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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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 ...
- 69
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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)?
...
- 292
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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 ...
- 1,225
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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 ...
- 377
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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 ...
- 11
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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 ...
- 405
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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 ...
- 698
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2
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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?