# Electric current being alternated with continuous part

DaTario
TL;DR Summary
In which scenario a current may exhibit alternated and continous character together?
Summary: In which scenario a current may exhibit alternated and continuous character together?

Hi All,

I would like to know in which scenario an electric current may exhibit alternated and continuous character?
Something like $$I(t) = I_0 \sin (\omega t) + I_1$$.

## Answers and Replies

darth boozer
A simple example is ripple on the DC output from a poorly smoothed power supply. The output is DC with AC superimposed on it. Another is the DC supply to the LNB on a satellite TV dish, which is passed on the same coaxial cable bringing the signal (which is AC) to the receiver.

Asymptotic and Dale
Gold Member
2022 Award
A simple example is ripple on the DC output from a poorly smoothed power supply. The output is DC with AC superimposed on it. Another is the DC supply to the LNB on a satellite TV dish, which is passed on the same coaxial cable bringing the signal (which is AC) to the receiver.

Mentor
I would like to know in which scenario an electric current may exhibit alternated and continuous character?
Another example of a DC current with an AC component (although not sinusoidal) is the i(t) current through the inductor of a "Buck" topology DC-DC converter. The average of the triangular current waveform is the average output current of the DC-DC converter (at the output voltage which is being regulated by the converter), and the ripple current depends on the switching frequency and the value of the inductance...

https://www.maximintegrated.com/en/app-notes/index.mvp/id/2031
https://www.electronics-notes.com/a...-step-down-buck-regulator-dc-dc-converter.php