N
Nemo
- Jan 1, 1970
- 0
I am trying to evaluate whether to use tantalum versus OS-CON aluminium
electrolytics as the output decouplers for some linear postregulators
after a (relatively low noise) switcher. This is for a high gain
amplifier that will be operating down to audio frequencies. I've come
across references to aluminium electrolytics being noisy, but no firm
details (kind of odd as there are lots of details about ceramics'
problems under bias, wet vs dry tantalums etc). There's also some
references to "low noise" aluminium electrolytics for audio work, but I
don't know whether to take them seriously as audiophools believe all
kinds of weird stuff. So, can anyone advise if aluminium electrolytics -
specifically low ESR solid electrolyte types - have some kind of noise
problem? I know tants are NOT microphonic but I've not come across any
info about electrolytics and microphony one way or another.
Assuming they do not, I favour them over tants because their ESR is
lower, I get the impression that tants' ESR is poorer at low
frequencies, and I can get electrolytics at higher voltages (I like to
run caps at about double their rated voltage under the impression this
improves their reliability). The load on these linear regs will be
fairly constant, so ripple current will be low.
Thank you,
electrolytics as the output decouplers for some linear postregulators
after a (relatively low noise) switcher. This is for a high gain
amplifier that will be operating down to audio frequencies. I've come
across references to aluminium electrolytics being noisy, but no firm
details (kind of odd as there are lots of details about ceramics'
problems under bias, wet vs dry tantalums etc). There's also some
references to "low noise" aluminium electrolytics for audio work, but I
don't know whether to take them seriously as audiophools believe all
kinds of weird stuff. So, can anyone advise if aluminium electrolytics -
specifically low ESR solid electrolyte types - have some kind of noise
problem? I know tants are NOT microphonic but I've not come across any
info about electrolytics and microphony one way or another.
Assuming they do not, I favour them over tants because their ESR is
lower, I get the impression that tants' ESR is poorer at low
frequencies, and I can get electrolytics at higher voltages (I like to
run caps at about double their rated voltage under the impression this
improves their reliability). The load on these linear regs will be
fairly constant, so ripple current will be low.
Thank you,