Low power CML IC crosspoint switch matrix for space division digital switching networks

Describes a crosspoint switch matrix which is constructed from CML gates for digitized video signals and p-n-p n-p-n transistor type holding circuits that hold the ON or OFF state of the CML gates. This holding circuit cuts off the power of the unselected crosspoints to reduce the total power dissipation of the switch matrix circuit. The CML IC crosspoint switch, with a 4×4 matrix size, is fabricated on a single chip. Dynamic test of the subsystem, in which fabricated switch matrices are connected in cascade stages, has indicated that it is applicable to high speed space division digital switching networks.