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Electronics Forum / CAD / March 2005SuperSpice and new component
I need to analyse VERY simple circuit with SuperSpice (or should I use some other program?). Schematics has some resistors and 'special type' of (coax)amplifiers. All that I know about those amplifiers is that their U*I=22,5Watt, but that should be all that I need. It is connected to power supply =63V DC. I want to know the (DC)current that those amplifiers are using and their voltage. How do I add that type of amplifiers to SuperSpice component database? I do not need any complex analysis, just DC voltages and currents. I have used Derive for (numerical) solving system of nonlinear equations, but SuperSpice should be easier for modifying schematics..etc? > I need to analyse VERY simple circuit with SuperSpice You can always email me direct. Support is all free. (or should I use > some other program?). No:-) > Schematics has some resistors and 'special type' > of (coax)amplifiers. All that I know about those amplifiers is that > their U*I=22,5Watt, but that should be all that I need. This don't seem to mean much. Amps have all sorts of specs, like gain, bandwidth, noise, slew rate etc. >It is > connected to power supply =63V DC. > I want to know the (DC)current that those amplifiers are using and > their voltage. > > How do I add that type of amplifiers to SuperSpice component database? I presume you mean the specific amp model which is a ".subckt". ".subckt" models are placed in library text files, usually with the extension .lib. You need to find out what the amp model is. Adding a file with models is just a matter of drag-dropping the file from windows explorer to the SS main window. You aslo ope existing files and past in the model text When you try and place the ".subckt" it will want to be attached to a symbol. The GUI will guide you through selecting an existing symbol, or you can create a block symbol automatically, or draw one from scratch using the symbol editor. > I do not need any complex analysis, just DC voltages and currents. I > have used Derive for (numerical) solving system of nonlinear > equations, but SuperSpice should be easier for modifying > schematics..etc? Yes it is. However, I need more specific info though to sort out your problem. Your amp spec is pretty much meaningless. Kevin Aylward salesEXTRACT@anasoft.co.uk http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. >> Schematics has some resistors and 'special type' >> of (coax)amplifiers. All that I know about those amplifiers is that >> their U*I=22,5Watt, but that should be all that I need. > > This don't seem to mean much. Amps have all sorts of specs, like gain, > bandwidth, noise, slew rate etc. but I really don't need all that. When I try to solve it manually, I write down Kirchhoffs rules and equations for componenets, use math program for numerical solving of system and thats ALL. I just want program to make it easier for me when for eg. removing one resistor. To me, (coax) amplifier is a 'strange' resistor with U=22/I. Its a 'black box' with two wires and I don't wanna know more about it. My problem is calculating ONLY power supply of amps, so it should be really simple to solve it. >>It is >> connected to power supply =63V DC. [quoted text clipped - 6 lines] > ".subckt" models are placed in library text files, usually with the > extension .lib. You need to find out what the amp model is. yes, (but its not really an 'amp' to me, at least not now) >>> Schematics has some resistors and 'special type' >>> of (coax)amplifiers. All that I know about those amplifiers is that [quoted text clipped - 9 lines] > resistor. > To me, (coax) amplifier is a 'strange' resistor with U=22/I. An amplifier is not a resister. The problem here, is that you are essentially, talking gibberish. "U" means nothing, other then as a referance desigater. >Its a > 'black box' with two wires and I don't wanna know more about it. But *we* need to know what your talking about to help you. You are using notation that means, essentially, nothing in electronics. > problem is > calculating ONLY power supply of amps, so it should be really simple > to solve it. Probably is, if you can tell us what you are actualy trying to do. Do you mean somting to do with V=IR or V=P/I Until you formulate you problem correctly, or explain in more detail what you are trying to do so we can formulate it for you, no one can help you. Kevin Aylward informationEXTRACT@anasoft.co.uk http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. Oi, I happened to be in my registry today. I had a look at your software once and then uninstalled it. What's that anasoft/superspice crap doing in my registry? DNA > Oi, I happened to be in my registry today. I had a look at your > software once and then uninstalled it. What's that anasoft/superspice > crap doing in my registry? Well, it just stays there. It don't do anything. Its completely passive. You can just delete the whole lot if you want. I did have a go once at improving the delete on uninstall, but it got to be a bit of pain with the install/uninstall program I use. Kevin Aylward informationEXTRACT@anasoft.co.uk http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. you once said: 'To construct a non-linear resistor, one can set up a voltage dependent current source as a non-linear function of its own terminal voltage. I've never tried it, but believe a behavioral source's describing function can include frequency. But even if you could, why would you wish to model a non realizable component?' What I need is to 'construct' a nonlinear resistor that has: I=P/U (P=const.