Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Problem with Power nets

Mariammm

Junior Member level 1
Joined
Mar 28, 2021
Messages
16
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
156
Hi ,

I have an inquiry regarding the power nets in power planning step.
when I write get_nets VDD command after derive_pg_connection command, I get this warning message "Warning: No net objects matched 'VDD' (SEL-004)"
So, I can't understand what is the reason for this warning message?!
I attached below a copy of the command execution results.

Thanks in advance

icc_shell> derive_pg_connection -power_net VDD\
-ground_net VSS\
-power_pin VDD\
-ground_pin VSS
Information: connected 18799 power ports and 18799 ground ports
1
icc_shell> get_nets VDD
Warning: No net objects matched 'VDD' (SEL-004)
 

dick_freebird

Advanced Member level 5
Joined
Mar 4, 2008
Messages
7,439
Helped
2,158
Reputation
4,321
Reaction score
2,035
Trophy points
1,393
Location
USA
Activity points
59,556
Are you sure that the power nets should be named
"VDD" and "VSS"? In the tools and PDKs I have used,
"vdd!" and "vss!" (global nets, for inherited connections)
or "vdd", "vss" (for direct-wired schematic design style)
are much more commonly used.

You might inspect one of the logic cells and see
what they think their power pins are called.
 

oratie

Full Member level 6
Joined
Jan 10, 2007
Messages
348
Helped
176
Reputation
350
Reaction score
169
Trophy points
1,323
Activity points
3,694
Try such command "get_nets -all VDD"
 

ThisIsNotSam

Advanced Member level 5
Joined
Apr 6, 2016
Messages
2,175
Helped
382
Reputation
764
Reaction score
396
Trophy points
83
Activity points
11,112
Are you sure that the power nets should be named
"VDD" and "VSS"? In the tools and PDKs I have used,
"vdd!" and "vss!" (global nets, for inherited connections)
or "vdd", "vss" (for direct-wired schematic design style)
are much more commonly used.
VDD and VSS are typical names in digital physical design. vdd!/vss! are more of a custom designer thing.
 

Mariammm

Junior Member level 1
Joined
Mar 28, 2021
Messages
16
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
156
Are you sure that the power nets should be named
"VDD" and "VSS"? In the tools and PDKs I have used,
"vdd!" and "vss!" (global nets, for inherited connections)
or "vdd", "vss" (for direct-wired schematic design style)
are much more commonly used.

You might inspect one of the logic cells and see
what they think their power pins are called.

yes, I inspected them and their power pins are called VDD and VSS.
 

Mariammm

Junior Member level 1
Joined
Mar 28, 2021
Messages
16
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
156
Try such command "get_nets -all VDD"


icc_shell> get_nets -all VDD
{VDD}

This is the result of executing the command. So, does this mean that the Power nets are properly connected?
 

oratie

Full Member level 6
Joined
Jan 10, 2007
Messages
348
Helped
176
Reputation
350
Reaction score
169
Trophy points
1,323
Activity points
3,694
No, it only means, that you have power (or ground) net VDD in the design. Option -all include power/ground nets in get_nets result printing.

Information: connected 18799 power ports and 18799 ground ports - This means, that you have VDD/VSS connected to pins.
 

Mariammm

Junior Member level 1
Joined
Mar 28, 2021
Messages
16
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
156
No, it only means, that you have power (or ground) net VDD in the design. Option -all include power/ground nets in get_nets result printing.

Information: connected 18799 power ports and 18799 ground ports - This means, that you have VDD/VSS connected to pins.


Okay, thank you so much.
 

LaTeX Commands Quick-Menu:

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top