General Description
The VSC8140 is a SONET/SDH compatible transceiver with integrated clock generator for use in SONET/SDH systems operating at a 2.48832Gb/s data rate. The internal clock generator uses a Phase-Locked Loop (PLL) to multiply either a 77.76MHz or 155.52MHz reference clock in order to provide the 2.48832GHz clock for internal logic and output retiming. The 16-bit parallel interface incorporates an on-board FIFO eliminating loop timing design issues by providing a flexible parallel timing architecture. In addition, the device provides both facility and equipment loopback modes and two loop timing modes. The VSC8140 operates using a 3.3V power supply, and is available in either a thermally-enhanced 128-PQFP or a thermally-enhanced 208-pin TBGA package.
   
Features
• 2.48832Gb/s 16-Bit Transceiver
• Targeted for SONET OC-48 / SDH STM-16
    Applications
• LVPECL Low-Speed Interface
• On-chip PLL-Based Clock Generator
• High-Speed Clock Output With Power-Down
    Option
• Supports Parity at the 16-Bit Parallel Transmit
    and Receive Interfaces
• Provides Equipment, Facilities and Split
    Loopback Modes as well as Loop Timing Modes
• Loss of Signal (LOS) Detect input
• Meets Bellcore Jitter Performance Specifications
• Single +3.3V Supply
• 2.25 Watts Typical Power Dissipation
• Packages: 128-pin PQFP or 208-pin TBGA