The DS26519 from Dallas Semiconductor reduces cost per port in channel service 
  units, data service units, multiplexers, switches, routers, channel banks, and 
  test equipment. This 16-port, T1/E1/J1 long- and short-haul transceiver doesn’t 
  need any mechanical relays for redundancy protection because it uses what Dallas 
  calls “hitless protection switching,” which presents high impedance 
  at transmit outputs and receive inputs whenever there’s no power.
Additionally, it offers software-selectable, internal receive- and transmit-side 
  termination for 75-Ω E1 coaxial, 100-Ω T1 twisted-pair, 110-Ω 
  J1 twisted-pair, or 120-Ω E1 twisted-pair applications. Performance monitoring 
  and diagnostics include a bit-error-rate tester; loss-of-signal indication; 
  analog, local, remote, and dual loopbacks; large error counters for BPV, CV, 
  CRC-6, CRC-4, and E-bit; in-band repeating-pattern generation/detection; and 
  JTAG. 
Housed in a 484-pin heat-slug ball-grid array (HSBGA) package, the DS26519 
  costs $69.96 in sample quantities. The eight-port DS26518 comes in a 256-pin 
  BGA and costs $40.60.
Maxim Integrated Products 
 www.maxim-ic.com