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Suppose I have a 200 V 200 µF capacitor and a 16 V 200 µF capacitor, and suppose I have a circuit that requires a 16 V 200 µF capacitor.

Can the 200 V capacitor be used instead of the 16 V one and will they work the same? Apart from the obvious overkill are there any disadvantages (speed, power dissipation... certain limitations)?

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  • \$\begingroup\$ the capacitors should work the same as long as they are the same type. ... the 200V is the guaranteed dielectric breakdown voltage (if you go a certain percentage above that voltage, you stand a chance of destroying the cap) \$\endgroup\$
    – jsotola
    Jan 23, 2018 at 2:18
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    \$\begingroup\$ Size... Higher voltage, larger insulation, larger size... \$\endgroup\$ Jan 23, 2018 at 2:35
  • \$\begingroup\$ Yes it should work the same. \$\endgroup\$
    – skillz21
    Jan 23, 2018 at 2:54
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    \$\begingroup\$ The answers so far ignore the way dielectric is formed in an electrolytic capacitor. Aluminium (wet) electrolytics may become leaky if they aren't biased to a significant fraction (like half) their rated voltage to keep the dielectric formed. I'd happily substitute a 25V cap for a 16V one, but not a 200V one, if reliability mattered. \$\endgroup\$ Jan 23, 2018 at 10:40
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    \$\begingroup\$ Capacitors have more parameters, not just a capacitance and voltage rating. The others could be ESR, frequency response, maximum ripple current and so on. \$\endgroup\$ Jan 23, 2018 at 11:40

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They both would work if they are within the voltage range. However, they do not work the same. Of course, besides dimension differences, there are different parameters that change when having different voltages and also depending on the capacitor type.

For ceramic capacitors you have to consider the bias voltage (VDC). That is, when increasing the voltage the capacitance decreases. You can see the difference between two 100 µF capacitors, one rated at 25 V and the other to 6.3 V. Both would support 5 V, but the capacitance of the 6.3 V capacitor would be lowered (around 50%). The bias voltage is actually dependent on size rather than the capacitor voltage level, but it is true that higher voltage levels usually means higher volume.

Enter image description here

Aluminium electrolytic capacitors are not as vulnerable to the bias voltage problem as ceramic ones. But capacitors with a lower voltage rating usually have higher ESR. That is something that might be considered (especially if there are no ceramic capacitors that have a very low ESR around). Also, tolerance values are usually worse for a higher voltage level.

So in general they would work the same for most applications. But there are some issues to consider when choosing the voltage level. The safest choice would most likely be to have just the voltage level needed for your application with some margin. But going with higher voltage levels, like in your case, is not usually a problem. It is more critical when going for lower voltage levels. Here you have a small recap of different capacitor types.

Enter image description here

Sources:

Graph: Murata Electronics.

Table: NIC Components.

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    \$\begingroup\$ On ceramics, note that DC bias effects not an issue for class 1 (C0G) dielectrics; I am aware that those are limited to a few nF, but you may wish to clarify :) \$\endgroup\$ Jan 23, 2018 at 9:34
  • \$\begingroup\$ +1 for the graph and table. Where did you get them from? \$\endgroup\$ Jan 23, 2018 at 13:40
  • \$\begingroup\$ The graph is taken from a simulator offered by Murata Electronics. It is a quite good tool in my opinion. The table is taken from Nic Components \$\endgroup\$
    – user175624
    Jan 23, 2018 at 13:55
  • \$\begingroup\$ @user175624 - Nice answer. FYI you must correctly reference material from others in your answers, to prevent downvotes or removal of answers etc. \$\endgroup\$
    – SamGibson
    Jan 23, 2018 at 23:39
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As long as the working voltages are within range nothing will explode.

But be aware that for certain capacitor types (especially high voltage aluminum electrolytic), the tolerance tends to be worse at high values of voltage and capacitance.

HV caps can also exhibit more "memory effect" than their low voltage counterparts.

For the values you stated, all of the above effects will be minimal. But as others have noted, the most noticeable disadvantage is size.

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You will find almost every Alum Electrolytic cap improves on Dissipation Factor with rising breakdown voltage rating. This means lower D.F. = lower tan δ = lower ESR ( all equivalent yet different units related to max ripple current rating)

However you can also find a wide range in e-caps spanning a 100:1 range in ESR*C=T products. This means one could find a 16V cap that can handle more ripple current than the worst 200V cap at the same C rating.

Will it work the same? Almost. But that depends on what "same" means.

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  • \$\begingroup\$ "Same" means that other than the price differences and size, they would be interchangeable in the circuit, without affecting the circuit's functionality\operation. \$\endgroup\$ Jan 23, 2018 at 3:07
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    \$\begingroup\$ To definitively answer that one would have to known 1: the needs of the circuit and 2: a lot more specifics about the two capacitors. \$\endgroup\$ Jan 23, 2018 at 3:28
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200 V 200uF capacitor means, it can tolerate upto 200 V which is its dielectric breakdown voltage. So it can be used for the mentioned application.

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  • \$\begingroup\$ What's your verdict? Will they work the same? \$\endgroup\$ Jan 23, 2018 at 4:37
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    \$\begingroup\$ This answer misses the main point of the question. I believe the OP was able to compare 16 to 200 himself. \$\endgroup\$ Jan 23, 2018 at 9:55
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Different capacitor types have different DISTORTION properties. The effect seems to be the mechanical-squeezing of the dielectric material. Walt Jung examined this, as did Society of Audio Engineers.

I recall distortion numbers of -70dBc.

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  • \$\begingroup\$ OP doesn't mention different types \$\endgroup\$
    – pipe
    Jan 24, 2018 at 8:00

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