The DS26503 is a building-integrated timing-supply (BITS) clock-recovery element. It also functions as a basic T1/E1 transceiver. The receiver portion can recover a clock from T1, E1, and 6312kHz synchronization timing interfaces. In T1 and E1 modes, the Synchronization Status Message (SSM) can also be recovered. The transmit portion can directly interface to T1 or E1 interfaces as well as source the SSM in T1 and E1 modes. The DS26503 can translate between any of the supported inbound synchronization clock rates to any supported outbound rate. A separate output is provided to source a 6312kHz clock. The device is controlled through a parallel, serial, or hardware controller port. Applications * Basic Transceiver * BITS Timing * Rate Conversion * G.703 2048kHz Synchronization Interface Compliant * G.703 6312kHz Japanese Synchronization Interface Compliant * Interfaces to Standard T1/J1 (1.544MHz) and E1 (2.048MHz) * Interface to CMI-Coded T1/J1 and E1 * Short- and Long-Haul Line Interface * Transmit and Receive T1 and E1 SSM Messages with Message Validation * T1/E1 Jitter Attenuator with Bypass Mode * Fully Independent Transmit and Receive Functionality * Internal Software-Selectable Receive- and Transmit-Side Termination for 75Ω/100Ω/110Ω/120Ω * Monitor Mode for Bridging Applications * Accepts 16.384MHz, 12.8MHz, 8.192MHz, 4.096MHz, 2.048MHz, or 1.544MHz Master Clock * 8-Bit Parallel Control Port, Multiplexed or Nonmultiplexed, Intel or Motorola * Serial (SPI) Control Port * Hardware Control Mode * Provides LOS, AIS, and LOF Indications Through Hardware Output Pins * Fast Transmitter-Output Disable Through Device Pin for Protection Switching * IEEE® 1149.1 JTAG Boundary Scan * 3.3V Supply with 5V-Tolerant Inputs and Outputs