SCAN921821 Datasheet | National Semiconductor

November 2004 .. - Dual 18-Bit Serializer with Pre-emphasis, IEEE 1149.1 (JTAG), and At-Speed BIST SCAN921821 Dual 18-Bit Serializer with Pre-emphasis, IEEE 1149.1 (JTAG), and At-Speed BIST General Description The SCAN921821 is a dual channel 18-bit serializer featuring signal conditioning, boundary SCAN, and at-speed BIST. Each serializer block transforms an 18-bit parallel LVCMOS/ LVTTL data bus into a single Bus LVDS data stream with embedded clock. This single serial data stream with embedded clock simplifies PCB design and reduces PCB cost by narrowing data paths that in turn reduce PCB size and layers. The single serial data stream also reduces cable size, the number of connectors, and eliminates clock-to-data and data-to-data skew. Each channel also has an 8-level selectable pre-emphasis feature that significantly extends performance over lossy interconnect. Each channel also has its own powerdown pin that saves power by reducing supply current when the channel is not being used. The SCAN921821 also incorporates advanced testability Features including IEEE 1149.1 and at-speed BIST PRBS pattern generation to facilitate verification of board and link integrity Features n 15-66 MHz Dual 18:1 Serializer with 2.376 Gbps total throughput n 8-level selectable pre-emphasis on each channel drives lossy cables and backplanes n > 15k V HBM ESD protection on Bus LVDS I/O pins n Robust BLVDS serial data transmission with embedded clock for exceptional noise immunity and low EMI n Power saving control pin for each channel n IEEE 1149.1 "JTAG" pliant n At-Speed BIST - PRBS generation n No external coding required n Internal PLL, no external PLL ponents required n Single +3.3V power supply n Low power: 260 m W (typ) per channel at 66 MHz with PRBS-15 pattern n Single 3.3 V supply n Fabricated with advanced CMOS process technology n Industrial - 40 to +85˚C temperature range n pact 100-ball FBGA package Block Diagram © 2004...