Questions tagged [ngspice]
Anything related to NGSPICE, an open-source SPICE simulation program.
147 questions
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Why does the following simulation not work regarding a zener diode regulating a LED?
Approximate schematic (for visualizing the topology only; the part identifiers are not accurate):
simulate this circuit – Schematic created using CircuitLab
Simulation:
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Can ngspice be prevented from keeping the whole history in memory?
I would like to run a lengthy ngspice simulation. I notice the bottleneck is not CPU time (I am willing to wait quite a while for results) but memory (...
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Simulating and understanding an old circuit board from old electric vehicle (NGGSPICE)
I have been recently working on a really old electric vehicle and going through all electronics to understand how it works. I stumbled across this rather weird analogue circuit which uses comparators ...
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What is the explanation for this strange simulation result?
What is wrong with the below simulation? Why does V(cmpout) eventually go to 2.5V?
The file lm393.cir is available from: https://...
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meas directive has issues with expressions and parameters [ngspice]
In a netlist being simulated using ngspice, why do the following expressions evaluate to different results:
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CMOS analog design: Is there a difference between sizing using multiplier and width?
I'm beginning to learn about analog design in CMOS technology using the SkyWater 130 nm PDK on ngspice.
Doing some research I started to implement the \$g_m/I_D\$ approach to avoid excessive iteration ...
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No compatibility mode selected in ngspice
I have just started using ngspice and moving from LTSpice due to its higher speed when processing very large netlists, and thus would like to take advantage of the ltps compatibility mode to be able ...
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Discrepancy on Ngspice Simulation
I'm trying to simulate a boost converter on Ngspice. Purely for interest I decided to simulate the "real" circuit as well as a more idealized version of it. However, the simulated results do ...
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KiCad Simulation: Automatically changing (stepping) the input voltage during the simulation?
I am using a VDC spice simulation power source, and the power is set to dc(24) (24 volts).
I want to change this so that I have a list of voltages and timesteps ...
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Follow-up: Why doesn’t ngspice show any current variation with RD in this LED switching circuit?
This is a follow-up to my previous question.
I'm simulating a small switching stage in ngspice that should turn on an LED when the input signal goes LOW.
The circuit is this:
The logic is invertive: ...
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Static Noise Margin (SNM) computations as described in an old paper
I have recently read an old paper that describes a way to implement a simple circuit by which we can calculate the SNM for 4T and 6T SRAM. I have partially implemented the circuit to see if it works, ...
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Model PT100 in ngspice
I have the next subcircuit about PT100, SPICE gives me an error and I would like to fix it to use it.
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Trying to replicate a full-wave rectifier circuit in ngspice, but I'm running into an issue where the output isn't behaving as expected
I am in 12th grade, and I have just started learning ngspice. I was experimenting with a part of a circuit that works as a full-wave rectifier, which I found online. I was trying to apply it and ...
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How to fix my envelope detector script
I am 17 years old. I'm still in 12th grade. However, I love discovering new things and learning so I can be a more informed person.
So, it was suggested to me that I try to script an envelope detector ...
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Simulating a basic bridge-rectifier circuit
I went through this SE post before asking my question:
How do you design a bridge rectifier circuit?
I have been continuously trying to simulate bridge-rectifier circuit in KiCAD and have kept failing....
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