A LSI time switch for digital telephone switching

AN LSI TIME SWITCH for the digital telephone switching system,which includes an 11K static RAM and 600 gates of peripheral circuits, affording performance of greater than 20MHz maximum operating frequency and 600mW power consumption, will be described. The LSI was designed for the time switch memory in the speech path of the digital telephone switching system. The low power characteristic of the LSI has made it possible to cool the system without a fan. In using general-purpose ICs, about 50 ICs are needed and the power consumption may exceed 8W to achieve the required performance. This time switch LSI realizes an equivalent lattice size of 1024 x 1024 on a single chip, quadmple of the conventional time switch LSI.