LTSpice is a version of SPICE from Linear Technology

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LTSpice AD736 simulation problem

I'm trying to simulate some circuit with AD736 (RMS to DC converter). Datasheet: http://www.analog.com/media/en/technical-documentation/data-sheets/AD736.pdf You can check my attached schematic - ...
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Lt Spice Simulation

I intended to simulate and find out the operating Point of an npn transistor in Lt Spice. Even after trying a lot I am unable to get the desired results. Can anyone please help me with simulating the ...
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30 views

Problem with simulating LC filter with N channel MOSFET used for PWM

I'm trying to simulate an LC filter for a PWM output and I'm having problems with MOSFET used for controlling the voltage. I'm using LTSpice for simulation. When I filter the PWM output directly, it ...
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38 views

syntax error function if() requires exactly 3 arguments in ltspice what is the error

syntax error function if() requires exactly 3 arguments in Lt spice what is the error i am using the following net list for my sub circuit ...
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31 views

Help with LTSpice!

Im simulating a circuit for my electronics lab and was wondering how can I put a voltage at the end of a wire like in the picture?
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26 views

LTSpice Measurement on Plot

I am modeling different circuits in LTSpice and I cannot for the life of me find ways to annotate the plots with measurements. How can I perform simple measurements such as measuring 3dB points, max ...
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39 views

Is there a database on internet for LTspice models?

LTSpice doesn't have many components as default. One has to download the spesific model component and integrate it. Is there a website where I can look for it?
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53 views

How do I model a charge source in SPICE?

I would like to model a force sensor based on a piezoelectric crystal that generates 10pC/N and has a static capacitance of 20pF in LTSpice for simulation purposes. How can I do this?
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23 views

TABLE to .param TABLE

Until now I use TABLE parameters only directly in a Symbol. This is particular for long tables not easily readable. How can I do this over an indirection like shown right hand in the image? ...
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98 views

power supply oscillates when loaded with instrumentation amp

I've been working on an instrumentation amplifier for a PWL ECG signal in LTSPICE. It should be able to filter out the common mode noise. I Also need to design a power supply. Both the power supply ...
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39 views

Convergence problem in pspice but not in ltspice

I am trying to simulate a circuit in LTSPICE and it simulates without any convergence problems. However when I copy the netlist into pspice and try it simulate it I get strange results. It keeps ...
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47 views

LTspice: Vary a capacitor's value over time

I want to vary a capacitor's value over time. A previous question (LTspice: Vary a resistor's value over time) asked how to vary a resistor's value over time. One of the answers was to use a ...
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32 views

modeling AC resistance proximity and skin effect using LTSPICE

I'm designing an air-core loop receiving antenna from <1Hz - 50kHz. Is there a way to approximately model the skin/proximity effect using lumped circuit parameters in SPICE software? I think you ...
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45 views

When I run the schemetic in LTSPICE,waves don't change direction.Why aren't waves changing direction here?

What pulse should I set to produce a waveform like in the graph?
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49 views

Why isn't current through D2 0 in LTSPICE?

The current through d2 should b zero as it is reverse biased. Why dosen't ltspice software show zero current? - If I am doing somethin wrong then kindly make correction and tell me what to do to ...
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186 views

AC/DC wall adaptor as LTSpice Analog behavior model (ABM)

Suppose a circuit shuld be supplied ( in real life ) from a wall mount AC/DC adaptor. The adaptor has a nominal voltage of 12VDC 500mA. With no load the adapter puts out 21.6V. After some measurement ...
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55 views

Help Converting a PSPICE MOSFET .LIB to an LTSPICE .SUB

I am designing a buck-boost regulator for a course at school and I would like to use the OnSemi ntk3139p PMOS transistor. OnSemi provides a few spice models for this part and I am getting stuck ...
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36 views

LTSpice parameter sweep of multiple values

I have designed a boost converter for my power electronics class in LTSpice. The thing works just fine, now all I have to do it fiddle with the component values and frequency to describe the trends I ...
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23 views

Simulation of ic1 Bel 1895 in LT spice

I am doing an electronics project on condenser mic audio amplifier. And for this I want to first simulate the circuit in lt spice.But I am not getting how to simulate ic1 bel 1895 on lt spice? Can ...
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40 views

Power feeder current and LTSpice simulation

I'm trying to develop a power feeder as already state in question Power feeder scheme adaptation. I have done some adjustments, now my circuit is The voltage regulator is an LM317. Since I have to ...
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72 views

LTspice MOSFET width sweep

I am trying to simulate the transfer characteristics of a CMOS inverter using LTspice. I want to sweep the MOSFET width and length and observe the effects on rise and fall times of the CMOS inverter. ...
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77 views

Where to get PSPICE models of ceramic resonators?

I wish to design and simulate IF filters using ceramic resonators and crystal oscillators in OrCAD Capture or LT SPICE. The default libraries don't have any ceramics, so anyone know where to download ...
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58 views

How to run new .meas commands without having to rerun the whole ltspice simulation?

I am trying to analyze a circuits properties over a certain range of component values, e.g. a PWM circuit for various settings of the control pot. For this I create a bunch of ...
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53 views

DC Motor inertia voltage drop

following a tutorial on the web I created in LTSpice a DC motor model, but I have a question about the results, the model is: and this is the spice netlist: ...
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109 views

LTSpice showing negative transistor power

I'm using LTSpice to model a LC oscillator, driven by a NPN transistor. When I used the power calculating function on the transistor, LTSpice indicated that during part of the cycle the power ...
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126 views

Calculation in LTspice “never” finishes

I'm currently using LTspice, and I have a problem with it "never" finishing calculating a certain circuit. When I say "never", I mean that it's still calculating an hour after it stated, even though ...
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263 views

How to calculate a circuits efficiency with the help of LTspice

Note that this is not a question for circuit critique (and lots of things could be said about this circuit) but this circuit is only the base for the discussion of further points. Here it is (an ...
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123 views

LTSpice missing an SSR Component?

