Method and apparatus for defining an input state vector that achieves low power consumption in digital circuit in an idle state

Apparatus for defining an input state vector for application to circuit inputs of a digital circuit to achieve low power consumption when said digital circuit is in an idle state, said digital circuit comprising one or more circuit elements of respective circuit element types, said apparatus comprising:

• an idle power value source having idle power values stored therein, said idle power values including idle power values for each one of said circuit element types, said idle power values for said one of said circuit element types corresponding to different states of the inputs of a circuit element of said one of said circuit element types;
• and
• an idle power assessor coupled to said idle power value source, said idle power assessor comprising a permutation module configured to identify one or more logically-permissible input connection alterations applicable to said circuit elements of said digital circuit that, when applied to said circuit elements, would reduce said lowest-allowable idle power states of said circuit elements when said digital circuit is in said idle state.

A method for defining an input state vector that achieves low power consumption when applied to circuit inputs of a digital circuit in an idle state, said digital circuit comprising one or more circuit elements of respective circuit element types, said method comprising:

• accessing stored idle power values including idle power values for each one of said circuit element types, said idle power values for said one of said circuit element types corresponding to different digital states of the inputs of a circuit element of said one of said circuit element types;
• and
• for each one of said circuit elements, determining from said stored idle power values digital states of the inputs of said one of said circuit elements that would set said one of said circuit elements to a lowest-allowable idle power state when said digital circuit is in said idle state, said determining accounting for logic constraints of said digital circuit, said states determined for ones of said inputs that constitute said circuit inputs defining said input state vector.

A computer-readable medium having stored thereon computer-readable instructions for causing a computer to perform a method for defining an input state vector for application to circuit inputs of a digital circuit to achieve low idle power consumption when said digital circuit is in an idle state, said digital circuit comprising one or more circuit elements of respective circuit element types, said method comprising:

• accessing stored idle power values, said stored idle power values including idle power values for each one of said circuit element types, said idle power values for said one of said circuit element types corresponding to different digital states of the inputs of a circuit element of said one of said circuit element types;
• and
• for each one of said circuit elements comprising said digital circuit, determining from said stored idle power values, digital states of said inputs of said one of said circuit elements that would set said one of said circuit elements to a lowest-allowable idle power state when said digital circuit is in said idle state, said determining accounting for logic constraints of said digital circuit, said digital states determined for ones of said inputs that constitute said circuit inputs defining said input state vector.