System and method for scan chain re-ordering

摘要

A system for re-ordering a scan chain of an electronic circuit design using an electronic design automation (EDA) tool includes a processor and a memory in communication with the processor. The scan chain includes a plurality of scan cells. All connections of the scan chain are disconnected. An output port of a first scan cell is connected to input ports of other scan cells to form a first set of scan cell combinations. A first scan cell combination is selected from the first set of scan cell combinations based on weighted averages of ordering parameters of each of the first set of scan cell combinations. The process is repeated to re-order the scan chain.

主权项

1. An electronic design automation (EDA) tool for selecting a first scan cell combination from a plurality of scan cells in a scan chain of an electronic circuit design for re-ordering the scan chain, the EDA tool comprising:
a timing placement tool that provides a plurality of ordering parameters corresponding to each combination of two scan cells of the plurality of scan cells; a memory that stores the electronic circuit design; and a processor in communication with the memory, wherein the processor is configured for:
disconnecting a first plurality of connections between the plurality of scan cells;identifying a first scan cell from the plurality of scan cells, wherein the first scan cell is at least one of a scan cell that receives a test input signal from an external test apparatus and a scan cell that provides an output signal to the external test apparatus;connecting the first scan cell with each of the plurality of scan cells to form a first plurality of scan cell combinations;determining a plurality of ordering parameters corresponding to each of the first plurality of scan cell combinations using the timing placement tool;determining at least one weighted average of the plurality of ordering parameters corresponding to each of the first plurality of scan cell combinations;arranging the first plurality of scan cell combinations based on the at least one weighted average; andselecting the first scan cell combination based on a predetermined priority of the plurality of ordering parameters.