=22.5Watt) how do I do it? > you once said: > [quoted text clipped - 8 lines] > > how do I do it? Until you tell us what "U" is, we don't know. Do you want to confirm it might be "V", for voltage? Kevin Aylward informationEXTRACT@anasoft.co.uk http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. of course it means the same as V.. I've been using symbol U as voltage for years in school.. so I thought everyone else used it too, my mistake., sorry The 'amplifier' has constant power: V*I=22.5Watt, that is it, nothing more.. I have been trying to use your users guide and part that describes: 3.2.3. Non-linear Dependent Sources but as you can see I'm a total newbie and need help badly.. >of course it means the same as V.. I've been using symbol U as voltage >for years in school.. so I thought everyone else used it too, my [quoted text clipped - 6 lines] > 3.2.3. Non-linear Dependent Sources >but as you can see I'm a total newbie and need help badly.. Just use a G source (behavioral), where G = W/V (W=22.5) I don't know SuperSpice, but that expression _might_ cause convergence issues. If so try: G = W/(abs(V)+0.001) to avoid a divide by zero. ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. > of course it means the same as V.. I've been using symbol U as voltage > for years in school.. so I thought everyone else used it too, my [quoted text clipped - 6 lines] > 3.2.3. Non-linear Dependent Sources > but as you can see I'm a total newbie and need help badly.. Hello orange, this is an example how you would write it in a netlist. B1 is a behaviorial current source. The current is I = const/actual_voltage . B1 a 0 I=22.5/V(a) What you see above is SPICE instruction line. It can be also the result of a schematic containing a B-source. I have attached a schematic file from another SPICE program. It's LTspice. This example sweeps the voltage from 20V to 60V. You can download LTspice with this link. http://ltspice.linear.com/software/swcadiii.exe There are many other SPICE programs around, but not all have behavioral sources. Best Regards, Helmut This is the schematic file "test.asc". Version 4 SHEET 1 880 680 WIRE 32 208 32 160 WIRE 32 336 32 288 WIRE 32 368 32 336 WIRE 208 160 32 160 WIRE 208 208 208 160 WIRE 208 336 32 336 WIRE 208 336 208 288 FLAG 32 368 0 FLAG 208 160 a SYMBOL voltage 32 192 R0 SYMATTR InstName V1 SYMATTR Value 63 SYMBOL bi 208 208 R0 SYMATTR InstName B1 SYMATTR Value I=22.5/V(a) TEXT 32 80 Left 0 !.dc V1 20 100 1 TEXT 40 24 Left 0 ;I = P / V you said: >Hello orange, >this is an example how you would write it in a netlist. >B1 is a behaviorial current source. The current is >I = const/actual_voltage . >B1 a 0 I=22.5/V(a) >What you see above is SPICE instruction line. yes, that is what i need, but how to do it in super spice? I have tried modifying 'functional' component named COS_XN like this: .SUBCKT COS_XN _ssi_pin0 1 * _SS_Symbol [C:\Program Files\AnaSoft\SuperSpice\system\SchematicBlocks.ssm] [2PinBlock] B1 _ssi_pin0 1 I=22/(V(_ssi_pin0,1)) .ENDS but it doesn't work. Please tell me how to make it work. BTW, does ltspice have nice and greatlooking GUI like superspice? Can I easily draw schematics in it? I don't wanna type in node numbers and elements like in old spice, ever. it works!! :)) where do I set how many digits of precision is needed? > it works!! :)) > where do I set how many digits of precision is needed? Not sure what you mean by this. The calculation itself always uses the full range that the compiler supports, which is something like 12 digits of accuracy. This never need setting. You can change the number of digits displayed by clicking on the graph and going to the Options/misc tab. The default is usually quite adequate. Kevin Aylward informationEXTRACT@anasoft.co.uk http://www.anasoft.co.uk SuperSpice, a very affordable Mixed-Mode Windows Simulator with Schematic Capture, Waveform Display, FFT's and Filter Design. >> it works!! :)) >> where do I set how many digits of precision is needed? [quoted text clipped - 4 lines] >digits displayed by clicking on the graph and going to the Options/misc >tab. The default is usually quite adequate. I see, ok but i have another problem now: convergence :(( I have found in manual that you could set initial guess for some voltages and currents that helps iteration process. >.NODESET: Specify Initial Node Voltage Guesses > 4.2.1. .NODESET: Specify Initial Node Voltage Guesses > General form: > .NODESET V(NODNUM)=VAL V(NODNUM)=VAL ... where do I enter this in superspice? (I'm hoping that guessing will help iteration) I've got 19 of those nonlinear components we talked about (I=const/V). With smaller circuits (12 of them), everything is ok All I need is operating point analysis and for relativelty large voltages (~30V) and currents (~1A) I made a mistake, there are 29 of them. When I remove just 3, it works. Maybe that means its not possible in reality to supply all of them? I need one more thing (less important): is it possible somehow to set values of all resistors to =const*R ? (I have to calculate resistors, for eg. R1=150m *0.00528 Ohm/m it would be a lot easier to simply enter meters and let your program calculate resistance) -- Qmnon fgr ebg-binyv orangeKDS, > BTW, does ltspice [...]Can I easily draw schematics in > it? I don't wanna type in node numbers and elements > like in old spice, ever. LTspice had integrated schematic capture. It also lets you add SPICE directives on the schematic and has dialog boxes that let you mix and match editing the SPICE syntax in text or checking boxes on a dialog box. You might want to check it out. More full licenses of LTspice are distribed per day than, say, PSpice/Schematic/ Orcad does in a year. --Mike >orangeKDS, > [quoted text clipped - 11 lines] > >--Mike And Wimpows has even more licenses than LTSpice ;-) ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. Jim, > > More full licenses of LTspice are distributed per day than, > > say, PSpice/Schematic/ Orcad does in a year. > > And Wimpows has even more licenses than LTSpice ;-) Wrong-Horse-Thompson -- stuck in the wrong simulator saddle again! --Mike >Jim, > [quoted text clipped - 7 lines] > >--Mike Could be. However one of my clients tried LTSpice on a *complex* BiCMOS circuit and got spurious results, not matching actual performance like PSpice did. I suspect that your speed-up algorithms, just ducky for SMPS, can skip over important stuff in other types of circuits. ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. Jim, >>>> More full licenses of LTspice are distributed per day than, >>>> say, PSpice/Schematic/ Orcad does in a year. [quoted text clipped - 12 lines] > I suspect that your speed-up algorithms, just ducky for SMPS, > can skip over important stuff in other types of circuits. Nothing that speeds up the SMPS stuff would corrupt the BiCMOS results. The SMPS stuff doesn't impact the SPICE stuff, its a library of ABM, special devices, and HDL's w/ some VerilogA-type extensions. Anyway, people upgrade routinely from PSpice and hspice to LTspice for it's speed, *accuracy*, and convergence specifically in BiCMOS full-chip simulation. LTspice was first a IC simulation tool and second a SMPS tool. BTW, it now has a new data file format called Fast Access that allows you to load waveforms from full chip sims extremely fast, i.e., if you have a 5G file with 2K data traces the load time for a new trace drops from 5min to 1sec with not one bit loss of accuracy. I'd have to see the circuit to tell what happened. Please feel free to send the files I need to duplicate the problem and I can tell you what the problem was. Just to rub it in, last time you sent me a nelist, LTspice gave the correct result and PSpice gave the wrong one because it isn't as accurate at integrating differential equations. The most effective thing for me would be if you first make sure you're using the current version(2.13x) and see if the problem occurs both in the Normal and Alternate solver(Tools=>Control Panel=>SPICE=> Solver) Regards, --Mike >Jim, [snip] >I'd have to see the circuit to tell what happened. >Please feel free to send the files I need to duplicate [quoted text clipped - 13 lines] > >--Mike qrk/Mark, Could you send Mike the circuit? I don't recall now what was involved. ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >More full licenses of >LTspice are distribed per day than, say, PSpice/Schematic/ >Orcad does in a year. And more are deleted :-) Actually, LTspice seems to be getting slightly better, but is a board level simulator. If that's you're purpose, then fine. If you're doing IC's, it will soon disappoint. It still doesn't seem to be able to handle simple hspice models for resistors and capacitors. (specified by w/l). These are simple things, but not needed for board level work. I haven't tried using a multiplier ( m=) for bipolars, but this didn't seem to work when I tried it a while back in a bandgap. A multiplier isn't in the LTspice documentation for bipolars, so it's really not there anyway. Again, if you're not doing a lot of device level work using bipolars, this isn't too much of a problem. There are many things like this you run into when trying to use LTspice for IC's. So LTspice is a board level simulator with nice graphics. There are many undocumented features in LTspice that people have reverse engineered, but a user shouldn't have to do that. I looked at Simetrix recently and they can't do m= (mutipliers) on capacitors, so LTspice has them beat there. They have a native linux version though and that sure is tempting. Both LTspice and Simetrix run well on my AMD 64 box under SuSE9.2. Ltspice really does run well under wine. I was impressed. I didn't do benchmarks, so have no way of knowing at this point how the extra overhead might affect a long simulation. What impressed me most I think was the ease with which this software loaded and ran. As a new linux administrator (used unix for years), I've struggled with getting other software to run. Loading LTspice was a joy in comparison. 64 bits? No problem. I tried recently to get ECS/Synario/Cohesion/Lakers_AMS schematic capture to run under SuSE9.2. It's libraries are dependent on Redhat V3 and gets glibc errors under SuSE. Smartspice won't even let you try their software if you tell them you have anything besides Redhat V3. They don't support anything else. End of story. They're nice about it though :-) Looks like I chose the wrong distro for my linux box. I'm going to have to switch over to Redhat since that's what the engineering software companies seem to have standardized on. From what I understand the different distros use the same libraries, but have arranged them differently? If true it makes one wonder if the word duh means anything to these folks. Then again, why is it some vendors seem to be able to write distro independent software for linux and while others can't? Regards, Larry Larry, > Actually, LTspice seems to be getting slightly better, > but is a board level simulator. If that's you're purpose, [quoted text clipped - 4 lines] > These are simple things, but not needed for board level > work. I have people upgrading from hspice to LTspice to for IC design. For accuracy. --Mike On Sun, 20 Mar 2005 19:07:39 GMT, "Napolean Engelhardt" <nospam@spam.org> wrote: >Larry, > [quoted text clipped - 9 lines] >I have people upgrading from hspice to LTspice to for IC >design. For accuracy. in your dreams. :-) >On Sun, 20 Mar 2005 19:07:39 GMT, "Napolean Engelhardt" ><nospam@spam.org> wrote: [quoted text clipped - 14 lines] > >in your dreams. :-) ldg, You harp about things that you know not about. LTSpice can run ANY netlist... you're just too much the amateur to understand how. If only Mike would make his simulation engine talk to my venerable old MicroSim Schematics he'd likely have a convert. ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. On Sun, 20 Mar 2005 20:23:13 -0700, Jim Dynamite <thegreatone@example.com> wrote: >dg, You harp about things that you know not about. LTSpice can run >ANY netlist... you're just too much the amateur to understand how. Really? :-) Didn't know I was harping. What things are you worried about? Just the parts about devices? I said: o LTspice can't handle resistor and capacitors specified with w/l and models. (It can actually run resistors this way with various error messages, but it's undocumented.) You can use undocumented features if you like. I usually choose not to. I have run circuits in ltspice with resistors to use the graphics, but always have checked the results with other simulators. I like using multiple simulators anyway as a cross check so this isn't unusual. I don't like seeing the error messages LTspice gives with these models. Caps don't seem to work at all specified this way, but aren't supposed to: Syntax: Cnnn n1 n2 <capacitance> [ic=<value>] + [Rser=<value>] [Lser=<value>] [Rpar=<value>] + [Cpar=<value>] [m=<value>] + [RLshunt=<value>] ********** LTSPICE test ********************************************************* .model pp c cox=9e-04 capsw=2.5e-11 del=0.045e-6 + tref=25 tc1=22e-6 tc2=0.0 ********************************************************* V1 1 0 pulse(0 5 5u 1n 1n 1) R1 1 2 1e5 C1 2 0 5p m=1 R3 1 3 1e5 C3 3 0 PP W=33.33U L=33.33U M=5 *c3 3 0 1p m=5 .tran 1u 15u .end ********************************************************* Perhaps you can show me how to run this netlist in LTspice? It will run in smartspice just fine. I guess it literally "runs" in LTspice, but seems to give the wrong answer when the cap is specified by w/l and uses a typical foundry model. A lot of this is preference. I did my own layouts for years and now hire others to do it. I've found it more accurate to design resistors and capacitors myself rather than giving the layout person so much leeway by specifying values. I also use the foundry specified models for these devices during simulation. I'd be interested in how a professional organizes their workflow. How about teaching me a few things? As I recall you use the old Microsim schematic capture for layout and simulate in pspice. Is this the perfect solution (and we should all copy) or do you do this for some other reason? Do you do your own layout? What tools do you use? o No M= on Bipolars? ********** Symbol Names: NPN, PNP, NPN2, PNP2 Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area] + [off] [IC=<Vbe, Vce>] [temp=<T>] ********** I don't see it in the documentation. It may by now be an undocumented feature and I haven't tried this lately. Again, you're free to draw as many parallel devices and work-arounds as you like. I'm trying to avoid this. Thanks for any professional advice :-) Regards, Larry > On Sun, 20 Mar 2005 20:23:13 -0700, Jim Dynamite > <thegreatone@example.com> wrote: [quoted text clipped - 85 lines] > Regards, > Larry Hello Larry, the multiplier for Q is now in the LTspice documentation and it's implemeted. I wonder why it is exactly the same text as you posted. ---- From the manual ------- Q. Bipolar transistor Symbol Names: NPN, PNP, NPN2, PNP2 Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area] + [off] [IC=<Vbe, Vce>] [temp=<T>] ---- End ---- To all here, don't make personal attacks. It doesn't help the technical discussions. Best Regards, Helmut PS: I am not an employee off Linear Technology. Useful links: LTspice/SwitcherCAD: www.linear.com User group: http://groups.yahoo.com/group/LTspice/ I am one of the two moderators of this group. >Hello Larry, >the multiplier for Q is now in the LTspice documentation and it's [quoted text clipped - 9 lines] >Syntax: Qxxx Collector Base Emitter [Substrate Node] model [area] > + [off] [IC=<Vbe, Vce>] [temp=<T>] Thanks Helmut, This is very useful to know. You say it is in the LTspice documentation, but where? I know I'm needing better glasses, but I'm having trouble finding the [M=<M>] in the above text. Is there other documentation posted for this simulator other than the help file? Like I said, LTspice keeps getting better :-) Regards, Larry >>Hello Larry, >>the multiplier for Q is now in the LTspice documentation and it's [quoted text clipped - 21 lines] >Regards, >Larry "[area]" is a number, it IS NOT SPECIFIED as M=, except in non-standard-conforming sh.t-for-brains simulators. If you think HSpice is a good simulator you must be awfully young, or substantially isolated from the real world ;-) ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >"[area]" is a number, it IS NOT SPECIFIED as M=, except in >non-standard-conforming sh.t-for-brains simulators. Really? How interesting. It's not an accepted spice "lexicon"? Since Helmut says this has been implemented in LTspice now, this simulator also is bad? So using a 6 bit dac example again, you wouldn't weight the transistors 1,2,4,8,16,32? Or you would just place 64 transistors? Perhaps you'd write a subcircuit to create the M= function yourself? Or maybe you'd try to make the transistors physically larger so the current densities would match? The dacs I've done seemed to be help greatly by doing these arrays. It also seemed to me that if you want things to match they should be the same, hence the arrays. Using M= greatly simplifies this. Regards, Larry >>"[area]" is a number, it IS NOT SPECIFIED as M=, except in >>non-standard-conforming sh.t-for-brains simulators. > >Really? How interesting. It's not an accepted spice "lexicon"? Nope. Get out a 2G6 or 3F5 manual. >Since Helmut says this has been implemented in LTspice now, this >simulator also is bad? No. Knowing Mikey, I would bet the farm that he's implemented ANY variation of the scheme, to allow netlists from any source. >So using a 6 bit dac example again, you wouldn't weight the >transistors 1,2,4,8,16,32? Or you would just place 64 transistors? I'd just place the number after the ModelName per the standard. No M= called for. >Perhaps you'd write a subcircuit to create the M= function yourself? >Or maybe you'd try to make the transistors physically larger so the [quoted text clipped - 6 lines] >Regards, >Larry ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >I'd just place the number after the ModelName per the standard. No M= >called for. So you have different models for different sized devices? >>I'd just place the number after the ModelName per the standard. No M= >>called for. > >So you have different models for different sized devices? What part of "place the NUMBER after the ModelName per the standard" do you have a problem with? Q1 C B E [SUB} ModelName 5 <<<<---- Do you get it yet ?:-) "Different sized" is a different game than "area". "area" just creates multiple instances (paralleled devices). "Different sized" implies different emitter size, or layout strategy. These have different models, for instance.... .MODEL ab05a