摘要:
An improved solution for designing a circuit is provided. A set of target paths, each of which has a performance attribute that is targeted for improvement, is obtained from a design for the circuit. An influence for one or more of the nodes in the set of target paths is obtained. One or more of the nodes are selected for improvement using the influence. Subsequently, the performance attribute for each selected node is improved. For example, an implementation of the node can be replaced with an implementation having an improved performance attribute. The relative improvement provided by an alternative implementation versus a relative detriment to another performance attribute can be obtained and used in selecting the node(s) for improvement. In one embodiment, the relative improvement and influence are used to obtain a sensitivity metric for each alternative implementation, which is used in selecting the node(s) for improvement. In this manner, the circuit can be improved in a more effective manner.
摘要:
An improved solution for designing a circuit is provided. A set of target paths, each of which has a performance attribute that is targeted for improvement, is obtained from a design for the circuit. An influence for one or more of the nodes in the set of target paths is obtained. One or more of the nodes are selected for improvement using the influence. Subsequently, the performance attribute for each selected node is improved. For example, an implementation of the node can be replaced with an implementation having an improved performance attribute. The relative improvement provided by an alternative implementation versus a relative detriment to another performance attribute can be obtained and used in selecting the node(s) for improvement. In one embodiment, the relative improvement and influence are used to obtain a sensitivity metric for each alternative implementation, which is used in selecting the node(s) for improvement. In this manner, the circuit can be improved in a more effective manner.
摘要:
A power gated semiconductor integrated circuit comprises: (1) logic circuit to be power gated, said logic circuit having a virtual ground rail; (2) footer device disposed between said virtual ground rail and a ground rail for reducing power consumption of said logic circuit; and (3) virtual rail voltage clamp disposed electrically in parallel with said footer device for limiting the voltage at the virtual ground rail, the virtual rail voltage clamp comprising at least one NFET. A total of Nf NFETs are connected to the virtual ground rail of the integrated circuit for use as both virtual rail voltage clamps and footer devices. A quantity of Nmax-VC NFETs are scanned and perform the function of voltage clamps and the remaining (Nf−Nmax-VC) NFETs perform power gating. Manufacturing variability immunity and tuning of the variability immunity is achieved by adjusting the quantity Nmax-VC based upon testing of the manufactured integrated circuit.
摘要:
A method, system and computer program product for modeling and simulating a powergated hierarchical element of an integrated circuit is disclosed. In modeling a powergated macro, the invention does not model all logic gates or elements as powergated, instead, the invention only models latches as connected to an integrated switch to be powergated. In addition, a fence circuit attached to the powergated macro is modeled as including an extra control signal to force a powergated state of the powergated macro into the fence circuit.
摘要:
A method of checking correctness of scheduling of a circuit where a schedule for the circuit is obtained from a behavioral description. The method comprising extracting loop invariants to determine a sufficient set of acyclic threads when loops are present, performing symbolic simulation to extract the above loop invariants, and proving equivalence of the acyclic threads. Systems, computer systems and computer program products that incorporate the techniques of verification and correctness checking according to the present invention have also been disclosed.
摘要:
A mask reuse methodology process in which the soft logic is implemented with a generic array type cell structure mask and a custom blocking mask. A method is provided comprising printing a set of component cores onto a die at predetermined locations with a reusable mask set; providing a custom blocking mask that includes opaque regions that positionally correspond with the component cores on the die; superimposing the custom blocking mask with a generic array type cell mask to form superimposed masks; and using the superimposed masks to print generic array type cells onto the die with the exception of the predetermined locations where the set of component cores reside.
摘要:
A power gated semiconductor integrated circuit comprises: (1) logic circuit to be power gated, said logic circuit having a virtual ground rail; (2) footer device disposed between said virtual ground rail and a ground rail for reducing power consumption of said logic circuit; and (3) virtual rail voltage clamp disposed electrically in parallel with said footer device for limiting the voltage at the virtual ground rail, the virtual rail voltage clamp comprising at least one NFET. A total of Nf NFETs are connected to the virtual ground rail of the integrated circuit for use as both virtual rail voltage clamps and footer devices. A quantity of Nmax-VC NFETs are scanned and perform the function of voltage clamps and the remaining (Nf-Nmax-VC) NFETs perform power gating. Manufacturing variability immunity and tuning of the variability immunity is achieved by adjusting the quantity Nmax-VC based upon testing of the manufactured integrated circuit.
摘要:
A mask reuse methodology process in which the soft logic is implemented with a generic array type cell structure mask and a custom blocking mask. A method is provided comprising printing a set of component cores onto a die at predetermined locations with a reusable mask set; providing a custom blocking mask that includes opaque regions that positionally correspond with the component cores on the die; superimposing the custom blocking mask with a generic array type cell mask to form superimposed masks; and using the superimposed masks to print generic array type cells onto the die with the exception of the predetermined locations where the set of component cores reside.
摘要:
A power gated semiconductor integrated circuit comprises: (1) logic circuit to be power gated, said logic circuit having a virtual ground rail; (2) footer device disposed between said virtual ground rail and a ground rail for reducing power consumption of said logic circuit; and (3) virtual rail voltage clamp disposed electrically in parallel with said footer device for limiting the voltage at the virtual ground rail, the virtual rail voltage clamp comprising at least one NFET. A total of Nf NFETs are connected to the virtual ground rail of the integrated circuit for use as both virtual rail voltage clamps and footer devices. A quantity of Nmax-VC NFETs are scanned and perform the function of voltage clamps and the remaining (Nf−Nmax-VC) NFETs perform power gating. Manufacturing variability immunity and tuning of the variability immunity is achieved by adjusting the quantity Nmax-VC based upon testing of the manufactured integrated circuit.
摘要:
A mask reuse methodology process in which the soft logic is implemented with a generic array type cell structure mask and a custom blocking mask. A system is provided comprising a mask set having a plurality of reusable masks corresponding to a plurality of hard intellectual property (IP) components; a generic array type cell mask; and a custom blocking mask that includes blocking regions that positionally correspond with a set of IP components printed on a die.