This tag covers finding models for electrical and electronic components and circuits
2
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1answer
20 views
What is the syntax for modelling a non-linear element in Spice?
Suppose I have the following circuit. My question is how do I write the net-list in LTSpice such that f(i) = i^2 + 2 (for example) ? I couldn't find the syntax on the internet.
0
votes
0answers
10 views
State space averaged model or switch averaged model?
While modelling the buck converter, which model best describes both CCM and DCM of operation?
I'm trying to model in MATLAB for a CCM and DCM combined buck model. Can anyone help me with the best way ...
0
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0answers
44 views
Why is the dependent current source ignored?
I need to find i1 / v1 when i2 = 0.
According to the solution manual, the KVL is -V1 = 2kOhms*i1 + 1kOhms(i1 + i2), and since i2 = 0 they get -V1 = 3000i2.
Are they forgetting the dependent ...
0
votes
0answers
27 views
Spice modeling of a comparator using zero-pole transfer function
I'm designing an open-loop comparator for an analog IC. I've followed the design procedure included in the "CMOS analog circuit design" by Holberg and Allen. I've established the required gain and ...
1
vote
1answer
40 views
Modeling a real transformer: why is the excitation branch in parallel?
In the above diagram, the parallel branch containing Rc and jXm represents the excitation branch.
My question: I just can't seem to understand why the core loss current and the magnetization ...
0
votes
0answers
25 views
Does anyone have spice model parameters for 0.5W 32ohm or similar speakers?
I know that
Re = Measured Voice Coil Resistance
Le = Measured Voice Coil Inductance
Fs = Resonant Frequency
are the main parameters to make a reliable speaker model for .ac . So for a generic ...
0
votes
1answer
52 views
Approval before I modify the form factor of an ATX PSU
I want to use an ATX PSU with my home build 3d printer but there is not enough space to fit it because of the height. Initially while designing the printer I planned to use an LED strip PSU. Now I ...
0
votes
1answer
56 views
Transient analysis of a step down converter with control loop
I am trying to run a transient simulation of a step down dc-dc converter using ideal components. This includes a feedback loop consisting of an error amplifier. I am interested in transient response ...
1
vote
2answers
29 views
Transistor level netlist benchmarks
I'm PhD student in CAD/EDA field. My research topic covers VLSI standard cell's layout design and detailed routing. To make my research results more reliable, I would like to test proposed algorithm ...
0
votes
1answer
68 views
Modeling a Time to Digital Converter in Verilog-AMS
I'm trying to write a TDC model in Verilog AMS. I'm really new at the AMS part of Verilog.
The problem I'm running into is in assigning the final state of the TDC to the outputs. Below I present the ...
1
vote
1answer
49 views
AC-model of Integrated Boost-Flyback converter
I am designing a small SMPS to light a few Nixie tubes from an ordinary USB charger. This requires a high voltage gain around 40 which disqualifies many of the typically used topologies. I have grown ...
1
vote
1answer
78 views
Modelling Circuit from FSM using Verilog
I am trying to understand the concept of modeling a circuit from a FSM in Verilog.
I have tried to write down the procedure that I have used in the image below just to make sure that I did it right:
...
1
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0answers
92 views
Importing a verilog-a compact model in ltspice
I have a Verilog-A compact model, and would like to import it in LTSpice. I tried to google this, but to no avail unfortunately. Can anyone tell me how to do this if possible?
By the way, in spectre ...
0
votes
3answers
66 views
Where do I find models for various common op amps for use in LTSpice
I have just started using LTSpice. I need to simulate a circuit with op amps, where the parasitic elements of the op amp may effect performance. So I need to try different 'real' op amps to see which ...
0
votes
1answer
34 views
How can one model a microcontroller's power consumption?
I was checking out this EE.SE question and thought I might play around with a similar idea on my own. I started to think about how I would model a power supply for a microcontroller with two possible ...
1
vote
1answer
67 views
How do you get from experimental measurements to models?
Many analytical models in the literature are "based on empirical measurements".
For example, for a radio propagation model, one would go out in the field, take his equipment and perform a lot of ...
