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.
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LT6268-10 Opamp Oscillation and Offset
Below is my Photodiode-OpAmp circuit that is configured as Transimpedance Amplifier.
When I put both inverting and non inverting into ground, no signal is coming out. However when I connect ...
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Modelling power transfer under saturation for 1:N current transformer in LTspice
A toroidal current transformer consisting of two half-toroids with air gaps, is clamped around an overhead 50 Hz AC power line carrying 50-300 A (i.e. a 1:N CT). It is used for energy harvesting.
Is ...
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Help to configure an LTspice PLL simulation
I never tried PLLs before and to gain some insight I'm trying to simulate CD4046Bg in LTspice where I want the output to phase-lock and follow the input signal. I tried so far the below:
But I get an ...
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Import transistor into LTSpice
I would like to import this transistor -> RFD16N06LE (datasheet: https://www.alldatasheet.com/datasheet-pdf/pdf/67811/INTERSIL/RFD16N06LE.html) into LTSpice; the datasheet has a PSPICE model ...
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Decent MOSFET for a beginner to learn from?
I am relearning MOSFETs, but more importantly I would like to focus on building some basic circuits and learning practicality over theory. I have a BSEE but haven't spent much time outside of class on ...
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Where should I take the measurement from to find the correct attenuation level of a resistive pi attenuator?
I am currently designing a resistive attenuator for an RF project I'm working on. I wanted to have several resistance combinations to obtain various attenuation levels (1-8 dBs). When I calculate the ...
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Can this oscillator possibly work?
I am trying to build a crude RF oscillator. My first attempt, though it simulated fine, disappointingly did not oscillate when soldered together. So, to debug this, I reduced the simulation example ...
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How can I simulate an RF signal as received by an antenna in LTspice?
How can I simulate an RF signal as received by an antenna in LTspice?
I am designing a simple HF RF receiver and want to test it via LTspice. Can I simulate an RF signal as:
A pure voltage source, ...
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How soft start circuit works, LTspice simulation [closed]
Please help for the attached circuit, further explain how soft start circuit works in M2 (PMOS) with RC circuit, computation and the voltage divider with zener diode with BJT (PNP), how it works, for ...
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Why did I get different simulation results for the same transistor model in LTspice?
The following is my FM transmitter circuit. In the first simulation, I auto-generated a symbol for BFQ19S.
Replace the auto-generated symbol with the one from default NPN.
In the second simulation, ...
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Is there any way to speed up simulation in Ltspice? [closed]
The following is my FM transmitter circuit. It takes about 1 minute to simulate.
In real life, I want to use this BFQ19SH6327XTSA1 from Infineon instead of 2N22222. (link datasheet) and download link ...
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Beat frequency - Square signal
This question comes from this one, LTspice - Beat frequency:
It appears that when I did a FFT of two sinusoidal signals, there was no what is called beat frequency.
When I do the same exercice with ...
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Does the FFT in LTspice not work properly?
I wanted to do an FFT of a square signal in LTspice. Here is the simulation:
Here is the result of the FFT through R4:
There is no reason to have frequencies below 100 kHz according to theory. What ...
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LTspice - Beat frequency
Here is the theory from wikipedia:
Here are my summation of sin on LTspice:
The frequencies are 100 kHz and 120 kHz on the FFT. There is no frequencies at (f1+f2)/2 and no frequencies at (f1-f2)/2.
...
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Need help analyzing sability of op-amp in a current source in LTSpice
I have to perform stability analysis on an op-amp (AD8671) which is being used as an op-amp in the circuit attached. I am using LTSpice to perform this. My approach is to give a 1V AC small signal at ...
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I am Seeking Help to Adjust DC Motor Simulation Parameters in LTspice for Accurate Current Modeling
I'm relatively new to LTspice and motor diagnostics, but I have managed to build a PWM-MOSFET control circuit for a DC motor. My goal is to simulate this project to evaluate potential ripple currents ...