npn [snip] .MODEL ab05ai npn [snip] .MODEL ab16ai npn [snip] .MODEL ab1a npn [snip] .MODEL ab1ai npn [snip] .MODEL ab2a npn [snip] .MODEL ab2ai npn [snip] .MODEL ab4ai npn etc.... Keith will probably recognize these names of a MAJOR semiconductor house ;-) ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >>>I'd just place the number after the ModelName per the standard. No M= >>>called for. [quoted text clipped - 7 lines] > >Do you get it yet ?:-) I misread your post. Sorry. I see that you're using <area> as a multiplier. This spice "lexicon" really isn't such a good standard, is it? To me it would be better to have one syntax for a multiplier that can be used across the devices. Hspice and smartspice seem to have settled on m= for this. In fact, multiples are calculated by multiplying area*m with 1 being the default for both. If I could summarize, so far your professional approach seems to be using subcircuits to get around Pspice simulator issues which you justify the need for by pointing out that the original spice didn't have more functionality anyway? Or did I miss something? Many (maybe all?) of these work-arounds simply aren't needed anymore and are things I used for years, then rejected when a simpler approach became available. Some call this progress. Others call it an improper spice lexicon or some such thing. You also seem to take great pride in creating all of these pspice compatible model files from the original foundry files. I prefer not to edit the foundry given model files at all and treat these files as "gold". It also makes it much simpler to incorporate updates. LTspice parses the foundry models files without all the modifications, so it would be preferable to your approach I'd think. Regards, Larry >>>>I'd just place the number after the ModelName per the standard. No M= >>>>called for. [quoted text clipped - 10 lines] >I misread your post. Sorry. I see that you're using <area> as a >multiplier. That is the Spice "Standard" >This spice "lexicon" really isn't such a good standard, is it? To me >it would be better to have one syntax for a multiplier that can be >used across the devices. Hspice and smartspice seem to have settled >on m= for this. In fact, multiples are calculated by multiplying >area*m with 1 being the default for both. To those of us who stopped netlisting by-hand maybe 20 years ago, this is no longer an issue... the symbol TEMPLATE does all the work. >If I could summarize, so far your professional approach seems to be >using subcircuits to get around Pspice simulator issues which you >justify the need for by pointing out that the original spice didn't >have more functionality anyway? Or did I miss something? You've missed a lot. There are a limited number of NATIVE DEVICES is Spice, all else are subcircuits. >Many (maybe all?) of these work-arounds simply aren't needed anymore >and are things I used for years, then rejected when a simpler approach >became available. Some call this progress. Others call it an >improper spice lexicon or some such thing. I call it "head-up-the a.s syndrome". You are really so clueless I might suppose your father is Fred Bloggs ;-) >You also seem to take great pride in creating all of these pspice >compatible model files from the original foundry files. I prefer not >to edit the foundry given model files at all and treat these files as >"gold". It also makes it much simpler to incorporate updates. Excuse me? What makes you think I edit the original foundry files? >LTspice parses the foundry models files without all the modifications, >so it would be preferable to your approach I'd think. > >Regards, >Larry I really am tiring of trying to help what appears to be a student, only to have them turn on me, implying I know nothing. If you're on this side of the pond you are so ignorant you must be a Democrat. Other side of pond, you must be a relative of Bemelman. You're definitely a fookin' amateur ;-) ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >I really am tiring of trying to help what appears to be a student, >only to have them turn on me, implying I know nothing. >You're definitely a fookin' amateur ;-) Of course I didn't ask others recently how to search my hard drive :-) Regards, Larry >Hello Larry, >the multiplier for Q is now in the LTspice documentation and it's [quoted text clipped - 11 lines] > >---- End ---- Hi Helmut, Is [area] the multiplier you were referring to? Sorry if I misunderstood your post. I've gotten used to using m= in Smartspice for all devices. I guess I like the uniformity. Regards, Larry >On Sun, 20 Mar 2005 20:23:13 -0700, Jim Dynamite ><thegreatone@example.com> wrote: [quoted text clipped - 12 lines] >messages, but it's undocumented.) You can use undocumented features >if you like. I usually choose not to. Sure it can. In most Spices, it's done with subcircuits... xR node1 node2 <stray nodes> ModelName Params: L=100u W=2u M=4 >I have run circuits in ltspice with resistors to use the graphics, but >always have checked the results with other simulators. I like using >multiple simulators anyway as a cross check so this isn't unusual. I >don't like seeing the error messages LTspice gives with these models. HSpice and "Smart"Spice tend to run NON-SPICE-STANDARD notation just to be ass-holes and thwart portability. But my particular schematic capture can write out netlists in multiple templates, so I can presently write in PSpice, LVS (for any layout editor) and SmartSpice/HSpice formats. There IS an issue with computational notation, {...} or '...' , but that was solved this weekend (see below). >Caps don't seem to work at all specified this way, but aren't supposed >to: [quoted text clipped - 4 lines] > + [Cpar=<value>] [m=<value>] > + [RLshunt=<value>] Done the same way as R's... xC node1 node2 <stray nodes> ModelName Params: L=100u W=20u (Some nutcases use an M here, I don't, it's confusing... for segmented R's I may adopt "S") >********** > [quoted text clipped - 24 lines] >A lot of this is preference. I did my own layouts for years and now >hire others to do it. Same here. >I've found it more accurate to design resistors >and capacitors myself rather than giving the layout person so much >leeway by specifying values. Likewise. Amazing how fast a digital layout guy can screw-up an Analog layout. > I also use the foundry specified models >for these devices during simulation. (I have models for well over 100 processes/foundries.) I'm a circuit designer, thus I THINK in values, NOT physical dimensions. Layout people like dimensions (naturally :). I can netlist that way (using alternate templates), backing out the dimensions by Algebraic computations {...functions...