1
vote
1answer
33 views
Ideal SPICE Model of Op-Amp with Power
I know that the ideal operation amplifier model is a single voltage controlled voltage source. My question is how to extend this ideal model, in a minimal way, to account for power supply rails (V- ...
0
votes
3answers
72 views
r0 vs ro in transistors ac modeling?
I'm a beginner in electronics field . In hybrid and pi and T models we have a resistance called r0 or ro . What's the correct name ? Is it "r-zero" or "r-o (15th alphabet letter)". Pls give ...
1
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0answers
30 views
What is the polarisation constant /resistance in the context of (Lithium Ion) Batteries?
I'm trying to implement a Model of a Lithium Ion Battery in Dymola/Modelica based on the following paper but -of course- in the data sheet of the producer i couldn't find a couple of needed parameters ...
2
votes
1answer
63 views
Measuring BJT (Ebers-Moll) parameters
I am currently attempting to measure the parameters of a "vintage" germanium BJT in the hope of creating an Ebers-Moll model from the data. So far I have been unable to find a comprehensive source on ...
0
votes
1answer
118 views
Transformer model in Power Systems VS Coupled Inductors model
I know 2 models for a transformer one is to treat it as Coupled Inductors and the model will be:
In this model if there are no flux leakage the coupling factor is k=1 and therefore ...
0
votes
1answer
23 views
Transfer fuction model
An electrical circuit comprises a resistance R=1.1ohms in series with an inductance L=1.4H (model Ldi/dt+iR=v). Given that the transfer function model linking voltage supply to current is given as ...
2
votes
2answers
395 views
Modeling the elevator as a finite state machine
This is my first post here. Nice to meet you all!
I've read a related question here and am still having issues.
The task:
There is a building consisting of 7 storeys (indexed 0-6). Design a system ...
2
votes
2answers
285 views
Finding transfer function of DC motor
I am trying to find the transfer function of a DC motor experimentally using the step response method, for that I am using the following circuit:
Hooking up to Fin a transmissive photosensor that ...
1
vote
0answers
237 views
SPICE model for DRAM transistor
My research group wants to investigate how powder delivery network (PDN) noise (such as ground bounce) can affect the retention time of DRAM cells. The idea is that the power noise increases the ...
1
vote
1answer
192 views
Brushless DC motor model for model-based design
I have seen this diagram or something like it being used to model a DC brushed motor:
With a resistance, inductance, input voltage and load inertia basically specifying the motor.
What would be ...
1
vote
2answers
123 views
AC Motor torque simulation
I am trying to do a simulation on the start up speed to a system powered by an AC motor.
As part of this I am trying to find a mathematical torque/speed curve that I can use.
I expect a curve that ...
0
votes
0answers
67 views
Problem of Convergence in simulating a model using Cadence Orcad 16.6 Pspice software?
I have a simple problem in simulating my circuit. First I will post all the details, Schismatic and netlist, then I will talk about the error and its options.
I am using Cadence Orcad 16.6 Pspice and ...
1
vote
4answers
333 views
Use of controlled sources (VCCS, VCVS)
Voltage-controlled current sources (VCCS) can be used when we need to model a device or any part having voltage as input and current as output. Same is the case for voltage-controlled voltage sources ...
1
vote
1answer
174 views
I want to make a cd4049 cmos inverter spice model
I know the cd4049 is just two FET's but I don't know how I can model those transistors to be at least near what one would expect from the behavior of the IC.
Also, what parameters are absolutely ...
0
votes
2answers
822 views
Positive feedback and virtual short in Operational Amplifiers
Can anyone please explain, with sufficient mathematics, why the virtual short concept is not applicable to an operational amplifier in positive feedback.
1
vote
1answer
109 views
Solar cell electrical model from datasheet
I would like to build an electrical model for a solar cell based on its datasheet specifications. As an example, I retrieved one from Digi-Key:
...
4
votes
2answers
163 views
Modeling long wires in circuits
What's the proper way to model really long wires in circuits (18ga, ~1500 ft)? I'm aware that over long lengths start to accrue non-ignorable resistances. I'm wondering if they start to get other ...
