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  1. #1
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    Inrush pulse in 0R56, 1206 resistor....gradual degradation?

    Hello,

    We have a 0R56 , 1206 resistor which suffers the attached inrush power pulse at switch-ON. (shown in 2 scope shots of the same thing, but one is a close up)
    The initial high pulse, which is 120W high, has a base of just 40ns. Would there be any chance that over say 10 years this pulse could eventually lead to the destruction of this resistor? The product is switched on once per day.

    (after the initial high pulse, there is a 140us period where the resistor power is just 0.6W, and this is obviously harmless)

    Please answer with relation to the following resistor…..
    ERJ-8BQJR56V
    https://industrial.panasonic.com/cdb...OA0000C313.pdf

    Also, please answer with this standard 0.25W 1206 resistor in mind…
    RL73H2BR56FTDF
    https://www.te.com/commerce/Document...ocLang=English

    We know we can buy resistors such as RCWE1206 series that can definitely handle this pulse, but they are significantly more expensive, and few in number, so may have supply issues.

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  2. #2
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    kripacharya's Avatar
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    Re: Inrush pulse in 0R56, 1206 resistor....gradual degradation?

    I would think that 40nS pulse of 8.2volts should definitely not be a problem, even if it is 15 amps.

    Neither is 0.66w for 140uS.

    It is after all a resistor.


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  3. #3
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    Re: Inrush pulse in 0R56, 1206 resistor....gradual degradation?

    What you name "scope shots" are simulation waveforms under probably unrealistic conditions. How about a simulation with realistic mains impedance?


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