Ring Oscillator

194

02:48:17

Nice oscillator.
Some small resistors have been added to account for the ESR of realistic (non-ideal) capacitors.

More information on ESR:
https://en.m.wikipedia.org/wiki/Equivalent_series_resistance

Improvement suggestions?
Give me a shout.

published 8 years ago

eekee

8 years ago

Shake your tablet. :) It seems to take a much less violent shake than most circuits. Alternatively, add a switch to temporarily charge one of the capacitors. That's my preference.

eekee

8 years ago

Now I'm at my desktop with the Chrome version of EveryCircuit, I can't find a way to insert noise at all. I'm going to start telling people to always add a switch to start it. :)

tjt263

8 years ago

It's should work on its own, without injecting noise. It's supposed to take about 10 seconds to get started.

selman

8 years ago

Stolen from Examples tab.

BillyT

8 years ago

eenee, is that just the chrome browser?

tjt263

8 years ago

What's that?

tjt263

8 years ago

@eekee These virtual components must be too perfect. In reality, I guess there would be some minor variations between capacitors marked with the same value. I tried adding a small 1Ω resistor in series with C3, just to throw it off balance a little bit; it fired up without intervention. Altering the value of any transistor or capacitor in the circuit by a fraction will also work.

eekee

8 years ago

@tjt263 Yes, the components are definitely too perfect. I sometimes make use of that intentionally, a chance to play with what would otherwise be very expensive matched sets. I feel it makes up for some other flaws, such as simple op-amp circuits suffering convergence errors if their reference voltage isn't ground. @BillyT Yes it's the Chrome app. The funny thing is it started up almost instantly today, but when I was commenting yesterday it didn't start in well over 10 seconds.

tjt263

8 years ago

@eekee There, I added a small resistor to each gate. It's working much better now.

BillyT

8 years ago

tjt263 I don't know if you realize, but to make a symmetrical circuit, you would have to join the Orange to the Red trace instead of where you have joined it, but if you do that the circuit has trouble starting. So as you stated, an unbalanced circuit appears to work best.

tjt263

8 years ago

@BillyT That sounds about right. I would have drawn it differently too, to avoid confusion, but the software is a bit stubborn.

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