Is this value fine for blocking capacitor?

Gordon Freeman

Joined Sep 6, 2016
18
Im designing CE amplifier and I calculated the coupling capacitor C1 using the cutoff frequency equation and it turns out I need 0,2mcF with 2221ohm input impedance and 300Hz frequency. Is this value fine? I mean,

GopherT

Joined Nov 23, 2012
8,012
Im designing CE amplifier and I calculated the coupling capacitor C1 using the cutoff frequency equation and it turns out I need 0,2mcF with 2221ohm input impedance and 300Hz frequency. Is this value fine? I mean,
How did it work on the breadboard? Only 5 parts - it should only take a few minutes.

Or, how did it work in the simulator? LTSpice, TI-TINA can simulate and show the frequency response.

The simulators are free from Linear Technologies and Texas Instruments.

Last edited:

AlbertHall

Joined Jun 4, 2014
11,218
I don't understand your value "0,2mcF"
If your lowest frequency of interest is 300Hz then you should generally calculate the capacitor value to give the -3dB at 1/0th of that frequency - 30Hz - which for 2221Ω I make 2.39uF

Gordon Freeman

Joined Sep 6, 2016
18
How did it work on the breadboard? Only 5 parts - it should only take a few minutes.

Or, how did it work in the simulator? LTSpice, TI-TINA can simulate and show the frequency response.

The simulators are free from Linear Technologies and Texas Instruments.
Hmm, didn't know about those simulators. I will try them, thanks!
I haven't yet tested the circuit, I meant in my question if I should trust the values I receive from calculating the capacitance this way, because I know this is the way (C=1/2пf*Zin), and yet as a beginner I have doubts.

Gordon Freeman

Joined Sep 6, 2016
18
I don't understand your value "0,2mcF"
If your lowest frequency of interest is 300Hz then you should generally calculate the capacitor value to give the -3dB at 1/0th of that frequency - 30Hz - which for 2221Ω I make 2.39uF
Ahh, correct!
Oh and 1/0th means 1/10 right?