-2
votes
1answer
208 views
Gain of a differential amplifier in PSpice
I am modelling a differential amplifier in PSPice using MOSFET. Here is the schematic:
In this i want to track the gain of the circuit by changing the value of the width of NMOS. Now can anybody ...
0
votes
0answers
78 views
Pspice: Trouble in modelling an inverter using Current Mode Logic in Pspice
I am using or-cad 16.6 for modelling an inverter using CML logic family. I need a swing of 400mv with this inverter. I want to build this by using MOSFETS. Following is the schematic of the inverter:
...
0
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0answers
69 views
Modelling a BJT with easy equations, but having false scenarios
NPN:
simulate this circuit – Schematic created using CircuitLab
...
1
vote
1answer
36 views
Value of Drain Current in BSIM3v3 in triode region
Here the value of drain current has been given as per the BSIM3v3 MOSFET model, but is there any reference where it has been shown how this value was calculated and what is the meaning of the ...
0
votes
1answer
219 views
Input Characteristics of MOSFET in triode region?
When a MOSFET is operating in saturation region, i.e. \$V_{GS} > V_{th}\$ and \$V_{DS} ≥ ( V_{GS} – V_{th} )\$, the drain current equation clearly indicates the parabolic relation between the drain ...
0
votes
2answers
171 views
How to model a repeating sinc pulse in LTSPICE?
I'm looking to model a repeating sinc pulse in LTSPICE, however I can only get it to fire once. I'm looking to delay it by x many ms, and trigger the pulse the again.
Is this possible with LTSPICE ?
1
vote
1answer
71 views
Issues with RF transmitter project
I've constructed a RF transmitter circuit and have been getting numerous problems. after modelling the circuit on a breadboard and testing it we got unexpected readings. these include
411.5hz ...
0
votes
1answer
79 views
Control Engineering: Model parameter estimation for a motor which will be under various loads
I am creating a closed loop controller for a motor which is part of a robotic arm. I give it a required angle, the controller calculates a control input, the motor moves, a pot feedbacks the angle, ...
1
vote
1answer
224 views
Passing user parameters into a custom PSpice model
I am building my own simulation parts in Orcad 16.6:
I can build a schematic and take the generated netlist to use as a stand-alone component, but I want to be able to change parameters inside the ...
2
votes
1answer
592 views
State space modeling with disturbances using Matlab
I am doing a project which involves modeling a quadcopter in state space form using matlab. I first had to linearize the quadcopter equations of motion, and now have to implement them in a matlab ...
1
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0answers
126 views
Problem with crystal oscillator based RF circuit
As a little experiment, a friend and I are trying to get a crystal oscillator based transmitter and receiver to work. So far we're having no luck.
Here are the wiring diagrams:
We once got the ...
1
vote
1answer
298 views
Mathematical model of the temperature of resistors/heatsinks?
I want to model the transfer function of a resistor mathematically, and am after some resources / tips on if it's possible to do so.
For example, if I put 1V into a 1 Ohm resistor, I want to know how ...
1
vote
4answers
246 views
Why can't I get a output lower than 0V in this diode and capacitor circuit?
In the image above green is my input (node left side capacitor) and blue is my output (node right side of the capacitor).
I would expect that the blue signal would follow the input, but it does not ...
7
votes
6answers
659 views
Does anyone use op-amps for modelling physical systems any more?
I am studying for my System Modelling and Simulation exam. So the textbook says there are three categories of models.
Graphical - block diagrams and signal flow graphs.
Physical - physical similarity ...
2
votes
1answer
260 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:
...
1
vote
2answers
616 views
How would I solve this Block Model diagram of a DC motor?
Sorry if this website isn't the place for this question but I am really lost on how to solve this and I'm being tested over it tomorrow.
I somehow keep on getting the answer 475 instead of the ...
1
vote
1answer
85 views
Modeling languages for Hardware platforms (embedded systems) [closed]
I'm looking for some modeling languages in order to design hardware platforms in the context of embedded systems.
I already had a look at the following:
AUTOSAR
UMLMarte
SysML
I wonder if there ...
