Integrated-circuit die having redundant signal pads and related integrated circuit, system, and method
An integrated-circuit die includes a number of signal paths, and includes a greater number of signal pads that are operable to be coupled to the signal paths. By including more signal pads than signal paths on the die, one can often repair a defect in the connection of a pad to, e.g., a pad of another die, by connecting a signal path to another, i.e., redundant, pad. And such repairing of a pad-connection defect can often increase the yield of the integrated circuits incorporating such a die and/or can extend the lifetime of such an integrated circuit.
1 . An integrated-circuit die, comprising:
a first number of signal paths; and
a second number of signal pads that are operable to be coupled to the signal paths, the second number being greater than the first number.
2 . An integrated circuit, comprising:
a first die, comprising,
a first number of first signal paths, and
a second number of first signal pads that are operable to be coupled to the signal paths, the second number being greater than the first number.
3 . The integrated circuit of claim 2 wherein each of the signal paths is coupled to multiple ones of the signal pads.
4 . The integrated circuit of claim 2 wherein the first die further comprises multiplexing circuitry operable to couple each of the signal paths to a respective one of the signal pads.
5 . The integrated circuit of claim 2 wherein the first die further comprises:
a controller operable to identify as functional signal pads that are able to carry a signal; and
multiplexing circuitry operable to couple each of the signal paths to a respective functional signal pad.
6 . The integrated circuit of claim 2 wherein:
the signal paths comprise electrically conductive paths; and
the signal pads comprise electrically conductive pads.
7 . The integrated circuit of claim 2 wherein:
the signal paths comprise optically conductive paths; and
the signal pads comprise optically conductive pads.
8 . The integrated circuit of claim 2 , further comprising:
a second die comprising,
a third number of second signal paths, and
a fourth number of second signal pads that are operable to be coupled to the second signal paths, each of the second signal pads corresponding to a respective one of the first signal pads, the fourth number being greater than the third number.
9 . The integrated circuit of claim 8 wherein:
the third number equals the first number; and
the fourth number equals the second number.
10 . The integrated circuit of claim 8 wherein each of the second signal paths is coupled to multiple ones of the second signal pads.
11 . The integrated circuit of claim 8 wherein the second die further comprises multiplexing circuitry operable to couple each of the second signal paths to a respective one of the second signal pads.
12 . The integrated circuit of claim 8 wherein:
the first die further comprises,
a first control circuit operable to identify as functional first pads to which a signal can propagate from respective second pads of the second die, and
first multiplexing circuitry coupled to the first control circuit and operable to couple each first signal path to a respective functional first pad; and
the second die further comprises,
a second control circuit coupled to the first control circuit and operable to identify as functional each second pad that corresponds to a respective functional first pad, and
second multiplexing circuitry coupled to the second control circuit and operable to couple each second signal path to a respective functional second pad.
13 . The integrated circuit of claim 8 wherein:
the first die further comprises,
a first control circuit operable to identify as functional first pads to which a signal can propagate from respective second pads of the second die, and
first multiplexing circuitry coupled to the first control circuit and operable to allow unidirectional signal propagation between each first signal path and a respective functional first pad; and
the second die further comprises,
a second control circuit coupled to the first control circuit and operable to identify as functional each second pad that corresponds to a respective functional first pad, and
second multiplexing circuitry coupled to the second control circuit and operable to allow unidirectional signal propagation between each second signal path and a respective functional second pad.
14 . The integrated circuit of claim 8 wherein:
the first die further comprises,
a first control circuit operable to identify as functional first pads to which a signal can propagate from respective second pads of the second die, and
first multiplexing circuitry coupled to the first control circuit and operable to allow bidirectional signal propagation between each first signal path and a respective functional first pad; and
the second die further comprises,
a second control circuit coupled to the first control circuit and operable to identify as functional each second pad that corresponds to a respective functional first pad, and
second multiplexing circuitry coupled to the second control circuit and operable to allow bidirectional signal propagation between each second signal path and a respective functional second pad.
15 . The integrated circuit of claim 8 , further comprising:
a package; and
wherein the first and second dies are disposed within the package.
16 . The integrated circuit of claim 8 wherein the first die is attached to the second die.
17 . An electronic system, comprising:
an integrated circuit, comprising,
a die, comprising,
a first number of signal paths, and
a second number of signal pads that are operable to be coupled to the signal paths, the second number being greater than the first number.
18 . A method, comprising:
determining whether a signal can propagate between a first signal pad on a first integrated-circuit die and a second signal pad on a second integrated-circuit die; and
respectively coupling the first and second signal pads to first and second signal paths that are respectively disposed on the first and second dies if the signal can propagate between the first and second signal pads.
19 . The method of claim 18 wherein determining comprises determining whether the signal can propagate between the first and second signal pads when circuitry on at least one of the first and second integrated-circuit dies is reset.
20 . The method of claim 18 , further comprising respectively isolating the first and second signal pads from the first and second signal paths if a signal cannot propagate between the first and second signal pads.
21 . The method of claim 18 wherein:
determining comprises determining whether the signal can propagate between the first and second signal pads when the signal has a first level and when the signal has a second level; and
coupling comprises respectively coupling the first and second signal pads to the first and second signal paths if the signal can propagate between the first and second signal pads when the signal has the first level and when the signal has the second level.