Timeline for Unexpected dominant pole in active-RC circuit
Current License: CC BY-SA 3.0
5 events
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| Feb 11, 2015 at 22:14 | comment | added | Kuba hasn't forgotten Monica | @BowPark Do you really expect us to have to look somewhere for the values you used for your filter and for the actual circuit that you've used? As it is, we can't even simulate it in CircuitLab. It's really on you to try to simulate it in multiple simulators and compare the behavior. You should only ask such a question when you verify that multiple simulators all agree on the behavior. | |
| Feb 11, 2015 at 12:21 | comment | added | BowPark | Please, read the end of the question: I have updated it with some more informations. The values are correct, in fact the RLC prototypes have a high-pass behaviour, without any 10 GHz pole, both in the 3rd order and in the 8th order case. The 8th order circuit is built with the same procedure; it has simply the L1, L2, L3, C2 cell repeated 3 times and then a capacitor C8 before the load. | |
| Feb 9, 2015 at 16:05 | comment | added | Kuba hasn't forgotten Monica | @BowPark What I meant was that in a real circuit, the parasitics would determine the response, not whatever the simulator told you, or whatever you put into the circuit. At those frequencies, the shape of the traces is very, very important :) You need to try tell us exactly what 8 pole circuit did you simulate (I see none), and exactly in what software. I'd try it first in something other than CircuitLab first. For all I know, the values you use in your 8 pole circuit are bad. Where did you get the values? | |
| Feb 9, 2015 at 10:58 | comment | added | BowPark | I don't think it is determined by parasitic capacitances, which should not even be present in that fully-ideal active-RC circuit. I updated my question: raising the order of the circuit, the pole decreases its frequency and it is at about 100 Hz for an 8-order high-pass filter realized with the same procedure. Do you notice anything in the topology that could originate the pole? | |
| Feb 6, 2015 at 14:28 | history | answered | Kuba hasn't forgotten Monica | CC BY-SA 3.0 |