Quote:
Originally posted by peranders
I think it's a bad idea to design parts which you easy can distroy.
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Depends. I would trust National on their choice of resistor rating and assume a design issue, when it burns. Very much like a fuse. If it blows, something is wrong and needs fixing, not a bigger fuse. Usually the Zobel is there to prevent oscillations from starting, not to continuously convert them into heat. A normal music signal does not have enough HF content to affect the resistor.
It usually also strikes me as odd to see the size difference between a suitable 100nF capacitor e. g. X7R and a normal 2 W resistor, when the capacitor will have to dissipate most of the Zobel's load at audio frequencies from a much smaller case.
Quote:
Originally posted by jackinnj
you can get the 2W Vishay PRO2 series which are about the size of a 1/2 W carbon comp resistor.
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Higher power rating in a smaller package means
- steeper derating above the reference temperature and/or higher maximum temperature.
- higher temperature for a given dissipation -> higher value drift. Not an issue for a Zobel, yet must be kept in mind for certain applications.
- no space saved, because neighboring components need to be kept further away to keep them cool. Sometimes even the leads need to be left longer, because they have to help with dissipation.
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If you've always done it like that, then it's probably wrong. (Henry Ford)
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