Anyone know if there's an LTspice to PSpice Schematics converter? And vice versa? Ronnie hammond.
It seems it should be relatively easy to do. Both are text format.Jim Thompson - James E.Thompson, CTO mens Analog Innovations, Inc. et Analog/Mixed-Signal ASIC's and Discrete Systems manus Phoenix, Arizona 85048 Skype: Contacts Only Voice:(480)460-2350 Fax: Available upon request Brass Rat E-mail Icon at 1962 AGW proponents are like watermelons. GREEN on the outside, RED on the inside.
Stepping component and model parameters is essential for many SPICE simulations. Some SPICE simulation programs are offering better capabilities than the other. The most convenient and flexible way of stepping SPICE parameters (that I tried) is offered by Micro-Cap from Spectrum Software. Most times you don’t have to change anything in the schematic.
Just check components that you want to step and select the way of stepping. You can also step a lot of different parameters simultaneously.
Unfortunatly, I don’t have access to this software any more. LTSPICE is not offering very convenient and user friendly way to step parameters. However, with LTSPICE you can step more than one parameter simultaneously. This highly influenced my selection of SPICE simulation software, over ORCAD (Cadence) PSPICE. PSPICE was able to step only one parameter at a time. At least I was not able to setup PSPICE to do so. LTSPICE does not offer any user interface enhancements to support stepping of component values and model parameters.
This means that you have to memorize some of this stuff and that’s the reason for this short reference. The first thing that came to my mind as a good example of stepping function in LTSPICE was RLC filter. Files, used in this example are included in. Schematic, used in simulations looks like. Okay, I am at my wit’s end. I’m trying to see the “step values” on the graph, ie., by right clicking the cursor when it shows up as a number. Earlier today, I right clicked the number (after the cursor became a number), and the dialog box popped open and told me which step that was.
So it worked fine and I said “cool”. However, I’m trying to do it again, and it’s not working now!!! I hover over the cursor, it turns into a yellow “1”, and I right click, but then it brings up the context menu for the graph.
Mosfet In Ltspice
I’ve tried everything it seems, but I keep getting the context menu when I right click, and NOT the step value!!! What do I do?????
Download Ltspice Models
Also, “Select steps” from that context menu is greyed out.
Quoting Mike Engelhardt (who develops and maintains LTspice): LTspice understands some hspice syntax. For example, it understands single quotes for parameter substitution as well as '.lib 'file.lib' FAST' syntax. It won't usually be able to understand a '$' symbol as the start of a comment in-line. Usually this is enough to be able to run 3rd party foundry BSIM3 models without modification as long as all dimensions, areas, and perimeters are specified.
LTspice development policy is that went there is a conflict between PSpice and hspice syntax, LTspice will follow PSpice because it a more widely used standard. And also, LTspice does not do the Philips MOS 9 device. As I recall, that model is now open sourced but it is in FORTRAN. Also, I should mention that a general rule is that LTspice does not do the hspice-specific semiconductor enhancements. You can use the 2nd edition of Semiconductor Device Modeling with SPICE by G. Massobrio and P. Antognetti as a good reference for hspice vs PSpice device enhancements.
The PSpice enhancements in that book can be used as an LTspice manual. And then on IBIS, No, IBIS isn't in LTspice. I think IBIS was an Intel invention that allowed them to give behavioral descriptions of their I/O pins without giving out implementation details. Anyway, I think IBIS amounts largely to an IV curve. The DC curve you can put in an IV lookup table. To do the dynamic behavior, you're better off with some kind of transistor level model of the device.
Ltspice Vs Pspice
Attached is an example of using a lookup table in a current source. I don't know if it's otherwise documented anywhere.
Version 4 SHEET 1 880 680 WIRE -32 320 -32 288 WIRE -32 208 -32 176 WIRE -32 176 -160 176 WIRE -160 176 -160 208 WIRE -160 288 -160 320 FLAG -160 320 0 FLAG -32 320 0 SYMBOL current -32 208 R0 SYMATTR InstName I1 SYMATTR Value tbl(-5 -1 -2.5 0 0 1 1 5 2) SYMBOL voltage -160 192 R0 SYMATTR InstName V1 SYMATTR Value 0 TEXT -152 368 Left 0!dc V1 -5 5 1m But from someone else on IBIS and LTspice: I use a free utility from IntuSoft called IBIS2SPICE. It reads in IBIS models (up to version 2.1) and generates an equivalent behavioural spice model. It's originally intended to generate a model compatible with Intusoft's spice, but can be configureed to generate models for other spices based on a template file. There's a templeate file available on the net somewhere to configure it for PSpice models. I can't really vouch for the accuracy of the models it generates, and it's limited to IBIS version 2.1. Generally it would be a great feature to have in LTSpice, but I guess it's not a priority for LT's chip designers, IBIS tends to be used primarily by board designers for board level Signal Integity analysis.
The above comments are from some years ago. Perhaps that will help some.
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