ESR not listed in Rubycon datasheet?

[eponymous]

Hi all,

Qucik question regarding ESR:

Why doesn't it seem to be listed at:

http://www.rubycon.co.jp/en/catalog/...minum/e_ZL.pdf ?


Am I missing something?

Thanks.

[retiredcaps]

Re: ESR not listed in Rubycon datasheet?

Impedance = ESR. Use the 20C, 100Khz column for ESR.

[eponymous]

Re: ESR not listed in Rubycon datasheet?

Impedance = ESR. Use the 20C, 100Khz column for ESR.

Hmm, but isn't impedance Z(ω) = R + j X(ω) ?

Ah do you mean that R is effecitvely the ESR and is lumped together with the reactance? So we want the impedance to be low since it is related to R?

Also, what kind of upper threshold do we have on impedance for replacing motherboard caps?

[mariushm]

Re: ESR not listed in Rubycon datasheet?

ESR is not listed in datasheets because the value varies depending on the frequencies used in the circuit.

For example, the ESR will be a value when you use it with a 72kHz switching regulator and another value when the switching regulator runs at 200kHz.

We keep it simple and easy by considering impedance in datasheets as the ESR value. In theory, it should be very close to the ESR value for a large range of operating frequencies commonly used in electronics, if the capacitors are of higher quality, not cheap general purpose capacitors.

And... it works in practice.

So like retiredcaps says, use the Impedance measured at a positive temperature, 100kHz as the ESR.

[bigbeark]

Re: ESR not listed in Rubycon datasheet?

Any idea why, when I open the document, there is no data, just blank columns?