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Two capacitors in parallel - High or Low ESR?

Ping

Feb 3, 2016
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Hi,
I want to put two capacitors in parallel in a DC circuit. I need the charging and discharging times to be as brief as possible. Should I get capacitors with high ESR or low ESR?

Thanks.
 

Gryd3

Jun 25, 2014
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Hi,
I want to put two capacitors in parallel in a DC circuit. I need the charging and discharging times to be as brief as possible. Should I get capacitors with high ESR or low ESR?

Thanks.
How do you know of ESR? You should be able to answer this yourself :)
 

Ping

Feb 3, 2016
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I'm teaching myself. Patchy background in physics.
I'm thinking high ESR, but I want to be sure before spending money.
Someone teach me!
 
Last edited:

Colin Mitchell

Aug 31, 2014
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You actually want capacitors with high ripple current capability. This really means looking at the size and selecting the biggest capacitor for the capacity and voltage-rating that you choose. Ripple means how hot they will get when in use.
 

Harald Kapp

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Nov 17, 2011
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I need the charging and discharging times to be as brief as possible.
ESR = Equivalent Series Resistance. The ESR plus the capacitance form a low pass filter with time constant t=R*C.
See for yourself how the resistance (ESR) influences charging time.
Probably the factor limiting the charge current and thus charge time is not the ESR but the max. currrent you can draw from the charging circuit.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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For rapid charge and discharge ESL actually becomes important. Capacitors designed for use in xenon flash applications are an example of a capacitor designed to be discharged rapidly.
 
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