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LTspice simulating varying capacitance in cap-to-voltage simulation [closed]
I am interested in simulating the increasing output voltage and the end of this circuit when the parameter C1, changes according to a list of increasing capacitance values. So far I have managed to ...
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How does the leakage inductor distribute over multiple coupled inductors?
I am working in LTspice with a triple coupled magnetic inductor. I chose the factor of coupling to be 90%. L_1 is 1000uH so the uncoupled energy should be 100uH. How does the 100uH energy distribute ...
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Iterative Simulation LTspice Model using Python
I'm new to python. I have a python code to simulate my LTspice model. I need to change the on time in the pulse parameters and I need a large number of simulations for at least 100 different Ton. So I ...
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How to simulate a uniform distribution around zero in LTSpice?
I am using LTSpice for a Monte-Carlo simulation, I typically use the function {mc(x,y)} for componant variability
I also want to introduce spread in the feedback ...
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LTSpice old GUI schematic icons
This is about LTSpice version 24.0.12
How to get the hand symbol (move) back in new GUI? I would like the icon refer to something real worldy. A hand is used universally for moving things and current ...
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Pi-Filter Simulations Comparison
I am trying to simulate the filter impedances on LTspice. There are two images of the simulation results of the same pi-filter on LTspice and Redexpert. Although I am not sure the parameters are ...
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How can I determine how much power is in a frequency range via FFT in LTspice?
When using LTspice, I can see the FFT of a voltage. How can I see how much power is in a particular frequency band, and what portion of the total power it is?
The FFT in LTspice is in dB, but it's ...
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Non buffered CMOS logic gates working under load when using real components (LTSpice Sim)?
I'm experimenting with CMOS logic gates and have encountered something I am having a hard time understanding.
When I make an inverter using ideal components and measure the output, it works exactly as ...
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3 phase inverter with IR2110 LTspice
I am trying to implement a 3 phase inverter using IR2110 (model downloaded from infineon website) as gate drivers. I have tried to simulate the circuit using LTspice but I am having some issues.
This ...
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How can i check what pin is configured to what netlist order from the SPICE model?
I am trying to make a model for an op-amp (AD8000) in LT SPICE. So far here is what i did:
First I downloaded the model from https://www.analog.com/en/products/ad8000.html
and opened it from my ...
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Why does LTC6253-7 not perform properly on LTspice?
I am working with LTC6253-7 op amp which should have a bandwidth of 2 GHz but when I simulate the output for a follower and the output is being severely attenuated. Is there a technique that must be ...
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What is this pin for on LTC6253-7 [closed]
I have tried looking at the datasheet but can't seem to find any information on this pin.
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How to stimulate PSRR of LT3060-2.5 and LT1761-2.5 in LTspice?
I tried following the steps on the analog devices website but it seems that with these components the results are not close to the datasheet while when I try this method with others it works.
Do you ...
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Are there any LTspice models for OP AMPS with GHz bandwidth? [closed]
I would like to try experimenting with op amps to use as buffers for oscillators. I know op amps exist for such applications because I have found them but none of them have LTspice models. Let me know ...
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Why are my results different from their PSRR scheme?
Even though I followed every step given in the Analog devices website, the results were still different and I don't know why. Can anyone give me a solution?
Here is my result:
But their PSRR ...
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Why is my simulation in LTspice so much way off from my hand calculation for common gate CMOS?
my circuit is here.
$$
- V_X (g_{m1} + g_{mb1}) + \frac{V_F - V_X} {r_{o1}}
=
0
$$
$$
\Rightarrow
\frac{V_F} {V_X}
=
1 + (g_{m1} + g_{mb1}) r_{o1}
$$
$$
\frac{V_X} {V_T}
=
\frac{R_1} {R_1 + R_2}
$$
$$...
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Why does the opamp output not swing to vdd or vss in the simulation?
Why does the output of the opamp not rail to VDD or VSS when the positive feedback factor (2/3) is larger than the negative feedback factor (1/2)?
