Multiport Transceivers

TDK Semiconductor has introduced an expanded line of multiport interface transceiver ICs for E3, DS3 and STS-1 applications.

The devices operate with a 3.3 V supply. The 78P2242 (dual port), 78P2243 (triple port) and 78P2244 (quad port) are extensions of the 78P2241 single chip IC.

Each channel features a clock recovery and transmitter pulse shaping function for applications using 75 ohm coaxial cable at distances up to 330 m.

A new feature to the multiports is the input receiver MUX, which saves board space and component cost by replacing external switches.

The receivers from each device recover clock and data from a B3ZS or HDB3 coded AMI signal. The CDR (clock/data recovery) circuit can compensate for over 12 dB of cable and 6 dB of flat loss.

The transmitters in each device generate signals that meet the standard pulse shape requirements and a line build-out function controls the amplitude and pulse shape in DS3 mode.

The devices have selectable B3ZS/HDB3 ENDECs with receive line code violation detectors, loop-back modes, and the ability to receive DSX3 monitor signals.