Abstract: A biasing network comprising two nominal type GZ 2422D transorbs, two resistors nominal 68 ohms and one resistor nominal 110 ohms replicated at each combined differential current driver of nominal type Am26L531 and differential receiver of nominal type Am26L532, as jointly form a transceiver, which are upon a two-wire differential signal communication path allows communication to transpire at a common-mode offset voltage, nominally .+-.8 volts, which is greater than the differential signal voltage that the receiver does elsewise communicate at, and which common-mode offset voltage is at a level which might but for the biasing network damage or destroy the driver.

Abstract: A method of and an apparatus for selectively isolating digital data bus drivers from digital data busses for fault recovery and diagnostic purposes. The digital data bus drivers may be either transistor-transistor logic (TTL) or emitter coupled logic (ECL). For TTL digital data bus drivers, the input voltage (V.sub.CC) is supplied via a switching power transistor. For ECL digital data bus drivers, the ground connection (V.sub.CC1) is made via a switching power transistor. In either case, the switching power transistor is turned on and off in response to one binary bit in an isolation register coupled to the power transistor via an open collector gate or electromechanical switch. By supplying the V.sub.CC (for TTL) or V.sub.