US 8,301,947 B1 · Dynamic scan chain grouping

Abstract

A method and apparatus for dynamic scan chain grouping is disclosed. In one embodiment, an integrated circuit (IC) includes a number of scan partitions. Each scan partition includes a number of scan input ports and a number of corresponding scan output ports. Each scan input port and each scan output port includes a number of scan paths. Additionally, each scan partition includes a number of scan chains. Each scan partition is programmable to couple the scan paths of one of the scan input ports to each of the scan chains. Similarly, the corresponding output port may also be coupled to the scan chains. The scan paths of the remaining scan input ports may be selected to bypass the scan chains of the scan partition, having their respective scan input ports connected directly to their respective scan output ports. Each scan partition may be reconfigurable.

Claims25

Dependent claims

An integrated circuit comprising:

a first scan test partition, wherein the first scan test partition includes:
a first plurality of input ports;
a first selection circuit coupled to each of the first plurality of input ports, wherein the first selection circuit is configured to select one of the first plurality of input ports based on states of a first plurality of selection signals;
a first plurality of scan chains coupled to an output of the first input selection circuit;
a first plurality of bypass circuits each coupled to the first plurality of scan chains and further coupled to corresponding ones of the first plurality of input ports, wherein each of the bypass circuits is configured to couple its corresponding input port to a corresponding one of a first plurality of output ports for which its corresponding input port is not selected by the selection circuit.

2 more elements

A method comprising:

coupling a first one of a plurality of scan input ports of a first partition to one or more scan chains of the first partition;
coupling respective outputs of the one or more scan chains of the first partition to a first one of a plurality of scan output ports of the first partition;
and
coupling remaining ones of the first plurality of scan input ports to a corresponding ones of the plurality of scan output ports of the first partition.

1 more element

A method comprising:

a scan control unit programming a first scan partition to select one of a first plurality of scan ports to be coupled to a first plurality of scan chains;
the scan control unit programming a first scan partition to select remaining ones of the first plurality of scan input ports to bypass the first plurality of scan chains;
the scan control unit programming a second scan partition to select one of a second plurality of scan input ports to be coupled to a second plurality of scan chains, wherein each of the second plurality of scan input ports is coupled to a corresponding one of a first plurality of scan output ports associated with the first scan partition;
and
the scan control unit programming the second scan partition to select remaining ones of the second plurality of scan input ports to bypass the second plurality of scan chains.

2 more elements

An integrated circuit comprising:

a first scan unit having first plurality of scan input ports, a first plurality of scan output ports, and a first plurality of scan chains;
a second scan unit having a second plurality of scan input ports, a second plurality of scan output ports, and a second plurality of scan chains, wherein each of the first plurality of scan output ports is coupled to a corresponding one of the second plurality of scan input ports;
and
a scan control unit configured to:
program the first scan unit to select one of the first plurality of scan input ports and a corresponding one of the first plurality of scan output ports to be coupled to the first plurality of scan chains and select remaining ones of the first plurality of scan input ports to be coupled to corresponding ones of the first plurality of scan output ports such that the first plurality of scan chains are bypassed;
and
program the second scan unit to select one of the second plurality of scan input ports and a corresponding one of the second plurality of scan output ports to be coupled to the second plurality of scan chains and select remaining ones of the second plurality of scan input ports to be coupled to corresponding ones of the second plurality of scan output ports such that the second plurality of scan chains are bypassed.

4 more elements

Dependencies are inferred from the claim text.

Dynamic scan chain grouping

Life of this patent

Dynamic scan chain grouping

Life of this patent

Abstract

Claims25