Science & Technology Corporation &commat; Unm

University of New Mexico

Gary K Maki

James E Murguia

Jody W Gambles

Kenneth J Hass

Shi Quan

Prakash R Bhatia

Kenneth Haas

Logic elements are provided that permit reductions in layout size and avoidance of hazards. Such logic elements may be included in libraries of logic cells. A logical function to be implemented by the logic element is decomposed about logical variables to identify factors corresponding to combinations of the logical variables and their complements. A pass transistor network is provided for implementing the pass network function in accordance with this decomposition. The pass transistor network includes ordered arrangements of pass transistors that correspond to the combinations of variables and complements resulting from the logical decomposition. The logic elements may act as selection circuits and be integrated with memory and buffer elements.

Pass-transistor very large scale integration

A CMOS circuit formed in a semiconductor substrate having improved immunity to total ionizing dose radiation, improved immunity to radiation induced latch up, and improved immunity to a single event upset. The architecture of the present invention can be utilized with the n-well, p-well, or dual-well processes. For example, a preferred embodiment of the present invention is described relative to a p-well process wherein the p-well is formed in an n-type substrate. A network of NMOS transistors is formed in the p-well, and a network of PMOS transistors is formed in the n-type substrate. A contact is electrically coupled to the p-well region and is coupled to first means for independently controlling the voltage in the p-well region. Another contact is electrically coupled to the n-type substrate and is coupled to second means for independently controlling the voltage in the n-type substrate. By controlling the p-well voltage, the effective threshold voltages of the n-channel transistors both drawn and parasitic can be dynamically tuned. Likewise, by controlling the n-type substrate, the effective threshold voltages of the p-channel transistors both drawn and parasitic can also be dynamically tuned. Preferably, by optimizing the threshold voltages of the n-channel and p-channel transistors, the total ionizing dose radiation effect will be neutralized and lower supply voltages can be utilized for the circuit which would result in the circuit requiring less power.

Radiation tolerant back biased CMOS VLSI

A Single Event Upset (SEU) resistant latch circuit that uses the Single Event Resistant Topology (SERT) comprises a first circuit module electrically coupled to a second circuit module. In the SERT-1 embodiment, the first circuit module has two output terminals, including four cross-coupled p-channel (PMOS) transistors coupled with two n-channel (NMOS) transistors. The second circuit module has two output terminals, including four cross-coupled p-channel (PMOS) transistors coupled with two n-channel (NMOS) transistors. These four output terminals satisfy a set of state equations that can be used to obtain the SERT-1 State Table. In the SERT-2 embodiment, the first circuit module has two output terminals, including four cross-coupled n-channel (NMOS) transistors coupled with two p-channel (PMOS) transistors. The second circuit module has two output terminals, including four cross-coupled n-channel (NMOS) transistors coupled with two p-channel (PMOS) transistors. These four output terminals satisfy a set of state equations that can be used to obtain the SERT-2 State Table.

Conflict free radiation tolerant storage cell

Growing community of inventors

Albuquerque, NM, United States of America

Gary K Maki