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.
2,630 questions
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Powering an opamp with a reference voltage from a zener diode
I'm making a PSU so I need to create a Vdd for the DC-DC switcher I am using that will power the switcher whilst the auxiliary supply is offline.
I decided to use an opamp comparator to drive a P-...
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Voltage Comparator Project
I'm working on an electronics project and I'm trying to build a voltage comparator. The idea is: if V1 = V2, the LED should turn on; otherwise, it should stay off. I also designed a current source ...
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Buck converter bode plot (Frequency Response) doesnt match measurements
I have a LTC3833 based buck converter that I need to test. Simulations of the open loop transfer show a very low phase margin of 29 deg. I corrected this by adding a capacitor C1 of 47 pF to ITH as ...
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How to model and simulate a PCB Rogowski coil (two-halves type) with equivalent circuit in SPICE?
I’m currently trying to simulate a Rogowski coil implemented on a PCB, before moving to hardware design.
The goal is to understand its electrical behavior — induced voltage, bandwidth, and the effect ...
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LTspice simulation results of current programmed mode control for buck converter not matching one shown in the book
I'm trying to simulate the Current Programmed Mode Control subcircuit for the buck converter described in section 18.5 of the Book Fundamentals of Power Electronics by Dragan Maksimović and Erickson, ...
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LC tank resonance in LTSPICE
I am simulating a lossless LC tank driven by an AC source in LTSpice. The source frequency is the same as the tank's resonant frequency. I expect to see the inductor current and capacitor voltage grow ...
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LT Spice taking too long to finish
I'm working on a Phase-Modulation Circuit, and I have added the "AD734" IC
instead of multiplying the carrier signal with the message signal using bi.
The circuit loads to 51.3% and takes a ...
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Multiple Sub-Circuit definition error in LTSPICE
I am working on an analog project for amplifying and filtering the ECG signals. I had made the whole filter structure using web circuits available and fitting them as functional blocks.
In the above ...
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LT Spice: Why does my SCR act like a Diode in 3 ph converter simulation
I am learning LT Spice. As you can see from the waveform a lot of things are going wrong here.
The green waveform indicates gate pulse of SCR U1, blue waveform indicates anode-cathode voltage across ...
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Open-loop gain measurement in LTspice
I'm trying to find the open-loop gain of the LTC6228, after looking up on several questions on stack Exchange, I learnt that I have to auto-bias the circuit.
The answers on those questions talk about ...
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Voltage Regulator Circuit
I'm trying to solve a problem:
I need to build a circuit with an input voltage of 24V and an output voltage of 5V. But the problem is, I need a performance of 5W.
That is why I am not able to solve if ...
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SPICE simulation power supply issue
I have been working on a simple function generator circuit in LTSPICE and have encountered a problem while modifying the power supply part of the circuit. I need a split rail supply for my circuit and ...
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Why the drain voltage of a power MOSFET undergoing an unclamped inductive load switching test is not 0 V at the end of a LTspice simulation?
I am designing an unclamped inductive load Switching tester for DUTs at 3.3 kV. I am experiencing a problem in LTSpice simulations where the drain voltage of the power MOSFET under test is stuck at a ...
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Oscillations in current from two current sources driving connected loads
Long story short
I see an oscillation in current in my loads, I can fix it by adding an additional diode, but would like to reproduce the issue on LTSpice to confirm my solution addresses the problem ...
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LTspice battery simulation (need >100 W sink capability) – grammatical error with Q={Ceff()*x}
I’m trying to simulate a cell in LTspice to test charging and sinking >100 W into a pack. I picked up a behavioral model (based on Chen & Rincón-Mora's work, OCV vs SOC + RC networks - github ...
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How to fix .op spice directive not working but .trans spice directive working in ltspice simulation for a buck converter?
To illustrate the design of PI and PD compensators, Fundamentals of Power Electronics by Robert Erickson and Dragan Maksimovic book considers the design of a combined
PID compensator for the DC–DC ...
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Bode plot of the transfer function of Averaged circuit model in LTspice remains in CCM mode despite load changes
I'm trying to replicate the simulation for Fig. 15.26 (SEPIC example) shown below
using the provided combined CCM-DCM averaged switch model (CCM-DCM1 subcircuit) in LTspice, as shown below, from ...
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What does LTspice's description of the AC Analysis tool mean?
The text in LTspice's description of the AC analysis tool says the following: "Compute the small signal AC behavior of the circuit linearized about its DC Operating Point".
What does that ...
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Unused Port Error in LTSpice averaged circuit model simulation and unknown extra terms in Spice netlist
I'm trying to reproduce a simulation of the SEPIC CCM averaged circuit model using LTspice from the SPICE netlist provided by the author of the book Fundamentals of Power Electronics by Robert W. ...
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How to translate a netlist to schematic for simulating averaged switch model in LTSpice
I’m trying to reproduce an averaged switch model from Fundamentals of Power Electronics (Erickson & Maksimović) in LTspice. The book defines the subcircuit as:
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Why the 5kHz low-pass filter is not working in my simulations in LTSpice?
The circuit I'm trying to simulate is shown in Figure 1 below.
SOURCE: Tools for physiology labs: an inexpensive high-performance amplifier and electrode for extracellular recording.
Land BR, ...
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Interpreting Negative Input Impedance
I would like to accurately simulate a basic CE amplifier that I have soldered and probed with a 10 MHz sine wave applied to the input.
My amplifier Zin simulations yield a negative resistive component ...
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LTSpice Diodes Inc. Schottky Diode Spice Model Question
I'm trying to simulate this simple LDO circuit but I'm having trouble adding my schottky diode BAT750 from Diodes Inc. into the simulation.
I kept getting this error
and I'm suspecting it's because ...
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I dont know how to simulate my 1nV signal amplifying Circuit Simulation and my circuit looks very simple to work
I am doing this project where I have to simulate circuit that amplifies a signal that goes from 1.6 µV at 10 Hz to 1 nV at 100 kHz from a hydrophone. I can simulate the amplification part (2000x ...
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High Voltage Controlled Current Source with Low Voltage Control
I've been looking for the topology to realise this for a few weeks now and haven't been able to get where I want to be.
Essentially I have a 0-3.3V input voltage (Vctrl) and want to output a ...
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