# Sub circuit in Ltspice.

J

#### Jamie

Jan 1, 1970
0
If I create a sub circuit in LTspice, will that circuit's content be
exported with the main file or do I need to include that along with the
file?
I read the help file but it some what does not give me a fuzzy feeling..

Jamie

J

#### Joerg

Jan 1, 1970
0
Jamie said:
If I create a sub circuit in LTspice, will that circuit's content be
exported with the main file or do I need to include that along with the
file?
I read the help file but it some what does not give me a fuzzy feeling..

If you place the whole subcircuit text into your schematic as a SPICE
directive then it is included. That's how I always do it. Typically to
the left or below so clients have a choice of printing it out along with
the schematic or not.

Much better than needing two files or having to load library parts.

J

#### Joerg

Jan 1, 1970
0
Jim said:
What Joerg suggests is the equivalent of .INCLUDE in other Spice's.
Slows down the loading of the input file. .LIB is faster and more
efficient.

What I meant is .SUBCKT in the input file. I've never had any speed
issues, they load in a second or two. What does take forever is sims
with gapped transformers in there, leakage inductance and all that. And
then the office temp start to rise and rise and rise.

I've got an Intel 1.6GHz dual core in there. Rumors have it that the
Intel i7 could be almost twice as fast. Have you heard and confirmations
in that direction?

T

#### TheQuickBrownFox

Jan 1, 1970
0
Since Analog1 (also 2.20GHz AMD Athlon 64, but WinXP Pro) crashed and
burned, I'm pondering what to replace it with. Mark/qrk is the
resident expert on benchmarking. There's so much Intel malarkey out
there, it's difficult to know what would be best for a simulation
machine.

...Jim Thompson

My cheap i3 laptop would sim circles around those, so $400. You could likely get an ATOM that would do it pretty fast too. Can't beat Costco sometimes. But better and cheaper is already out there too. Kinda wished I'd waited. But if you want *the best*, splurge and build your own machine with a new LG2011 socket W79 motherboard, and a superior EVGA vid card. It takes a while to build the box, PS, and get your HDs and Disc drives and fans first. THEN get the MOBO, CPU, and RAM. They get cheaper over time, so you buy those last. A good, hot, cutting edge build starts at around$2k and goes up from
there. A dual Xeon could run $3k each just for the processors. Those build do hold *some* of their value though. My Atom runs circles around my old 486 EISA though, and I thought that was a hot box, and my Atom is a full computer for$300.

T

#### TheQuickBrownFox

Jan 1, 1970
0
My main office machine is a nice Supermicro dual 8-core AMD Magny Cours
with 32G of RAM and a nice RAID5 disc array. I bought it about a year
ago for a bit under $4k. It runs CentOS 6.2 Linux, with kvm/qemu virtual machines for XP/32 and Win7/64. LTspice flies. Cheers Phil Hobbs It isn't "nice" if it doesn't have USB 3. also needs SATA 3, cause RAID 5 on the old interface spec is no gain.$4k??? Supermicro saw you coming. Or the guy you got to build it for
you.

I'd go with an EVGA dual XEOM MOBO and fill it with 6 or 12 way (core
pairs). Put all my money into the CPUs and MOBO. AMD mobos are all
taking a hit these days, mainly because the idiots embraced and bought
ATI.

Supermicro makes dual CPU mobos. Oh boy. They have always been hugely
overpriced and underfunctioned.

EVGA makes MODERN dual CPU motherboards. Supermicro is like Dell. It
is two year old technology the moment you buy it. With this, even more
than 2 years.

And the price difference is small enough that I stopped buying AMD 8
years ago. Intel Mobos and CPUs scream.

J

#### Joerg

Jan 1, 1970
0
Jim said:
Yup. The real test is simulation. Intel runs all over AMD with toy
apps. AMD kills Intel when it comes to Spice.

Not just there. I have a ruggedized laptop (Gammatech Durabook) with an
AMD Turion 64 that is at least five years old. In a Cypress training
session where compile runs on PSoC code had to be done a lot it blew the
socks off the other guys with their fancy and newer biz laptops. It
always finished first, way earlier.

The Atom on my netbook is different. That is boviously taylored towards
fuel economy and SPICE sims take much longer.

G

#### Gerhard Hoffmann

Jan 1, 1970
0
Am 07.10.2012 21:06, schrieb TheQuickBrownFox:
EVGA makes MODERN dual CPU motherboards. Supermicro is like Dell. It
is two year old technology the moment you buy it. With this, even more
than 2 years.

