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Re: dflops?
David,
I'm trying to use the dflop part in a simpleThere's some special things you need to know about the gates. The gates don't need external power. If you want a gate to switch between 0 and 5 volts, give the gate a value of "Vhigh=5" Vlow defaults to 0V. Also, all unconnected inputs are connected to the gate's common node(that extra pin that is tied to ground in the examples). This connection flags that pin as unused and is removed from the simulation. Note that the common pin will be connected to ground by the netlister if it is left floating. So, say you place an AND gate on the schematic, connect one of it's input to a signal, one input to ground and leave the other 3 inputs floating. The AND's output will follow the signal because all the other pins aren't floating or grounded, but flagged as not part of the simulation. --Mike __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! |
dflops?
David Pariseau
I'm trying to use the dflop part in a simple
circuit and am having difficulty getting it to work. +-----------+ 0-6v square wave --------|>CLK Q |--- 1v solid out?? GND----| D Q'| +-----------+ Both the CLR and the PRE inputs are floating though I've tried tieing them up and down. There doesn't seem to be anywhere to attach power to the device? There is a common pin (COM?) on the corner, but leaving it open or tieing it to ground has the same effect. I'm looking for a 5-6v output. The 160 example has dflops in it and seems to work fine, which is beyond me. Any ideas? Thanks, David Pariseau. |
Re: New Feature Released & Opamp Modeling
Jon,
...For example, if I select 2N6028 in the drop-downYou probably want to make the Model and Instance name visible in the .asy file and nothing else. THE VALUE SHOULD BE LEFT BLANK in both the .asy and instance, unless you want to add parameters to pass to the subckt. These should be of the form "eta=5.3" Attached is a .asy file and .sub file that work together to demonstate being able to use the drop list to to select a subckt in the .sub file. You will have to fix line wrap. --- .asy --- Version 4 SymbolType CELL LINE Normal -32 -32 32 0 LINE Normal -32 32 32 0 LINE Normal -32 -32 -32 32 LINE Normal -28 -16 -20 -16 LINE Normal -28 16 -20 16 LINE Normal -24 20 -24 12 LINE Normal 0 -32 0 -16 LINE Normal 0 32 0 16 LINE Normal 4 -20 12 -20 LINE Normal 8 -24 8 -16 LINE Normal 4 20 12 20 WINDOW 0 16 -32 Left 0 WINDOW 38 47 28 Center 0 SYMATTR Prefix X SYMATTR Description Parameterized Single Pole Opamp. En and in are equivalent voltage and current noises. Enk and ink are the respective corner frequencies. SYMATTR Value2 Avol=10Meg GBW=10Meg Slew=10Meg SYMATTR SpiceLine ilimit=25m rail=0 Vos=0 SYMATTR SpiceLine2 en=0 enk=0 in=0 ink=0 SYMATTR ModelFile genopamp.sub SYMATTR SpiceModel 1pole PIN -32 16 NONE 0 PINATTR PinName In+ PINATTR SpiceOrder 1 PIN -32 -16 NONE 0 PINATTR PinName In- PINATTR SpiceOrder 2 PIN 0 -32 NONE 0 PINATTR PinName V+ PINATTR SpiceOrder 3 PIN 0 32 NONE 0 PINATTR PinName V- PINATTR SpiceOrder 4 PIN 32 0 NONE 0 PINATTR PinName OUT PINATTR SpiceOrder 5 --- .sub --- * Copyright Linear Technology Corp. 1998, 1999, 2000, 2001, 2002, 2003. All rights reserved. * .subckt 1pole 1 2 3 4 5 S1 5 3 N002 5 Q S2 4 5 5 N002 Q A1 2 1 0 0 0 0 N002 0 OTA G={Avol/Rout} ref={Vos} Iout={slew*Cout} Cout={Cout} en={en} enk={enk} in={in} ink={ink} Vhigh=1e308 Vlow=-1e308 C3 5 4 1p C4 3 5 1p S3 N002 0 4 N002 C S4 0 N002 N002 3 C R2 N002 4 {2*Rout} noiseless R1 3 N002 {2*Rout} noiseless R3 3 1 1G noiseless R4 3 2 1G noiseless R5 2 4 1G noiseless R6 1 4 1G noiseless .model C SW(Ron=100 Roff=1T Vt=0 Vh=-1 noiseless) .param Rout=100Meg .param Cout={Avol/GBW/2/pi/Rout} .model Q SW(Ron=10 Roff=10Meg Vt=0 Vh=-.1 Vser={Rail} ilimit={Ilimit} noiseless) .param Avol=10Meg GBW=10Meg Slew=10Meg ilimit=25m rail=0 Vos=0 .param en=0 enk=0 in=0 ink=0 .ends 1pole .subckt 2pole 1 2 3 4 5 S1 5 3 N002 5 Q S2 4 5 5 N002 Q A1 2 1 0 0 0 0 N003 0 OTA G={Avol/Rout} ref={Vos} Iout={slew*Cout} Cout={Cout} en={en} enk={enk} in={in} ink={ink} Vhigh=1e308 Vlow=-1e308 Rout={Rout} C3 5 4 1p C4 3 5 1p S3 N002 0 4 N002 C S4 0 N002 N002 