}, but this doesn't help the layout guy (we like to minimize human intervention :). So, this weekend, my oldest son wrote an executable for me that reads in a netlist, computes all the {...} and fills in numbers for L and W, making for a clean, untouched by human hands, LVS netlist. After refinement, we will put it up for sale on his website. >I'd be interested in how a professional organizes their workflow. How >about teaching me a few things? As I recall you use the old Microsim [quoted text clipped - 3 lines] > >o No M= on Bipolars? Spice STANDARD is A= , but the literal is assumed, not written... Q1 C B E [SUB} ModelName 5 <<--- >********** >Symbol Names: NPN, PNP, NPN2, PNP2 [quoted text clipped - 9 lines] >Again, you're free to draw as many parallel devices and work-arounds >as you like. I'm trying to avoid this. Just showed you how above ;-) >Thanks for any professional advice :-) > >Regards, >Larry ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >Sure it can. In most Spices, it's done with subcircuits... > >xR node1 node2 <stray nodes> ModelName Params: L=100u W=2u M=4 I used to do such things when I used pspice. It causes you to look for ways around its limitations. Unless doing a subcircuit adds accuracy to the simulation, it's difficult for me to understand how doing this is better. Once in a while I use a capacitor symbol, for instance, that calls a subcircuit to add stray to ground. This stray is constantly present in an IC and if you don't account for it, it can cause real problems. It isn't needed all the time, so I just change the pointer to another symbol in another directory and it netlists out normally. <snip> Done the same way as R's... xC node1 node2 <stray nodes> ModelName Params: L=100u W=20u (Some nutcases use an M here, I don't, it's confusing... for segmented R's I may adopt "S") *********** It's less confusing to place the same capacitor over and over again? If you say so. Lets say you were drawing a 6 bit switched capacitor mdac. This means you have to draw 1,2,4,8,16,and 32 cap arrays (in subcircuits perhaps?). Or you could do one of your workarounds and create the m=<M> function yourself I suppose. Then you'd have to figure out how to do an lvs netlist for layout. You also could simply make the caps sequentially larger, but I know you wouldn't do that because of matching issues and the chance of confusing the layout person. In any case, if I have a choice of simply adding m=32 on a cap, I'll do this instead. If the schematic capture supports iterated instances, I've also created these arrays by adding the appropriate instance name on the device. C[0:31] Regards, Larry "nutcase" >>Sure it can. In most Spices, it's done with subcircuits... >> [quoted text clipped - 4 lines] >accuracy to the simulation, it's difficult for me to understand how >doing this is better. A "resistor" is a NATIVE Spice device. If it has more than two terminals, or has parameters, it's a "subcircuit". >Once in a while I use a capacitor symbol, for instance, that calls a >subcircuit to add stray to ground. This stray is constantly present >in an IC and if you don't account for it, it can cause real problems. >It isn't needed all the time, so I just change the pointer to another >symbol in another directory and it netlists out normally. Since I have 100's of clients and 100's of models, I create my own symbol set with Templates appropriate to the process. For instance I don't just place an NMOS device, I place an XFAB-NMOS, so that its strays are properly computed per the process. ><snip> >Done the same way as R's... [quoted text clipped - 6 lines] > >It's less confusing to place the same capacitor over and over again? Sorry, I went back and placed the modifier after the wrong device. I use M= on capacitors all the time. I have so many different types of capacitors (in silicon) that I probably have 20 different symbol types. I just find M= for resistors confusing... parallel?? or serial?? >If you say so. > [quoted text clipped - 3 lines] >m=<M> function yourself I suppose. Then you'd have to figure out how >to do an lvs netlist for layout. Naaaah! You missed the BEAUTY of my schematic capture. The simulation TEMPLATE and the LVS TEMPLATE are different. For instance, MOS devices, in the LVS netlist have no AD, AS, PD, PS, etc., but do in the simulation netlist. >You also could simply make the caps >sequentially larger, but I know you wouldn't do that because of [quoted text clipped - 4 lines] >instances, I've also created these arrays by adding the appropriate >instance name on the device. C[0:31] I can do that too, but generally limit such notation to buses. >Regards, >Larry > >"nutcase" I presume you mean, by "nutcase", that you've never really used a good simulator ;-) ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >>dg, You harp about things that you know not about. LTSpice can run >>ANY netlist... you're just too much the amateur to understand how. For completeness, I suppose I should include an example of the resistor error messages when the resistor is specified with w/l and a model. LTspice is apparently looking for the original spice syntax for the various parameters in the model and doesn't utilize much of the foundry supplied resistor model. The fact that it works for "semiconductor resistors" is not documented: Syntax: Rxxx n1 n2 <value> [tc=tc1, tc2, ...] The resistor supplies a simple linear resistance between nodes n1 and n2. A temperature dependence can be defined for each resistor instance with the parameter tc. The