I'm writing this in a hotel room in Delphi, Greece, on a 17 month old
Dell Precision M6600 17" laptop. Nobody else had 6 GBit/s SATA, USB-3,
16 or 32 GB RAM, Core I7 vpro and such a display at that time.
I have replaced the iron disk first with a OCZ Vortex3 SSD and now both
drives are 512 GB Samsung 830 SSDs. Plugged them in and they worked.
Both the OCZ and the Samsungs give about 500 MBytes/s transfer rate
in the laptop, about the same as a customer's CAD server monster RAID.
LT spice performance is somewhat better than twice that of the server.

I have not yet tried the two SSDs as a RAID-0.
Plus, I'll be able to run CUDA code on the graphics card for

So, please don't tell us that Dell is >2 years back.

regards, Gerhard

T

#### TheQuickBrownFox

Jan 1, 1970
0
How much heavy duty floating point do you do in a day? Have you done
any actual benchmarks for floating point performance between Intel and
AMD?

Cheers

Phil Hobbs

My video card does better performance than either.

As CPUs go, the winner in that race would be, even after being four
years old, the Cell CPU.

I am sorry, but a 20 ms spice sim calculation and a 17 ms calc of the
same sim is not enough to make me decide for the latter.

I have a feeling that modern Intel CPUs beat AMD.

THEN there is the chipset, and supporting Hdw thing too.

T

#### TheQuickBrownFox

Jan 1, 1970
0
Yup. The real test is simulation. Intel runs all over AMD with toy
apps. AMD kills Intel when it comes to Spice.

...Jim Thompson
Total horseshit.

You have been eating moldy Rye bread.

T

#### TheQuickBrownFox

Jan 1, 1970
0
Your video card can't address 32 GB of memory. What's its maximum
sustained bandwidth to main memory? FDTD cycles through all of memory
twice per time step.

Cheers

Phil Hobbs

I'm sorry, but you do not now, nor will you ever have in the future, a
sim circuit where the array requires a 32 GB RAM space to be ran in.

What a ridiculous claim.

T

#### TheQuickBrownFox

Jan 1, 1970
0
I'm sorry, but you do not now, nor will you ever have in the future, a
sim circuit where the array requires a 32 GB RAM space to be ran in.

What a ridiculous claim.

And as far as bandwidth goes, the PCIe bus makes for fast, HUGE data
transfers between video and main RAM as fast as it gets.

They use video cards cores for protein modeling, and seti comm data
parsing. I think they can handle a petty OR a complex circuit sim.

G

#### Gerhard Hoffmann

Jan 1, 1970
0
Am 08.10.2012 00:40, schrieb Jim Thompson:
On Mon, 08 Oct 2012 00:18:50 +0200, Gerhard Hoffmann <[email protected]>

What operating system, Win7 ?

How do you like it? I fear biting that bullet :-(

It came with Win7, I now run Win7 / xubuntu 12.04 dual boot.
Win7 is mostly ignored.

Xilinx/Sigasi FPGA stuff runs natively under Linux, most other
CAD runs in the same XP virtual box that I use at home on
the workstation. Just 'import' a 50 Gig file to the

The C: partition contains ONLY installed programs; D: of the XP
can be seen as D: on win7 and as /d on Linux.

The machine has a drawback: it is quite heavy and can generate
some heat if one asks for it.

regards, Gerhard

M

#### MrTallyman

Jan 1, 1970
0
Am 08.10.2012 00:40, schrieb Jim Thompson:

It came with Win7, I now run Win7 / xubuntu 12.04 dual boot.
Win7 is mostly ignored.

Yeah, as shitty as the last two Ubuntu releases have been, I am sure you
are spending most of your time learning their 'new' 100% pathetic,
"Unity" 'desktop'.

Biggest mistake they ever made. Good luck with that.

XUBUNTU is far better.
Xilinx/Sigasi FPGA stuff runs natively under Linux,

Big whoop. Under Linux the 'stuff' runs at whatever run time it takes
to get it done.

Under Windows 7, non-natively, it takes a whole 5 ms longer.
Big deal.
most other
CAD runs in the same XP virtual box that I use at home on
the workstation. Just 'import' a 50 Gig file to the

I laugh at some of the running around you dorks who "hate Windows" go
out of your way to do. Absolutely pathetic.
The C: partition contains ONLY installed programs; D: of the XP
can be seen as D: on win7 and as /d on Linux.

