Controlling sequence of simulations in Analog Artist

Hi,
I would like to simulate a transient in order to get a spectre.fc
containing the node voltages that I read in as values for the nodes in
an ac simulation. Problem is that in ADE the ac simulation is executed
before my transient simulation.

I would also like to have a short transient simulation before running
a longer transient simulation. In the first simulation I switch off
all other components in order to find the bias point for my component.
This write the node voltages to spectre.fc which I then use for node
voltages for the second and longer transient simulation with all
external components connected.

I can't find a way to add another transient simulation via ADE.
Directly in a spectre file, I can name them tran1 tran2 tran3 etc. and
the simulations are run sequentially. This way I can also control
which simulation is simulated first.

A pointer to more reading is appreciated.

 

svenn> Hi, I would like to simulate a transient in order to get a
svenn> spectre.fc containing the node voltages that I read in as
svenn> values for the nodes in an ac simulation. Problem is that in
svenn> ADE the ac simulation is executed before my transient
svenn> simulation.

svenn> I would also like to have a short transient simulation before
svenn> running a longer transient simulation. In the first
svenn> simulation I switch off all other components in order to find
svenn> the bias point for my component. This write the node
svenn> voltages to spectre.fc which I then use for node voltages for
svenn> the second and longer transient simulation with all external
svenn> components connected.

svenn> I can't find a way to add another transient simulation via
svenn> ADE. Directly in a spectre file, I can name them tran1 tran2
svenn> tran3 etc. and the simulations are run sequentially. This way
svenn> I can also control which simulation is simulated first.

svenn> A pointer to more reading is appreciated.

svenn> -- Svenn
Hi Svenn

You hit on one of my biggest complaints about ADE -- you can't have more
than one sim of a type. I haven't looked into it closely but there is a
spectre simulator interface that is integrated into the Schematic
Composer...
(deInstallApp (hiGetCurrentWindow) "Spectre-Schematic")
or select Tools->Simulation->Spectre. It does allow you to specify your
own set of simulations.

As far as simulation order is concerned, there is an option for
simulation order under Setup->Environment for spectre direct simulator.

Hope this helps.

Satya

 

wrote in message

You should hear the sound of my teeth. Andrew, would it help to file a
product change request on sourcelink and make a petition for cadence
users to support this request?

Think I have tried this once or twice. It is ok as long as the vendor
is not sticking a design kit on top of your design flow. I view design
kits as those handy first-aid kits you have in a car: They are always
withing reach, but not glued to your dashboard. (another session of
teeth grinding)

Another teeth grinding experience: I use a kit for SpectreS and I
couldn't find that option.

Thanks a lot. I have had my weeks rant over cadence and designkits by
now. Now I can work relaxed for the rest of the week. See you.

 

Hi Svenn,

Just doing a little mild newsgroup reading whilst having a week's vacation...

You're not the only one. Please do ask for this - I've wanted this for years. In
fact there are quite a _lot_ of people who have asked for this.
In effect you can do it with the new Aptivia tool, but it's still not really doing
it by using the simulator's ability to have named analyses.

Unfortunately it's quite difficult to do given the way that ADE is architected.
I know of one (proprietary) simulator at least which worked around this
in ADE, but I believe they had to do quite a bit of hacking to get
it to work...

Still, if people ask for it, and have good arguments for it (other than just
"I want it because it would be neat"), then it all helps...

Hmm, that's a fairly low-featured integration. Not much more than
a netlister - and you can do the same thing with spectre.

In fact what I tend to do if I want more than one analysis of the same type
is to have an include file (sometimes included as a model file, say), with the
analyses I want it to run. I always used this for complex thing like
paramset sweeps, or multidimensional sweeps. In general it works OK, although
some of the postprocessing can get a little upset if you have more than one
analysis of the same type.

Doing this kind of inclusion of a file containing analyses works best with
the spectre, rather than obsolete spectreS, integration.

