Active bipolar transistor solid-state crosspoints

The new principle of an active crosspoint for telecommunications traffic exchanges is explained. Its basic difference concerns the application of device gain to obtain more favorable on-state specifications. The realization of this principle has resulted in a stable circuit which is insensitive to transients and temperature variations. This circuit also provides good off-state specifications and broad-band frequency performance. Finally, the concept is such that large-scale integration (LSI) by means of conventional bipolar technology allows the fabrication of large and low-cost crosspoint arrays.