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Questions tagged [ltspice]

Anything related to LTspice. LTspice is a SPICE simulation, schematic capture, and waveform viewer program from Linear Technology. LTspice is freeware with a very liberal license, it is lightweight, and isn't crippled in any way.

Anything related to LTspice. LTspice is a SPICE simulation, schematic capture, and waveform viewer program from Linear Technology.

LTspice is completely free and has no limitations (no maximum number of parts, for example, like the free crippled versions of other commercial simulators). It is one of the best simulators around (it is used by Linear Technology for in-house simulations - it is no toy). The program is lightweight (~40 MB installed), works under Windows, and was developed to be run in Linux under WINE. The license is very liberal: you can even use it for commercial purposes without permission from Linear Technology, as long as you are not a competitor in the market of chip design and manufacturing.

See also:

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How do you simulate voltage noise with LTSpice?

Is there a way to setup a voltage supply with voltage jitter/noise? I want to experiment with filtering out noise on various voltages etc. but not sure how to configure LTSpice to create a noisy voltage supply.
josef.van.niekerk
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LTspice: Vary a resistor's value over time

I want to simulate the load regulation of a power-supply. I'm sure I remember being able to vary the value of a resistor over the course of a simulation in LTspice, but I can't remember how. Anyone?
volting
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How to view and customize beta of a transistor in LTspice

If I need to set beta to a custom value, is it possible to make a customized transistor with a beta of my choice? In other words, can I edit a ready or generic transistor's beta and save it as a custom transistor? How can I do that?
user1245
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LTspice automation

I have a battery-powered boost converter and I'm attempting to measure the maximum input (battery) voltage droop under various load conditions of high current draws (different duty-cycles/periodicities) in addition to over several battery types…
Joel B
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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 k\$\Omega\$ Sim. 2: R1 = 1 M\$\Omega\$, R2 = 10…
sebascarra
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LTspice fails at a simple two-resistor voltage divider. How can I fix it?

During some simulations, I noticed some oddities and narrowed it down to the following problem: This is is simple voltage divider using two resistors. The four traces show: supply voltage current through R1. Everything is good so far the voltage…
tobalt
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Why does LTSpice say that my "Matrix is singular" for this ideal-transformer circuit?

I'm trying to do find the voltage over R1 in the following circuit, where L1/L2 is an ideal transformer. LTSpice complains that the "Matrix is singular". Why? I've tried to play around with lots of different values in order to see if it's a problem…
Karin
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Why doesn't LTSpice predict this op-amp oscillation?

I'm developing a circuit to act as an electronic load for bench testing power supplies. An earlier question about how to test this circuit received several very useful answers and can be found here: How to test op amp stability?. This question is…
scanny
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How to plot "voltage drop" across a specific component in LTSpice?

In the above circuit I can only be able to plot |Vr1+Vc1| = V1 in green plot and Vc1 in blue plot. I use the voltage probe in LTSpice and click on the lines to obtain the plots. If I click on the line between V1 and R1 it plots |Vr1+Vr2| = V1. If I…
user16307
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Why is my simple boost converter giving me such a high peak output voltage?

I am trying to understand switch-mode power supply fundamentals through a simulation in LTSpice. I wanted to build an excruciatingly simple boost converter circuit following a teaching model often given in textbooks, but I can't get this thing to…
Stephen Bosch
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LTspice sinusoidal voltage source with offset much larger than amplitude broken?

I've been troubleshooting an analog circuit and have just come to the realization that Sine Voltage sources at mV are broken. Here is one that is supposed to provide a 1mV 1Hz sine wave on top of a 300mV DC signal. Instead I get complete garbage.…
EasyOhm
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How to define the initial charge of a capacitor in SPICE

I would like to simulate a circuit with a capaciot in LTSPICE. In the first hand, I have tried to charge the capacitors in a period of time. However, the charging current is very high and I am not sure whether the capacitor will be completely…
Hamed
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LTSpice - Printing resultant parameters based on expressions

I'm designing a circuit but I'm computing the values of components based on a set of design values. For example, .param Vi=120 .param Po=100 .param Ro='(Vi*Vi)/(2*pi*pi*Po)' where Vi and Po are design parameters and Ro is being computed from the…
jkiv
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LTspice: simulating the bounce effect of a push button

I'm trying to reproduce in LTspice the switching response of a push button with bounce effect as shown on the second page of the SN015 Support Note by Würth Elektronik. Here is an excerpt: What I have tried to do is use two voltage-controlled…
noeld
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How can I convert PSpice model into LTSpice Model?

I would need to simulate these two MOSFETs ino LTSPICE but I have the Spice Model IPW65R019C7 Its PSpice model its insiede Nchannel CoolMos…
Fabio
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