Please try to move to spectre as fast as possible? The old spectreS interface
is pretty limited, and not going to improve. That was exactly why the new interface
was implemented (as well as cutting cdsSpice out of the loop, because it
was just an obstacle which got in the way most of the time).

The analysisOrder setting then gives you the ability to control the order of the
analyses, exactly as you want.

Andrew.

 

Andrew> Hi Svenn, Just doing a little mild newsgroup reading whilst
Andrew> having a week's vacation...


Andrew> You're not the only one. Please do ask for this - I've
Andrew> wanted this for years. In fact there are quite a _lot_ of
Andrew> people who have asked for this. In effect you can do it
Andrew> with the new Aptivia tool, but it's still not really doing
Andrew> it by using the simulator's ability to have named analyses.

Andrew> Unfortunately it's quite difficult to do given the way that
Andrew> ADE is architected. I know of one (proprietary) simulator
Andrew> at least which worked around this in ADE, but I believe they
Andrew> had to do quite a bit of hacking to get it to work...

Andrew> Still, if people ask for it, and have good arguments for it
Andrew> (other than just "I want it because it would be neat"), then
Andrew> it all helps...

Andrew> Hmm, that's a fairly low-featured integration. Not much more
Andrew> than a netlister - and you can do the same thing with
Andrew> spectre.

Andrew> In fact what I tend to do if I want more than one analysis
Andrew> of the same type is to have an include file (sometimes
Andrew> included as a model file, say), with the analyses I want it
Andrew> to run. I always used this for complex thing like paramset
Andrew> sweeps, or multidimensional sweeps. In general it works OK,
Andrew> although some of the postprocessing can get a little upset
Andrew> if you have more than one analysis of the same type.

Andrew> Doing this kind of inclusion of a file containing analyses
Andrew> works best with the spectre, rather than obsolete spectreS,
Andrew> integration.
Andrew> Please try to move to spectre as fast as possible? The old
Andrew> spectreS interface is pretty limited, and not going to
Andrew> improve. That was exactly why the new interface was
Andrew> implemented (as well as cutting cdsSpice out of the loop,
Andrew> because it was just an obstacle which got in the way most of
Andrew> the time).

Andrew> The analysisOrder setting then gives you the ability to
Andrew> control the order of the analyses, exactly as you want.

Andrew> Andrew.

Andrew> -- Andrew Beckett Senior Technical Leader Custom IC
Andrew> Solutions Cadence Design Systems Ltd

Hi Andrew

As usual you have been more than helpful. However, some of us are stuck
with spectreS because corporate CAD groups are slow to respond to
designer needs.

There is one "feature" of spectreS that is quite neat -- it releases the
license as soon as the simulation is over. spectre on the other hand
ties it up until you quit the Affirma session. While this makes spectre
respond faster, it is also quite expensive when you have all designers
sitting with a few spectre licenses each which they are using for about
20% time. Anyway to set a time-out on spectre license checkout?

Regards
Satya

 

On 30 Oct 2003 15:07:56 -0700, wrote:

Satya,

envSetVal("spectre.envOpts" "controlMode" 'string "batch")

before starting ADE will do what you want. This way each spectre simulation
starts a new spectre, and so the licenses are freed as it exits which the simulation
ends. You pay a little in speed (most noticeable with parametric simulations), but
it saves the license being held up.

We don't support timeout on licenses in general.

Regards,

Andrew.

 

Andrew> On 30 Oct 2003 15:07:56 -0700,
Andrew> wrote: Satya,

Andrew> envSetVal("spectre.envOpts" "controlMode" 'string "batch")

Andrew> before starting ADE will do what you want. This way each
Andrew> spectre simulation starts a new spectre, and so the licenses
Andrew> are freed as it exits which the simulation ends. You pay a
Andrew> little in speed (most noticeable with parametric
Andrew> simulations), but it saves the license being held up.

Andrew> We don't support timeout on licenses in general.

Andrew> Regards,

Andrew> Andrew.

Andrew

Thanks for the tip.

Satya