3 C R3 3 2 1G noiseless G1 0 N002 N003 0 {1/Rout} R1 3 N002 {2*Rout} noiseless R2 N002 4 {2*Rout} noiseless C1 N002 0 {X*Cout/Avol} S5 0 N003 N003 3 C S6 N003 0 4 N003 C R4 3 1 1G noiseless R5 1 4 1G noiseless R6 2 4 1G noiseless .model C SW(Ron=100 Roff=1T Vt=0 Vh=-1 noiseless) .param Rout=100Meg .param Cout={Avol/GBW/2/pi/Rout} .model Q SW(Ron=10 Roff=10Meg Vt=0 Vh=-.1 Vser={Rail} ilimit={Ilimit} noiseless) .param Avol=10Meg GBW=10Meg Slew=10Meg rail=0 Vos=0 ilimit=25m .param en=0 enk=0 in=0 ink=0 phimargin=45 .param X table(phimargin,29.4,3.5,32.1,2.9,33.8,2.6,35.8,2.3,38.1,2,40.9,1.7,43.2,1.5,45.9,1.3,49.2,1.1,53.2,0.9,58.2,0.7,64.7,0.5,73,0.3,86.1,0.05) .ends 2pole __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! |
Re: New Feature Released & Opamp Modeling
Jonathan Kirwan
On Wed, 26 Mar 2003 00:49:55 -0800, you wrote:
Thanks. Just tested and it seems to work okay. Now what I'mI guess I'm asking this because the .ASY I currently use automatically displays the Value attribute. But the new drop-down for the SpiceModel only changes the SpiceModel attribute (perhaps, as it should.) Since this isn't normally displayed on the schematic, so far as I've seen anyway, selecting a new model doesn't change what appears on the schematic. So I have to manually change the Value attribute, as well, in order to match (so it appears.) For example, if I select 2N6028 in the drop-down for SpiceModel *and* then manually change the Value attribute to match, everything works well. If I then set the Value attribute to "junk," leaving the SpiceModel to 2N6028, I get "Error: Unknown subckt called in: xu1 n001 n002 n003 2N6028 junk" If I then try and change the Value attribute to 2N6027 (which is also present in the .LIB file I have, but which is *not* a match for the current SpiceModel, which is 2N6028), then I get the error, "Too many parameters for subcircuit type "2n6027" (instance: xu1)" Just to let you know. Jon |
Re: New Feature Released & Opamp Modeling
Jonathan Kirwan
On Tue, 25 Mar 2003 15:19:26 -0800 (PST), you wrote:
Jon,Thanks. Just tested and it seems to work okay. Now what I'mIn the above case, it would be nice if LT SpiceYes, this is something that's been needed for a wondering about is what is displayed on the schematic. Should I remove "visibility" for the Value attribute and add "visibility" for the SpiceModel attribute on the underlying .ASY symbol? Jon |
Suggestions for waveform viewer
Schaich, Peter
Hi there, |
Re: Adding 3rd party Mosfet
--- In LTspice@..., "David Pariseau"
<david.pariseau@s...> wrote: Helmut,Hello Dave, sorry, but YAHOO shorted my e-mail address so that you had no chance to fully read it. HelmutSennewald"at"t-online.de Replace "at" with @. You can use my Yahoo address too, if it still doesn't work. HelmutSennewald@... Best Regards, Helmut |
TRIAC model
Hello,
I'm new to this group and I don't have experience working with Spice models. Someone can please help me or point me to the right direction so I can make a TRIAC model? If there's some ready-to-go model, please let me know. Thank you very much, Brusque -- ----------------------------------------------------------------- Edson Brusque C.I.Tronics Lighting Designers Ltda Research and Development Blumenau - SC - Brazil Say NO to HTML mail www.citronics.com.br ----------------------------------------------------------------- |
Re: Using Field Sync about the Globe
There's been some reorganization of
the website that I use of SwCADIII/LTspice publication. Could you folks let me know if the menu item Tools=>Sync Release works for you. It should work from anywhere in the world and give you version 2.01s right now. Probably better to e-mail me at pmte@..., instead of posting to the users' group. --Mike __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! |
Re: Adding 3rd party Mosfet
Helmut,
Hello Mike or whoever exactly knows about,Yes you are correct, node 0 is global. Even if used in a subcircuit, it is global ground. You can't name the pin of a hierarchical symbol "0" and have that refer to the node "0" inside that page of circuitry. Note that you can specify other nodes to be globals with the .global dot command. --Mike __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! |
