Maker Pro
Maker Pro

Electrical circuit Analysis

electronicsLearner77

Jul 2, 2015
306
Joined
Jul 2, 2015
Messages
306
I am trying to understand the below circuit
1693484246400.png
My analysis of the circuit is since 5V is connected to both ends of the circuit there will be no current flow. Is it correct? Anything more i can understand from this circuit, this circuit is created by me to analyze different ways.
 

danadak

Feb 19, 2021
795
Joined
Feb 19, 2021
Messages
795
My analysis of the circuit is since 5V is connected to both ends of the circuit there will be no current flow. Is it correct?

No, the transient source, V2, is not constantly at 5V


Regards, Dana.
 

crutschow

May 7, 2021
861
Joined
May 7, 2021
Messages
861
I get 0 Amp.
Is it that i shall not do transient analysis for constant voltage supplies?
Yes, you can do transient analysis with constant voltage supplies.
Why would you expect other than 0 amps?
Can I assume this also as 0 amp current since it is in fA?
Yes, that value is approaching the precision of the Spice calculations.
I don't understand the behavior.
What don't you understand?
With zero voltage across the components (the same signal from both sources) you get essentially zero current, as would be expected.
If you want to see some significant current, then make one source a DC voltage.
 
Last edited:

electronicsLearner77

Jul 2, 2015
306
Joined
Jul 2, 2015
Messages
306
What don't you understand?
With zero voltage across the components (the same signal from both sources) you get essentially zero current, as would be expected.
If you want to see some significant current, then make one source a DC voltage.
Since the current seem to be fluctuating increasing and decreasing instead of a straight line.
If you want to see some significant current, then make one source a DC voltage.
Yes i am trying that i will show.
 

crutschow

May 7, 2021
861
Joined
May 7, 2021
Messages
861
Since the current seem to be fluctuating increasing and decreasing instead of a straight line.
But that's a very tiny current, likely to the limits of the computing precision in the simulator.
No matter how many digits the current is computed too, it may never be exactly zero.
 

Harald Kapp

Moderator
Moderator
Nov 17, 2011
13,769
Joined
Nov 17, 2011
Messages
13,769
Your calculations are good in the first part (0 ms -> 1 ms).

In the second part (1 ms -> 2 ms), however, you ignore the term (v1-v2)/r and use the result from part 1 to calculate a decaying current. What is your reasoning for doing so?

Consider instead [math] i(t) = \frac{(v_1 - v_2)}{R} \times (1 - e^{(-\frac{t}{\tau})})[/math] for [math] t \rightarrow \infty[/math]
 
Last edited:

electronicsLearner77

Jul 2, 2015
306
Joined
Jul 2, 2015
Messages
306
Your calculations are good in the first part (0 ms -> 1 ms).

In the second part (1 ms -> 2 ms), however, you ignore the term (v1-v2)/r and use the result from part 1 to calculate a decaying current. What is your reasoning for doing so?

Consider instead [math] i(t) = \frac{(v_1 - v_2)}{R} \times (1 - e^{(-\frac{t}{\tau})})[/math] for [math] t \rightarrow \infty[/math]
The circuit i have drawn and the results i am getting are completely mismatch, i think the circuit is wrong or the spice is not doing the simulations properly.
 
Top