...
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How can I simulate driving a high capacitance MOSFET with a gate driver IC?
I'm trying to drive a MOSFET with approximately 2nF of capacitance, using a 1EDN7511B gate driver.
Following the data sheet sample circuit, I created this:
and tried to simulate it on LTSpice using ...
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Selecting an opamp for a voltage follower circuit using a LTspice simulation
Consider the following circuit:
simulate this circuit – Schematic created using CircuitLab
It is used to supply a 6VDC device (represented by R3) with a 12V car battery. More context on why ...
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Why is my spice model not working?
I am encountering a strange problem. I tried downloading a spice model for DMC2450UV NMOS/PMOS complementary transistor array but it doesn't open in LTSPICE. I get an error that says
could not open ...
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Trouble Adding PSpice Model to LTSpice
I am trying to simulate the PSpice model found here: https://www.ti.com/product/UCC25800-Q1#design-tools-simulation
From looking through various forms I was able to create a symbol from the .subckt ...
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Simulation problem in half bridge leg of an inverter
I am simulating Half Bridge Leg on an inverter. From the simulation, I could not understand why I was not getting proper dead time between high and low side fets. However, I set a delay time of 150ns ...
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LT spice, JK Flip Flop: Wrong behaviour when J K and Clock are high
Here's a picture of a JK Flip Flop I try to simulate with NAND gates:
This is the behavior I would expect; if Clk, J and K are all high, Q_n+1 should be negated Q_n:
However this is what I'm ...
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Dot parameters LTspice - Transconductance of MOSFET
Below is a very simple circuit to extract the transconductance value of the MOSFET.
As it is known, transconductance is known as Delta (Id) / Delta (Vgate).
For the gate voltage, I defined it as .step ...
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Why is my Thevenin voltage result wrong in LTspice?
I want to simulate the Thevenin voltage of the circuit below, where Z2 is the load, in LTspice. Does anyone know what is wrong here? The result is incorrect; the correct Thevenin voltage should be ...
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I got an unknown voltage error. How can I fix it? [duplicate]
I got an unknown voltage error. How can I fix it?
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Modelling a Desaturation detection circuit on LtSPICE
I am trying to model a gate driver desaturation detection mechanism with discrete elements on LTSpice. The waveforms I have obtained now provide a constant Vdesat of about 5.6V when MOSFET is turned ...
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No output in LTspice
I have implemented a simple circuit in LTspice which is as follows:
Now, when I want to view the output in the collector, it displays only one line.
Now let's check it in DC mode:
which is exactly ...
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I want to write v(x+)/v(vin) instead of v(x+). how will I do? [closed]
I want to write v(x+)/v(vin) instead of v(x+). how will I do?
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Is this LTSpice simulation of arduino's command for relay corrrect?
Here is a LTspice simulation for based on the video Design Relay module PCB using Altium designer
To me, it seems ok, but i am lacking of experiences.
What is your opinion on this LTSpice simulation ...
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Band Pass Filter Design Simulation
I'm trying to simulate a bandpass filter in ltspice.
bandpass filter should be in the 2-5 Hz frequency range
I calculated the capacitor and resistor value for this range. However, the simulation ...
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LTspice third party model gives problem with transient analsys
I have tried to import a third party model from TI, to be precise the op-amp A551. And somehow my circuite, a power amplifier, gives me the following error.
Analysis: Time step too small; time = 3....
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LTspice sofware Zener diode model 3bdc missing [closed]
I cannot find any models for LTspice for Zener diode breakdown voltage of 3 V. I need Zener diode because I am trying to get simple voltage stabilizer and my load cannot handle more than 3 V. I cannot ...
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Why does LT Spice simulation of AD711 op-amp show a non-zero output voltage when inputs not connected?
I am studying designing circuits. I got a strange problem with LT Spice.
I didn't connect any inputs into the amp but the result showed output...
I couldn't understand why it had the output voltage.
...
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