Forum
Forum
Verilog-AMS
Analysis
Modeling
Design
Theory
Welcome, Guest. Please
Login
or
Register.
Please follow the Forum
guidelines
.
Jul 17
th
, 2024, 4:39pm
Home
Help
Search
Login
Register
PM to admin
The Designer's Guide Community Forum
›
Design Languages
›
Verilog-AMS
› Spectre vs Hspice for VerilogA
‹
Previous topic
|
Next topic
›
Pages: 1
Spectre vs Hspice for VerilogA (Read 7836 times)
newic
Senior Member
Offline
Posts: 138
Spectre vs Hspice for VerilogA
May 20
th
, 2011, 6:03pm
I tried out both Spectre & Hspice to simulate a close loop system that written in VerilogA (using cadence ADE). The results are difference. Do you think spectre result is more accurate than hspice result. Why the results have such difference?
Back to top
IP Logged
boe
Community Fellow
Offline
Posts: 615
Re: Spectre vs Hspice for VerilogA
Reply #1 -
May 23
rd
, 2011, 10:11am
Newic,
please be more specific (see also forum guidelines). E.g. how big is the difference, what kind of system did you model, ...
B O E
Back to top
IP Logged
newic
Senior Member
Offline
Posts: 138
Re: Spectre vs Hspice for VerilogA
Reply #2 -
May 23
rd
, 2011, 5:22pm
since it is a close loop system( PI CDR), the difference is actually quite big (hspice default accurate setting).
Tried out several methods on hspice accuracy setting. I only able to get matched results when i set hspice RUNLVL=6 & METHOD=Gear.
There is a mismatch even i set RUNLVL=6 & METHOD=TRAP.
Back to top
IP Logged
Geoffrey_Coram
Senior Fellow
Offline
Posts: 1999
Massachusetts, USA
Re: Spectre vs Hspice for VerilogA
Reply #3 -
May 24
th
, 2011, 6:58am
Some behavioral models simulate poorly because the variables the author chose aren't scaled properly, so the tolerances (appropriate for V's and I's) allow gross inaccuracies in the model variables.
Back to top
If at first you do succeed, STOP, raise your standards, and stop wasting your time.
IP Logged
newic
Senior Member
Offline
Posts: 138
Re: Spectre vs Hspice for VerilogA
Reply #4 -
May 24
th
, 2011, 7:24am
I got to check my ttol setting.
Besides the ttol setting, what else could cause the difference?
Back to top
IP Logged
boe
Community Fellow
Offline
Posts: 615
Re: Spectre vs Hspice for VerilogA
Reply #5 -
May 25
th
, 2011, 2:24am
Newic,
E.g., a simulation of a system that is close to the stability boundary may depend on the solver algorithm used and its implementation.
B O E
Back to top
IP Logged
newic
Senior Member
Offline
Posts: 138
Re: Spectre vs Hspice for VerilogA
Reply #6 -
May 25
th
, 2011, 2:38am
thx for the feedback. There is no stability issue here (a lot of margin).
At least for now, spectre is more accurate for a given ttol.
I think the difference can be reduced if tightening the ttol.
No time to verify this yet.
Back to top
IP Logged
boe
Community Fellow
Offline
Posts: 615
Re: Spectre vs Hspice for VerilogA
Reply #7 -
May 25
th
, 2011, 4:52am
Newic,
A model bug can of course cause this as well.
BTW, plots would be nice...
B O E
Back to top
IP Logged
Pages: 1
‹
Previous topic
|
Next topic
›
Forum Jump »
» 10 most recent Posts
» 10 most recent Topics
Design
- RF Design
- Analog Design
- Mixed-Signal Design
- High-Speed I/O Design
- High-Power Design
- Mixed-Technology Design
Analog Verification
- Analog Functional Verification
- Analog Performance Verification
Measurements
- RF Measurements
- Phase Noise and Jitter Measurements
- Other Measurements
Modeling
- Semiconductor Devices
- Passive Devices
- Behavioral Models
- Transmission Lines and Other Distributed Devices
Design Languages
»» Verilog-AMS
- VHDL-AMS
Simulators
- Circuit Simulators
- RF Simulators
- AMS Simulators
- Timing Simulators
- System Simulators
- Logic Simulators
Other CAD Tools
- Entry Tools
- Physical Verification, Extraction and Analysis
- Unmet Needs in Analog CAD
General
- Tech Talk
- News
- Comments and Suggestions
- Opportunities
« Home
‹ Board
The Designer's Guide Community Forum
» Powered by
YaBB 2.2.2
!
YaBB
© 2000-2008. All Rights Reserved.
Copyright 2002-2024
Designer’s Guide Consulting, Inc.
Designer’s Guide
® is a registered trademark of
Designer’s Guide Consulting, Inc.
All rights reserved.
Send comments or questions to
editor@designers-guide.org
. Consider
submitting
a paper or model.