resistance, R, at will be R = R0 * (1. + dt * tc1 + dt**2 * tc2 + dt**3 * tc3 + ...) where R0 is the resistance at the nominal temperature and dt is the difference between the resistor's temperature and the nominal temperature. Running this file shows the error messages the simulator kicks out. It does find the sheet resistance and that provides an accurate nominal simulation in the rc below: LTSPICE test V1 1 0 pulse(0 5 10u 1n 1n 1) R1 1 2 1e4 C1 2 0 1e-9 XR2 1 3 rny10k C3 3 0 1e-9 .SUBCKT RNY10K a b RR10 N_1 b NY W=4.4U L=88U RR9 N_2 N_1 NY W=4.4U L=88U RR8 N_3 N_2 NY W=4.4U L=88U RR7 N_4 N_3 NY W=4.4U L=88U RR6 N_5 N_4 NY W=4.4U L=88U RR5 N_6 N_5 NY W=4.4U L=88U RR4 N_7 N_6 NY W=4.4U L=88U RR3 N_8 N_7 NY W=4.4U L=88U RR2 N_9 N_8 NY W=4.4U L=88U RR1 a N_9 NY W=4.4U L=88U .ENDS RNY10K .tran 1u 0.1m .model ny r rsh = 50 + dw = 0.08e-6 dlr = -0.8e-6 + cox = 1.3e-4 capsw = 0.060e-9 + tc1r = 4.0e-4 tc2r = 1.1e-6 + tref = 25 * .end Again, this works fine in Smartspice. No subcircuits needed :-) Regards, Larry >>>dg, You harp about things that you know not about. LTSpice can run >>>ANY netlist... you're just too much the amateur to understand how. [quoted text clipped - 61 lines] >Regards, >Larry Take it up with Mikey. You've wasted several hours of my time. No more. Fookin' amateur ;-) ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. >Take it up with Mikey. You've wasted several hours of my time. No >more. Fookin' amateur ;-) > > ...Jim Thompson To JIM: Take your lithium. Rent Napoleon Dynamite. Grab a good cabernet and enjoy life :-) You may want to reconsider saying things like this to others - "You harp about things that you know not about". I was curious at that point what you might actually know. Not curious now. :-) TO THE GROUP: Hopefully the exchange might provide some insight to others on the various topics and wasn't too distracting. If so, let me apologize. Sorry for taking over the thread. I had fun though. :-) Regards, Larry >>Take it up with Mikey. You've wasted several hours of my time. No >>more. Fookin' amateur ;-) [quoted text clipped - 21 lines] >Regards, >Larry Bwahahahahaha! Fookin' amateur! Though I'm a Scot, not Irish, I like that phrase "Fookin' amateur"; have to add it to my repertoire ;-) ...Jim Thompson | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | | http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food. [...] >Ltspice really does run well under wine. I was impressed. I didn't >do benchmarks, so have no way of knowing at this point how the extra >overhead might affect a long simulation. I think you will find that the extra overhead of running it under Windows (at least Win98) makes it run only a little slower than it does using wine. Is this what you mean? [...] >arranged them differently? If true it makes one wonder if the word >duh means anything to these folks. Then again, why is it some vendors >seem to be able to write distro independent software for linux and >while others can't? Some companies have good programmers and others don't. In some cases, it isn't that the software will not work just fine on some other system, it just that the maker only tests it on one version and makes their install script test for that specific version. I use SuSE to run "dosemu" to run the DOS Orcad. I had troubles with DOS orcad running dos windows on Windows machines. So far there has been no problem under dosemu. Unlike windows, xdosemu allows the DOS window to be resized etc.  Signature-- kensmith@rahul.net forging knowledge >[...] >>Ltspice really does run well under wine. I was impressed. I didn't [quoted text clipped - 4 lines] >(at least Win98) makes it run only a little slower than it does using >wine. Is this what you mean? Actually, I was wondering how wine itself works as an emulator. I'm supposing it adds another layer between the application and the hardware and would incur some overhead. Is this not the case? I sometimes find I have to run sims that take days. In these cases, speed counts. >[...] >>arranged them differently? If true it makes one wonder if the word [quoted text clipped - 6 lines] >just that the maker only tests it on one version and makes their install >script test for that specific version. So you have to solve the problem caused by the various distro vendors by writing different install scripts? I believe there actually is an attempt to solve this problem by normalizing the libraries so 3rd party software can always find them. This seems like a better solution, but so far the various vendors haven't complied. Redhat probably thinks their user base is "captured" by the way they have these libraries arranged. The other vendors apparently refuse to follow Redhat. >I use SuSE to run "dosemu" to run the DOS Orcad. I had troubles with DOS >orcad running dos windows on Windows machines. So far there has been no >problem under dosemu. Unlike windows, xdosemu allows the DOS window to be >resized etc. I'll have to look at this - thanks! One of the issues with switching to linux is that 3rd party software vendors seem to not want to port their code to it. Nero did recently and has been taking flack because their code is proprietary. If the linux community wants linux to grow, they should encourage such things. It also means they should take steps to ensure easy operability between distros I think. So far I've tried Fedora, Xandros, and SuSE. SuSE seemed to set up the hardware more easily, though Xandros was also very good. Using a memory stick on Fedora meant creating a special mount directory and going through that process. SuSE and Xandros seemed to just recognize a memory stick automatically. Only Xandros automatically set up Samba so that it would function on my lan with win2k machines. Regards, Larry >>[...] >> [quoted text clipped - 7 lines] > > Actually, I was wondering how wine itself works as an emulator. The acronym for Wine is: <W>ine <I>s <N>ot an <E>mulator Wine is an applications interface for windows code that runs under x86 based linux systems. Just like 'doze 98 is an applications interface for windows code that runs under DOS. I'm > supposing