Abstract: A high reliability, high voltage electronically controllable switch is created from a combination of relays of different types, with different characteristics, such as an electromechanical relay and an optoelectronic relay. The relays are closed and/or opened in accordance with a sequence that avoids actuating an electromechanical relay of such a compound switch to close or open under conditions that degrade the operating life of the electromechanical relay, even if the compound switch is hot switched under high voltage conditions. The switching sequence ends with the relays in a state that provides low on resistance, low crosstalk, low capacitance and/or low leakage. The switch can be relatively compact, enabling construction of an instrument serving as a switch matrix for an automatic test system.

Abstract: A high reliability, high voltage electronically controllable switch is created from a combination of relays of different types, with different characteristics, such as an electromechanical relay and an optoelectronic relay. The relays are closed and/or opened in accordance with a sequence that avoids actuating an electromechanical relay of such a compound switch to close or open under conditions that degrade the operating life of the electromechanical relay, even if the compound switch is hot switched under high voltage conditions. The switching sequence ends with the relays in a state that provides low on resistance, low crosstalk, low capacitance and/or low leakage. The switch can be relatively compact, enabling construction of an instrument serving as a switch matrix for an automatic test system.