My machine has about 4TB of HD space, under about 15 partitions.
The machine has a drawback: it is quite heavy and can generate
some heat if one asks for it.

Sounds like a pre-multi-core POS.

J

#### JW

Jan 1, 1970
0
Works well for me, except that I have a few DOS programs that I still
use, which it won't run. (Freelance 4.0 is the biggest problem.) I
have an XP virtual machine on my Supermicro box to handle that sort of
stuff.

Win7 also has an 'XP mode' feature, but it won't run on my standard
laptops.

Somebody mentioned this a while back, but in case anybody missed it.
http://classicshell.sourceforge.net/index.html

It gives Windows 7 (or 8) a more XP like feel.

J

#### josephkk

Jan 1, 1970
0
What I meant is .SUBCKT in the input file. I've never had any speed
issues, they load in a second or two. What does take forever is sims
with gapped transformers in there, leakage inductance and all that. And
then the office temp start to rise and rise and rise.

I've got an Intel 1.6GHz dual core in there. Rumors have it that the
Intel i7 could be almost twice as fast. Have you heard and confirmations
in that direction?

Tell you what, let me get my racehorse running (3.6 GHz hex core, 16 GiB
RAM, SSD) and we can do some timing tests. Not nearly as powerful as
P.Hobbs fast box but should be plenty ok.

?-)

J

#### josephkk

Jan 1, 1970
0
How much heavy duty floating point do you do in a day? Have you done
any actual benchmarks for floating point performance between Intel and
AMD?

Cheers

Phil Hobbs

For pretty much anyone here, that reduces to how much SPICE simulationsdo
you run. If it is a lot, AMD based machines may still have an advantage.
Otherwise not much difference, most anything since a 1.4 GHz P4 is
overkill unless wasted away by the OS and Desktop.

?-)

J

#### josephkk

Jan 1, 1970
0
"As fast as it gets" isn't a number.

The bottleneck in FDTD is main memory bandwidth, because you're cycling
through all allocated memory many many times, so you get a lot of cache
misses. Good caching will help with the main memory latency, because
most accesses are to contiguous memory if you've coded it right.

Did you look up FDTD? What do you think about it?

Cheers

Phil Hobbs

I presume you are aware you are talking to AlwaysWrong.

?-)

J

#### josephkk

Jan 1, 1970
0
Works well for me, except that I have a few DOS programs that I still
use, which it won't run. (Freelance 4.0 is the biggest problem.) I
have an XP virtual machine on my Supermicro box to handle that sort of
stuff.

Win7 also has an 'XP mode' feature, but it won't run on my standard
laptops.

I am presuming you installed the VM subsystem as required.
Cheers

Phil Hobbs

It is starting to sound like it is time for VirtualBox w/ qemu or whatever
else is needed.

G

#### Gerhard Hoffmann

Jan 1, 1970
0
Am 08.10.2012 14:29, schrieb MrTallyman:
On Mon, 08 Oct 2012 08:46:14 +0200, Gerhard Hoffmann <[email protected]>

Yeah, as shitty as the last two Ubuntu releases have been, I am sure you
are spending most of your time learning their 'new' 100% pathetic,
"Unity" 'desktop'.

Biggest mistake they ever made. Good luck with that.

XUBUNTU is far better.
-----------------------

My machine has about 4TB of HD space, under about 15 partitions.

So what. My laptop has 1 TB of SSD. I win.

And as much USB3-attached storage as I might want.
And 2 external sata-3 ports.
Sounds like a pre-multi-core POS.

4 * 2 cores.

M

#### MrTallyman

Jan 1, 1970
0
I presume

You sure do, you retarded little Zimmerman complex ridden bitch.

snipped totally retarded Joe_Seph_KKK stupidity.

You need to grow up, Joe_Seph_KKK. Your Nazi Stupidity is showing,
again.

The video card GPU engine would perform this task as well or better.

As for the PC, I use ECC RAM. It is an old machine.

Modern machines use DDR3 Quad arrays. Probably don't even need ECC.
Certainly don't seem to have the time for it.

Video cards have higher on-board memory bandwidth even than the slot
they are plugged into, much less the PC RAM on the other side of that.

Way faster. He mentioned bottlenecks. Put that in your brain domain,

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