Transceiver Contains SONET/E4 Line Interface

Operating at 139.264 Mb/s for E4 or 155.52 Mb/s for OC-3, STS-3 or STM-1 rates, the 78P2253 SONET/SDH/E4 transceiver can interface to 75 ohm coaxial cable using CMI coding or a fiber-optic module via a serial PECL interface. Interfacing to a digital framer or multiplexer circuit is done via a serial PECL or parallel four- or eight-bit CMOS interface. The device is intended for WAN/ATM transmission, DSLAMs, digital cross connects, add/drop multiplexers, and digital loop carrier (DLC) equipment that are low power, small form factor, and high performance. The 78P2253 includes a PLL to multiply the 19.44 MHz for SONET mode or 17.283 MHz for E4 mode reference clock to the transmission frequency. The receiver performs adaptive equalization for accurate clock and data recovery. Analog and digital loopback modes aid system diagnostics. In BiCMOS, the device operates from 3.3V or 5V supplies. Price is $35 each/10,000.