Re: Setting or Freezing Plot Scales
Steve,
First let me congratulate the author(s) and thoseThanks! My daughter, who is an engineering sophomore,Cool. Just the same, I don't think we should risk having a slogan like, "So easy to use even girls can use it." I am looking for a way to either pass plot scalesYes, I we will be making it possible to have named plot setups and turn off autoscaling. I was planing on starting that today, but this programmable library became important because it changes some standards used. --Mike __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! |
Re: New Feature Released & Opamp Modeling
Jon,
In the above case, it would be nice if LT SpiceYes, this is something that's been needed for a long time. So I implemented it today. To use it make a symbol with prefix 'X'. Make ModelFile point to a library contianing subcircuits. Give the symbol a SpiceModel that coincides with the name of a subcircuit in ModelFile. Those conditions will cause the editor for the SpiceModel to be replaced with a drop list of subcircuits in the file pointed to by ModelFile. I modified the symbols 1pole.asy and 2pole.asy to put the subcircuit names as the SpiceModel attribute instead of the value so that you can see it work(Though there's only one subcircuit in the list to choose from). It's possible that old schematics drafted with yesterday's version don't work, just delete and replace the 1pole and 2pole instances to fix. --Mike __________________________________________________ Do you Yahoo!? Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop! |
Re: Adding 3rd party Mosfet
--- In LTspice@..., "David Pariseau"
<david.pariseau@s...> wrote: yourHello Dave, errorssymbol. You can see that requirement in the model file. I triedThat's weird, the part is in an SOT-3 package w/ only 3 pins, now in simulation, but the simulation is glacially slow and I'm notHello David, you can send me your circuit file(s) for testing. Please use the following e-mail address if you are interested. HelmutSennewald@... Best Regards Helmut |
Re: Adding 3rd party Mosfet
David Pariseau
Hello Dave,That's weird, the part is in an SOT-3 package w/ only 3 pins, but it seems that the 4th input is temperature??? It has been also necessary to add a resistor to this additionallyI added this and commented out the Diode line and there are no errors now in simulation, but the simulation is glacially slow and I'm not sure correct. Thanks for the input, Helmut, Dave Pariseau. |
Re: Adding 3rd party Mosfet
--- In LTspice@..., "David Pariseau"
<david.pariseau@s...> wrote: I've read through past messages, the SwCAD help Hello Dave, this model from Fairchild has 4 pins. Please add a 4th pin to your symbol. You can see that requirement in the model file. I tried this with success. *20=DRAIN 10=GATE 30=SOURCE 50=VTEMP .SUBCKT FDN304p 20 10 30 50 It has been also necessary to add a resistor to this additionally node in the schematic. I connected a 1k resistor to ground in my test circuit. This works at least for circuits where the drain is connected to >=0V. Fairchilds fault? The model has a badly designed breakdown section. It shorts the drain if it is below zero volt relative to ground. So it is unusable in this case. If you have a need for this then you can comment the line with the diode D. *D DB1 20 DBLK Now it will run with a voltage below 0V too, but the breakdown is no more modelled. Original section: *DIODE THERMO BREAKDOWN SECTION EBL VB1 VB2 101 0 0.8 VBLK VB2 0 20 D DB1 20 DBLK .MODEL DBLK D(IS=1E-14 CJO=.1p RS=.1) EDB 0 DB1 VB1 0 1 Hello Mike or whoever exactly knows about, if a model uses the node number 0, is it then referenced to the common ground 0 of the top schematic or is this a floating node like any other node inside the subcircuit? Best Regards Helmut |
Re: New Feature Released & Opamp Modeling
cadencespectre
--- In LTspice@..., "Reinier Gerritsen" <r.gerritsen@c...>
