Capacitance elimination circuit which provides current to a node

Details Capacitance elimination circuit which provides current to a node Capacitance elimination circuit which provides current to a node

1995-12-20

1998-04-07

Callahan, Timothy P.

Miscellaneous active electrical nonlinear devices, circuits, and

Gating

Signal transmission integrity or spurious noise override

327170, 327380, 327391, 326 27, H03K 1716

Patent

active

057368880

ABSTRACT:
A capacitance elimination circuit for eliminating known parasitic capacitance at a node in a circuit. The capacitance elimination circuit is particularly useful at a connection of multiple pass gates in a switch matrix of a programmable logic device (PLD). The capacitance elimination circuit includes a current measuring device including a measuring capacitor having a first end connected to the node having the known capacitance. A second end of the measuring capacitor is connected to a current supply mechanism which provides current to the node to replace current withdrawn by the parasitic capacitance. In one embodiment, the current supply mechanism includes a first current mirror made up of transistors having a first channel type, the first current mirror having one arm coupled to the second end of the measuring capacitor. Another arm of the first current mirror is connected to an arm of a second current mirror made up transistors having a second channel type. Another arm of the second current mirror is then connected to the node to replace current withdrawn by its parasitic capacitance. Current gain provided by the first and second current mirrors is controlled to be substantially equal to current loss due to the parasitic capacitance and the measuring capacitor.

REFERENCES:
patent: 4484147 (1984-11-01), Metz
patent: 5218523 (1993-06-01), Sugishima
patent: 5365118 (1994-11-01), Wilcox

Affiliated with

Also associated with

Rating

Capacitance elimination circuit which provides current to a node does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Capacitance elimination circuit which provides current to a node, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Capacitance elimination circuit which provides current to a node will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-16391