Implementation of a 16 to 16 switching element for ATM exchanges

The authors describe the implementation of an asynchronous transfer mode (ATM) switching element with 16 inlets and 16 outlets at 600 Mb/s each. The single board switching element is used as a basic switching block in a connection-oriented ATM switching network. The design of the switching element was carried out by using advanced BiCMOS technologies. It is shown how the functional scheme is translated into a feasible chip partitioning and which design options were taken. In particular, the design of the cell switching facility and the queueing memory is treated in detail. A comparison between memory pooling or individual output queues is presented. By making the choice of the latter solution, the development schedule could be kept very tight. Second, the testability of the chips remains good despite the high gate complexity