and V pins. CR CG CB APPLICATIONS Analog control offers a simple solution for systems that do not Keyboard-video-mouse (KVM) have digital control available. Digital signage The AD8120 is designed to be used with the AD8123 triple RGB video over UTP cable UTP equalizer in video over UTP applications, but it can Professional video projection and distribution also be used in other applications where similar controllable HD video broadband delays are required. Security video General broadband delay lines The AD8120 is available in a 5 mm 5 mm, 32-lead LFCSP and is rated to operate over the industrial temperature range of 40C to +85C. FUNCTIONAL BLOCK DIAGRAM R d G d B d Figure 1. Rev. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 20092012 Analog Devices, Inc. All rights reserved. 07839-001AD8120 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Typical Performance Characteristics ..............................................7 Applications ....................................................................................... 1 Theory of Operation .........................................................................9 General Description ......................................................................... 1 Controlling the Delay ...................................................................9 Functional Block Diagram .............................................................. 1 Setting the Delay ............................................................................9 Revision History ............................................................................... 2 Analog Control ........................................................................... 10 Specifications ..................................................................................... 3 Digital Control ............................................................................ 10 Absolute Maximum Ratings ............................................................ 5 Applications Information .............................................................. 14 Thermal Resistance ...................................................................... 5 Typical Application Circuit for the AD8123 and AD8120 ... 14 Maximum Power Dissipation ..................................................... 5 Outline Dimensions ....................................................................... 16 ESD Caution .................................................................................. 5 Ordering Guide .......................................................................... 16 Pin Configuration and Function Descriptions ............................. 6 REVISION HISTORY 5/12Rev. 0 to Rev. A Changes to Table 1 ............................................................................. 4 Added Power Down Section .......................................................... 10 Updated Outline Dimensions ........................................................ 16 7/09Revision 0: Initial Version Rev. A Page 2 of 16