Placement of input-output design objects into a programmable gate array supporting multiple voltage standards

An apparatus for placement of input, output, and bidirectional design objects into IOBs of a programmable gate array, the IOBs of the programmable gate array being located in a plurality of banks programmable to send and receive signals at a plurality of input and output voltage standards, each bank including selected ones of the IOBs, wherein the design objects specify at least one input voltage standard or at least one output voltage standard, comprising:

• means for selecting input voltaae standards for respective ones of the banks;
• means for selecting output voltage standards for respective ones of the banks;
• means for placing input design objects into respective IOBs of the banks to minimize penalty cost of the placement, wherein the input voltage standard of the input design object is compatible with the input voltage standard of the bank in which the respective IOB is located;
• and
• means for placing output design objects into respective IOBs of banks to minimize penalty cost of the placement, wherein the output voltage standard of the output design object is compatible with the output voltage standard of the bank in which the respective IOB is located.

A method for placement of input, output, and bidirectional design objects into IOBs of a programmable gate array, the IOBs of the programmable gate array arranged in a plurality of banks programmable to send and receive signals at a plurality of input and output voltage standards and wherein the design objects specify at least one input voltage standard or at least one output voltage standard, comprising:

• selecting input voltage standards for respective ones of the banks in a way that optimizes placement of a design into the programmable gate array;
• selecting output voltage standards for respective ones of the banks in a way that optimizes placement of a design into the programmable gate array;
• placing input design objects into respective IOBs of banks, wherein the input voltage standard of the input design object is compatible with the input voltage standard of the bank in which the respective IOB is located;
• and
• placing output design objects into respective IOBs of banks, wherein the output voltage standard of the output design object is compatible with the output voltage standard of the bank in which the respective IOB is located.

A method for placement of input, output, and bidirectional design objects into IOBs of a programmable gate array, the IOBs of the programmable gate array arranged in a plurality of banks programmable to send and receive signals at a plurality of input and output voltage standards and wherein the design objects specify at least one input voltage standard or at least one output voltage standard, comprising:

• generating an intermediate placement of the input and output design objects on the IOBs that permits mixing of input voltage standard within a bank and mixing of output voltage standards within a bank;
• assigning input voltage standards and output voltage standards to the banks as a function of the intermediate placement;
• and
• generating a final placement of the input design objects and output design objects while minimizing cost of a final placement, wherein the input voltage standard of each input design object is compatible with the input voltage standard of the bank of IOBs in which input design object is placed, and the output voltage standard of each output design object is compatible with the output voltage standard of the bank of IOBs in which output design object is placed.