Integrated circuit design method, system and computer program product

1. A method, comprising:

assigning a default voltage value of a voltage domain in an integrated circuit (IC) schematic to a net in the voltage domain, wherein the default voltage value corresponds to a power supply voltage of the voltage domain;

generating a simulation voltage value of the net by performing a circuit simulation on the net using the assigned default voltage value; and

modifying the IC schematic to include a voltage value associated with the net, wherein, in response to a difference between the assigned default voltage value and the simulation voltage value of the net being greater than a predetermined tolerance,

the voltage value associated with the net and included in the modified IC schematic is based on the simulation voltage value of the net.

2. The method of claim 1 , further comprising:

reading the default voltage value from a file.

3. The method of claim 1 , further comprising:

obtaining the default voltage value from a user interface.

4. The method of claim 1 , wherein

the net is one net of a plurality of nets in the voltage domain,

said assigning comprises assigning the default voltage value of the voltage domain to all the plurality of nets in the voltage domain,

said generating comprises generating a simulation voltage value of each of the plurality of nets by performing the circuit simulation on the plurality of nets using the assigned default voltage value, and

said method further comprises causing a user interface to highlight, among the plurality of nets, those nets for each of which the difference between the assigned default voltage value and the simulation voltage value is greater than the predetermined tolerance.

5. The method of claim 1 , further comprising:

in response to the difference between the assigned default voltage value and the simulation voltage value of the net being greater than the predetermined tolerance,

outputting a net identifier of the net, the assigned default voltage value, and the simulation voltage value of the net, and

receiving a user input of the voltage value to be included in the modified IC schematic, based on the outputted assigned default voltage value and the outputted simulation voltage value of the net.

6. The method of claim 1 , wherein

the modifying the IC schematic comprises, in response to the difference between the assigned default voltage value and the simulation voltage value of the net being not greater than the predetermined tolerance,

including the assigned default voltage value as the voltage value associated with the net in the modified IC schematic.

7. The method of claim 1 , wherein

the modifying the IC schematic comprises, in response to the difference between the assigned default voltage value and the simulation voltage value of the net being greater than the predetermined tolerance,

including the simulation voltage value as the voltage value associated with the net in the modified IC schematic.

8. The method of claim 1 , further comprising:

storing the modified IC schematic in a non-transitory, computer readable storage medium.

9. The method of claim 1 , further comprising:

generating a layout diagram corresponding to the modified IC schematic; and

performing a voltage design rule check (VDRC) on the generated layout diagram, the VDRC using the voltage value associated with the net and included in the modified IC schematic.

10. The method of claim 1 , further comprising:

generating a layout diagram corresponding to the modified IC schematic; and

fabricating, based on the generated layout diagram, at least one of:

one or more semiconductor masks, or

at least one component in a layer of a semiconductor IC.

11. A system, comprising:

a user interface; and

a processor configured to

assign a default voltage value of a voltage domain in an integrated circuit (IC) schematic to a net in the voltage domain, wherein the default voltage value corresponds to a power supply voltage of the voltage domain,

generate a simulation voltage value of the net by performing a circuit simulation on the net using the assigned default voltage value, and

in response to a difference between the assigned default voltage value and the simulation voltage value of the net being greater than a predetermined tolerance,

cause the user interface to output a net identifier of the net, the assigned default voltage value, and the simulation voltage value of the net, and

modify the IC schematic to include, in association with the net, a voltage value received via the user interface in response to the outputted assigned default voltage value and the outputted simulation voltage value of the net.

12. The system of claim 11 , wherein

the net is one net of a plurality of nets in the voltage domain, and

the processor is configured to

assign the default voltage value of the voltage domain to all the plurality of nets in the voltage domain,

generate a simulation voltage value of each of the plurality of nets by performing the circuit simulation on the plurality of nets using the assigned default voltage value, and

cause the user interface to highlight, among the plurality of nets, those nets for each of which the difference between the assigned default voltage value and the simulation voltage value is greater than the predetermined tolerance.

13. The system of claim 11 , wherein

the voltage domain is one voltage domain of a plurality of voltage domains in the IC schematic, the plurality of voltage domains having different corresponding default voltage values and corresponding voltage domain identifiers, wherein the different default voltage values correspond to different corresponding power supply voltages of the plurality of voltage domains,

the net is one net of a plurality of nets, each net of the plurality of nets being part of a corresponding voltage domain of the plurality of voltage domains,

the processor is configured to

cause the user interface to output the voltage domain identifiers in association with the corresponding default voltage values,

in response to a user confirmation of the outputted default voltage values, assign the default voltage value of each voltage domain of plurality of voltage domains to the nets in the voltage domain,

perform the circuit simulation on all of the plurality of nets in the IC schematic using the corresponding assigned default voltage values, and

cause the user interface to highlight, among the plurality of nets, those nets for each of which the difference between the assigned default voltage and the simulation voltage value is greater than the predetermined tolerance.

14. The system of claim 11 , wherein

the processor is configured to read the default voltage value from a common power format file.

15. The system of claim 11 , wherein

the processor is configured to obtain the default voltage value input via the user interface.

16. The system of claim 11 , wherein

the processor is configured to store the modified IC schematic in a non-transitory, computer readable storage medium.

17. The system of claim 11 , wherein

the processor is configured to

generate a layout diagram corresponding to the modified IC schematic, and

perform a voltage design rule check (VDRC) on the generated layout diagram, the VDRC using the voltage value associated with the net and included in the modified IC schematic.

18. A computer program product, comprising a non-transitory, computer-readable medium containing instructions therein which, when executed by a processor, cause the processor to

read an integrated circuit (IC) schematic, wherein

the IC schematic comprises a plurality of circuits in a plurality of voltage domains having different corresponding power supply voltages, and

each circuit among the plurality of circuits comprises

power supply nets coupled to power supply terminals of a corresponding voltage domain among the plurality of voltage domains to receive the power supply voltage of the corresponding voltage domain, and

a signal net coupled to another circuit among the plurality of circuits,

assign, to the signal net of each circuit among the plurality of circuits, the power supply voltage of the corresponding voltage domain,

perform a circuit simulation on the IC schematic to obtain a simulation voltage at the signal net of each circuit among the plurality of circuits, and

in response to a difference between the assigned power supply voltage and the simulation voltage at the signal net of a circuit among the plurality of circuits being greater than a predetermined tolerance,

modify the IC schematic to include the simulation voltage in association with the signal net.

19. The computer program product of claim 18 , wherein the instructions, when executed by the processor, further cause the processor to

receive a user input of at least one of

the power supply voltages of the plurality of voltage domains, or

a determination to modify the IC schematic to include the simulation voltage in association with the signal net at which the difference between the assigned power supply voltage and the simulation voltage is greater than the predetermined tolerance.

20. The computer program product of claim 18 , wherein the instructions, when executed by the processor, further cause the processor to

generate a layout diagram corresponding to the modified IC schematic, and

perform a voltage design rule check (VDRC) on the generated layout diagram, the VDRC using the simulation voltage included in the modified IC schematic.