wrote: SNIP - a way to store multiple analysis commands. If I use .tran and .acgets lost on exit of the program.Hoi Reinier, It is possible to save multiple analysis commands. First place a simulation command on the sheet. When you add a second simulation command with Simulate -> Edit Simulation Command (or right mouse button -> Edit Simulation Command), and place the command on the sheet, you'll see the "." in the first comman will change to ";". E.g. you'll get: .tran 10n ;ac dec 51 100 10G ;dc temp -40 125 2 If you save this schematic, and reopen it, you can choose using Simulate -> Edit Simulation Command (or right mouse button -> Edit Simulation Command). It only works for different analysis types. I.e. you can't choose between e.g. multiple .tran commands (however you can uncomment them). Of course you can place these lines on the schematic manually. Regards, Ronnie (Also from the Netherlands :-) ) |
Adding 3rd party Mosfet
David Pariseau
I've read through past messages, the SwCAD help
and such and attempted to add a 3rd party model for the FDN304P. It seems to find the model fine now, but I get the error "Too few parameters for subcircuit type "fdn304p"". I basically dropped the model file into the \sub directory, copied the pmos symbol file and changed it to specify the FDN304p model. Any thoughts? Dave Pariseau. Here are the files: FDN304p.asy ------------- Version 4 SymbolType CELL LINE Normal 48 48 48 96 LINE Normal 16 80 48 80 LINE Normal 16 48 24 48 LINE Normal 48 48 24 44 LINE Normal 48 48 24 52 LINE Normal 24 44 24 52 LINE Normal 16 8 16 24 LINE Normal 16 40 16 56 LINE Normal 16 72 16 88 LINE Normal 0 80 8 80 LINE Normal 8 16 8 80 LINE Normal 48 16 16 16 LINE Normal 48 0 48 16 WINDOW 0 56 32 Left 0 WINDOW 3 56 72 Left 0 SYMATTR Value FDN304P SYMATTR Prefix X SYMATTR SpiceModel FDN304P.mod SYMATTR Value2 FDN304P SYMATTR Description P-Channel MOSFET transistor PIN 48 0 NONE 0 PINATTR PinName D PINATTR SpiceOrder 1 PIN 0 80 NONE 0 PINATTR PinName G PINATTR SpiceOrder 2 PIN 48 96 NONE 0 PINATTR PinName S PINATTR SpiceOrder 3 FDN304p.mod --------------- *FDN304P at Temp. Electrical Model (T2) *------------------------------------- .SUBCKT FDN304p 20 10 30 50 *20=DRAIN 10=GATE 30=SOURCE 50=VTEMP Rg 10 11x 1 Rdu 12x 1 1u M1 2 1 4x 4x DMOS L=1u W=1u .MODEL DMOS PMOS(VTO=-0.87 KP=2.5E+1 +THETA=0.25 VMAX=8.5E5 LEVEL=3) Cgs 1 5x 1300p Rd 20 4 7E-3 Dds 4 5x DDS .MODEL DDS D(M=4.26E-1 VJ=3.39E-1 CJO=562p) Dbody 20 5x DBODY .MODEL DBODY D(IS=3.81E-10 N=1.145283 RS=0.00084 TT=14.5n) Ra 4 2 7E-3 Rs 5x 5 0.5m Ls 5 30 0.5n M2 1 8 6 6 INTER E2 8 6 4 1 2 .MODEL INTER PMOS(VTO=0 KP=10 LEVEL=1) Cgdmax 7 4 1050p Rcgd 7 4 10meg Dgd 4 6 DGD Rdgd 4 6 10meg .MODEL DGD D(M=3.2E-1 VJ=4.23E-3 CJO=1050p) M3 7 9 1 1 INTER E3 9 1 4 1 -2 *ZX SECTION EOUT 4x 6x poly(2) (1x,0) (3x,0) 0 0 0 0 1 FCOPY 0 3x VSENSE 1 RIN 1x 0 1G VSENSE 6x 5x 0 RREF 3x 0 10m *TEMP SECTION ED 101 0 VALUE {V(50,100)} VAMB 100 0 25 EKP 1x 0 101 0 .012 *VTO SECTION EVTO 102 0 101 0 .0007 EVT 11x 12x 102 0 1 *DIODE THERMO BREAKDOWN SECTION EBL VB1 VB2 101 0 0.8 VBLK VB2 0 20 D DB1 20 DBLK .MODEL DBLK D(IS=1E-14 CJO=.1p RS=.1) EDB 0 DB1 VB1 0 1 .ENDS FDN304p *FDN304P (Rev.A) 12/4/00 **ST |
Setting or Freezing Plot Scales
First let me congratulate the author(s) and those that support this
software. It is really useful and easy to use. My daughter, who is an engineeing sophmore, has even started to use LTSpice for some labs. I am looking for a way to either pass plot scales from a dot statement (.PLOT or .VIEW kind of thing) or at least to freeze the plot scales from run to run. It would be helpful when trying to visually compare the the results between runs if the the plot did not automatically rescale. It would also be nice to be able to have an alias type statement to save reentering things like V(out)/V(in) or V(N003, N006)/I(R7). Again, thank you for the software and thanks to Linear Tech for their part in this. |
Re: resistance values that depend on simulation time
Thanks for the quick reply. I figured there had to be a way to do
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this. I will give it a whirl. --Brent --- In LTspice@..., Panama Mike <panamatex@y...> wrote:
...But I need to model the time dependence of theseThere's an undocumented means to do this. You might |
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