Patent ID: 6239613
Filing Date: 2001-05-29
Classification: H03K

Abstract:
A programmable logic device comprising:a plurality of first conductors in a first direction;a plurality of second conductors in a second direction;a logic array block;a multiplexer comprising a first input coupled to the logic array block, wherein the multiplexer selectively couples the logic array block to one of the conductors of the plurality of first conductors; anda first tristate device, coupling the logic array block to one of the conductors of the plurality of second conductors, wherein the first tristate device is dynamically controlled by logic in the logic array block, and wherein the first tristate device comprises:a data input;an enable input;a first driver transistor, coupled between a first potential source and an output node;a second driver transistor, coupled between the output node and a second potential source;a first predriver comprising:a first transistor, coupled between the first potential source and a control electrode of the first driver transistor, having a control electrode coupled to an inversion of the enable input;a second transistor, coupled between the control electrode of the first driver transistor and control electrode of the second driver transistor, having a control electrode coupled to the inversion of the enable input; anda third transistor, coupled between the control electrode of the second driver transistor and the second potential source, having a control electrode coupled to the enable input; anda second predriver comprising:a first transistor, coupled between the first potential source and the control electrode of the first driver transistor, having a control electrode coupled to the data input;a second transistor, coupled between the control electrode of the first driver transistor and the control electrode of the second driver transistor, having a control electrode coupled to the enable input; anda third transistor, coupled between the control electrode of the second driver transistor and the second potential source, having a control electrode coupled to the data input.