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Combating Zener Jitter

Started by Chris May 21, 2017
Winfield Hill wrote:
> Cursitor Doom wrote... >> >> Jim Thompson wrote: >> >>> AKA Flicker Noise >> >> Yup, pink noise. No jittering/jitterbugging involved. ;) > > Actually, I'd say you're wrong. The zener noise that we > see in avalanche mode (greater then 7 volts or so) is due > to step-wise "microplasma" ns-scale changes in current. > A decade or so ago we fully discussed it here on s.e.d., > complete with measurements, waveforms, detailed physics > paper references and the works. Nailed it down. As it > happens, the jitterbug analogy isn't so far off. > > This avalanche jitterbug noise source is not available > in the low-voltage field emission zener operating mode, > so using two sub-6-volt zeners in series in place of a > higher-voltage zener, or any of many other good schemes > would indeed be a good idea.
Is the low-voltage noise less than half, so it won't add up to more?
Tom Del Rosso wrote...
> >Winfield Hill wrote: >> Cursitor Doom wrote... >>> >>> Jim Thompson wrote: >>> >>>> AKA Flicker Noise >>> >>> Yup, pink noise. No jittering/jitterbugging involved. ;) >> >> Actually, I'd say you're wrong. The zener noise that we >> see in avalanche mode (greater then 7 volts or so) is due >> to step-wise "microplasma" ns-scale changes in current. >> A decade or so ago we fully discussed it here on s.e.d., >> complete with measurements, waveforms, detailed physics >> paper references and the works. Nailed it down. As it >> happens, the jitterbug analogy isn't so far off. >> >> This avalanche jitterbug noise source is not available >> in the low-voltage field emission zener operating mode, >> so using two sub-6-volt zeners in series in place of a >> higher-voltage zener, or any of many other good schemes >> would indeed be a good idea. > > Is the low-voltage noise less than half, so it > won't add up to more?
Yes, it's a tiny fraction. Try it. -- Thanks, - Win
I am guessing you mean low frequency noise caused by flicker noise or else load regulation error caused by dynamic loads and the ratio of Zener ESR to dynamic load ESR, resulting in voltage error.

Can you be any less specific?
Anthony Stewart wrote:
> I am guessing you mean low frequency noise caused by flicker noise or else load regulation error caused by dynamic loads and the ratio of Zener ESR to dynamic load ESR, resulting in voltage error. > > Can you be any less specific?
From nanoamps,to at least 3mA (max current spec), the Codatron® does not have any of the normal zener avalanche noise
On Sunday, 21 May 2017 07:10:10 UTC-4, Chris  wrote:
> Has anyone got any suggestions as to how to best deal with the phenomenon > of jittering zeners? Preferably without adding excessive complexity to a > circuit, I mean.
Can U be more explicit on this question? Part number: Bias current. Noise level Vpp - spectrum of noise, dominant, spread, slope - impedance of circuit connected to zener; Resistance, inductance, capacitance, length of wire/type balanced? unbalanced? This is what I sarcastically meant by Can U be less explicit? Thanks to R. Baer reference to Codatron shed some insight. 60 microamps is the specified Ireg. and "standard models" are rated for +/-2% Voltage noise 20µA to 500µA at constant temperature.