it adds another layer between the application and the > hardware and would incur some overhead. Is this not the case? No more so than the layer between windoes and dos. The underlying operating system, linux, is a whole bunch more efficient than the windows/dos mess. -Chuck >> Actually, I was wondering how wine itself works as an emulator. > >The acronym for Wine is: <W>ine <I>s <N>ot an <E>mulator Ha! Good to know ... :-) There must be a lot of booze and good natured humor coming up with some of these names. >Wine is an applications interface for windows code that runs under >x86 based linux systems. Just like 'doze 98 is an applications [quoted text clipped - 7 lines] >operating system, linux, is a whole bunch more efficient than the >windows/dos mess. I'm hoping to transition to linux on all my machines, but first I guess I have to jump through the Redhat hoop. Thanks for the info! Regards, Larry [....] >Actually, I was wondering how wine itself works as an emulator. Wine works very well indeed as an emulator even though it is in fact not an emulator but a port of the windows API onto linux. > I'm >supposing it adds another layer between the application and the >hardware and would incur some overhead. Is this not the case? Consider the case of a request to write to a file: The typical Windows application does this: (1) The object that is requesting to be written calls its virtual method that is used for writing. (2) The write virtual method calls the virtual method for each of its component parts. (3) Each component part calls the virtual method that is part of the file handling stuff in MFC. (4) The file handling stuff creates the needed structure to pass to the windows API. (5) The windows API recieves the request and burries it in warm peat for aging. (6) The windows API hands the request to the 32 bit DOS function. (7) The 32 bit DOS function calls the section of the device driver that does writing (8) The device driver waits for the tubes in the disk drive to warm up and then dribbles the data into the srive. Under wine, items 5 to 8 change to this: (5) The wine code recieves the request. (6) wine passes the request to the kernal function (7) The kernal transfers the data to a buffer and flags it as needing to be written. (8) When time permits or there are not enough buffers left, the Kernal calls the code for writing on this type of disk. (9) The write actually happens. >>Some companies have good programmers and others don't. In some cases, it >>isn't that the software will not work just fine on some other system, it [quoted text clipped - 3 lines] >So you have to solve the problem caused by the various distro vendors >by writing different install scripts? In many cases, it is just a matter of using the software from the good programmers and ignoring the software from the bad ones. > I believe there actually is an >attempt to solve this problem by normalizing the libraries so 3rd >party software can always find them. It is less about normalizing and more about picking a minimum standard and going with that. <RANT> Bad programmers assume that the target machine has all the latest stuff. Good programmers only enforce the requirements that actually matter in their code. Bad programmers hard code the locations and versions of everything. Good programmers allow for things to be specified at install time. <\RANT> > This seems like a better >solution, but so far the various vendors haven't complied. Redhat >probably thinks their user base is "captured" by the way they have >these libraries arranged. The other vendors apparently refuse to >follow Redhat. Dead Rat has lots of silly ideas. But then so do lots of other folks. Altera just brought out a version of Quartus that runs under Linux, if you have the right version of Read Hat and if you have the right version of QT and if you have the right version of Glibc and if you place your left hand on top of your head while you install it. All Quartus really is, is a compiler and a text editor. They could have left the editor out. There is no reason a compiler needs any such specifics about the machine it will run on. [...] >One of the issues with switching to linux is that 3rd party software >vendors seem to not want to port their code to it. Nero did recently >and has been taking flack because their code is proprietary. If the >linux community wants linux to grow, they should encourage such >things. It also means they should take steps to ensure easy >operability between distros I think. Nero comes free with many DVD burners etc. The free version is not the Linux version. I think this is why they are getting flack. If they gave you the Linux version when you bought the DVD burner, most users would not care that they did not get the source code. [...] >So far I've tried Fedora, Xandros, and SuSE. SuSE seemed to set up >the hardware more easily, though Xandros was also very good. Using a >memory stick on Fedora meant creating a special mount directory and >going through that process. SuSE and Xandros seemed to just recognize >a memory stick automatically. Only Xandros automatically set up Samba >so that it would function on my lan with win2k machines. My work machine runs SuSE 9.2. It almost got samba right on the first try. At home I run SuSE 8.2. The samba set up in it was completely broken. There are signs of progress. Signature-- kensmith@rahul.net forging knowledge >[....] >>Actually, I was wondering how wine itself works as an emulator. [quoted text clipped - 113 lines] >try. At home I run SuSE 8.2. The samba set up in it was completely >broken. There are signs of progress. Thanks for the thoughtful reply! Regards, Larry >Some companies have good programmers and others don't. In some cases, it >isn't that the software will not work just fine on some other system, it >just that the maker only tests it on one version and makes their install >script test for that specific version Btw, this is the linux file system standard I believe they're trying to implement: http://www.pathname.com/fhs/ Regards, Larry |
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