I want to simulate some circuits with SSR component but LTSpice does not provide this. From Eagle and KiCad I learned I can create my own component diagram. I'm not sure if I can do this also with a ...
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253 views

IR2110 LTspice simulation weird behaviour

I am obtaining weird voltage behaviour at the gate of my high side mosfet controlled by IR2110 which is controlled by PWM. PWM configuration: Vinitial = 0 Von = 5v Tdelay = 0 Trise = 7u Tfall = 7u ...
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139 views

How to plot the frequency response of transconductance of BJT with LTSpice

I need to plot the frequency response of the transconductance of this circuit in the picture with LTSpice but I don't know how. Can you please help me urgently how should I do it? Thanks
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73 views

How to plot sliding average in ltspice?

I would like to plot a sliding average of some voltages and currents. Ideally I would just add a new trace with some expression, but all expressions that I found so far only operate on single values. ...
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106 views

Problem simulating a fixed transconductor with LTSpice

I am simulating a fixed transconductor circuit with LTSpice. When I apply \$1\$V for input voltage, (for DC Sweep) the voltage of collector of \$Q_1\$ has good amplitude (\$30\$mV to \$330\$mV) while ...
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95 views

Add permanent component in LTSpice from asc and asy

I'm trying to add a new permanent component (ULN2803) to LTSpice, having asc and asy files. I have read some tutorials in the web but focused on .lib and .sub files. How can I add the component from ...
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157 views

How reliable or trustworthy are LTSPICE demo circuits?

I'm looking at a few switching power supplies and one of the demo .asc files for the particular controller I was looking at really seems to fit my requirements. Can I use their schematics in designs ...
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703 views

Parts tolerance simulations in ltspice

I just recently found this tutorial (and various other places mentioning a similar technique) when trying to evaluate how one of my circuits behaves when using real world components with real world ...
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Inverse Nyquist Plot (damping factor) in LTSpice possible?

Looking forward to plot inverse Nyquist A11 (damping factor). So the inverse of the transfer function. Is it possible with LTSpice? Ps: Transfer 1/A11 Nyquists are no problem.
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How is Waveform Compression used in LTSpice to determine Timestep?

The LTspice wiki says (and I believe this is basically copy pasted from the offical documentation): Syntax: ...
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134 views

LTspice: Noise simulation AND AC analysis in one plot

Is it possible to run a noise simulation and an AC simulation independently from one another and display the results in the same plot? Or better, is there a way to determine the SNR in one single ...
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57 views

asymmetric supply voltage for an OP AMP

I'm trying to amplify a signal with the bandwith of 500Hz - 10Khz, to do that I'm the circuit in LTspice using an asymmetric supply for the OP : the resistance R5 is just to keep things ...
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136 views

Stepped Sine Wave in Spice

I'm interested in simulating a circuit using a stepped sine wave input. I want to sample a sine wave at regular intervals and have the output constant during each interval, making an output that looks ...
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Are the stock transistor models in LTspice accurate at RF?

Just checking, I'm doing some experimenting of small signal RF design in LTspice.
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Creating an adjustable output regulator, in LTspice

Firstly, I'm having some trouble with simulating a variable resistor in LTspice.. I am wondering if this can be done? Also, does anyone have any advice on how to theoretically analyse this circuit? I ...
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408 views

How to use .step param with more than two parameters in LTSpiceIV

I need to do three transient simulations with different values of certain resistors (conveniently called R1 and R2) in each. What I mean to do exactly is this: Sim. 1: R1 = 1 k\$\Omega\$, R2 = 10 ...
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Designing a Filter

I am trying to design a filter which has the following Bode plot, So according to this site I designed the filter as shown below, As the two cross over frequencies are f1 = 50 Hz and f2 = 200 ...
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148 views

How to design a SPICE model from data sheet?

I am new to SPICE simulation and I am looking for spice model file of LTC 1065 data sheet can be found here here. I searched a lot on Google but I could not find ...
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633 views

Is there a spice directive to export waveform data in LTspice?

http://www.linear.com/solutions/1815 The above web-page explains how to export the waveform data to a text file. You basically run the LTspice simulation, clicking on the waveform window, go to ...
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25 views

How do I specify a parameter for a specific component in LTSpice?

I have a schematic which uses two center-tapped transformers. I found that I can specify the ratio between the two sides of the transformer by adding the directive ".param ratioT=0.3". Now that I ...
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910 views

Importing 3rd Party Models into LTSpice

I'm new to LTSpice but have the basics figured out (laying out a schematic, setting up simulation, running) and have done so with the basic but very well stocked library included. Of course my issue ...
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168 views

Cross-conducting half-bridge

I attached an LTspice schematic, a very simplified version of a MOSFET half-bridge driven by a push-pull isolated signal transformer. The FETs are cross-conducting, but their gate pulses are not ...
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Viewing netlist on native ltspice for mac

I have a mac os x 10.9.3 and I run the native ltspice on it. I cannot seem to access the netlist (the text file version of the schematic) on it. Looking at the website: ...