How Does a Capacitor Introduce Phase Delay in a Circuit?

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TL;DR
Understanding the phase delay
I simulated the below circuit to capture the phase delay between input voltage and output current in LTSpice
1689755433868.png

How do i measure the phase delay introduced due to capacitor?
1689755562602.png
 

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When you are using the term "delay" - which signals do you have in mind? Such a delay is the delay between two signals (voltage and/or current) resp. the corresponding phases of these signals,
When you remember your own definitions, you will know what you have to measure/simulate.
 
This would normally be done with sine waves, not square waves. This is because the phase delay depends on the signal frequency. A pulse waveform contains many frequencies. It still can have a phase shift, but it's complicated. So sine waves, which are a single frequency, often swept through a range to make a frequency response (Bode) plot, is what most EEs use.

In any case, you need to specify the conditions, like the input waveform, for phase delay to make sense.
 
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PhysicsTest said:
TL;DR Summary: Understanding the phase delay

I simulated the below circuit to capture the phase delay between input voltage and output current in LTSpice
It looks like you are using a Transient Analysis -- that is not the type of analysis that you should use to see the Frequency Domain characteristics of a circuit. Have a look at this article, and let us know what a better SPICE analysis mode would be... :smile:

https://techweb.rohm.com/know-how/simulation/7916/
 
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I am analyzing the circuit and will come up with the exact problem i am facing.
 
PhysicsTest said:
I am analyzing the circuit and will come up with the exact problem i am facing.

A square wave will charge a capacitor up as soon as it is applied because it is similar to direct current.

Are you wanting to test the time constant, tau, as it is charging?
 
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osilmag said:
A square wave will charge a capacitor up as soon as it is applied
More accurately, a square wave will start to charge up a capacitor with the initial application of the first pulse. Subsequent pulses alternately start to discharge it and recharge it... (see the OP's transient SPICE simulation):

1690549470447.png
 
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