Passgate structures for use in low-voltage applications
AssigneeAltera Corporation
InventorsAndy L. Lee, Wanli Chang, Cameron McClintock, John E. Turner, Brian D. Johnson, Chiao Kai Hwang, Richard Yen-Hsiang Chang, Richard G. Cliff
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Abstract
Enhanced passgate structures for use in low-voltage systems are presented in which the influence of Vt on the range of signals passed by single-transistor passgates is reduced. In one arrangement, the VGATE−Vt limit for signals propagated through NMOS passgates is raised by applying a higher VGATE; in another arrangement, the Vt is lowered. The use of CMOS passgates in applications where single-transistor passgates have traditionally been used is also presented.
Claims20
A programmable logic device, comprising:
- an array of logic blocks;
- a plurality of interconnect lines;
- and
- a plurality of switches for programmably routing logic signals between the logic blocks over the interconnect lines, wherein each switch includes a passgate transistor, wherein the programmable logic device has low system voltages that are comparable to the threshold voltage of the passgate transistor, and wherein the programmable logic device has a passgate-activating voltage that substantially exceeds the low system voltages.
A programmable logic device, comprising:
- an array of logic blocks including logic transistors;
- a plurality of interconnect lines;
- a plurality of switches for programmably routing logic signals between the logic blocks over the interconnect lines, wherein the switches include passgate transistors having threshold voltages that are substantially lower than the threshold voltages of other transistors in the programmable logic device.
Dependencies are inferred from the claim text.