Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [maximum-ratings]

Questions related to the maximum ratings of a component such as maximum voltage, heat and other specs which if exceeded will likely destroy the device

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Are LEDs better than we think?

Conventional wisdom about LEDs says their maximum reverse voltage \$V_{R(max)}\$ is quite limited, usually in the 5V-8V range. So, for experimentation purposes, I wanted to bring an LED into controlled breakdown, using my current-limited power…
LorenzoDonati4Ukraine-OnStrike
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How do I calculate the power rating for zero-ohm resistors?

Based on my earlier question, since there supposed to be zero voltage (V=IR) drop across a 0 Ω resistor, how do we select the power rating of such a component? For example, let's say I were to connect a zero-ohm resistor in between 5 V power source…
Dennis
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When is it okay to exceed the absolute maximum rating on a part?

I've always thought that the absolute maximum ratings on a part are the limits that thou shalt not violate. Period. End of story. However, another engineer is making the case that it's okay to exceed the absolute max rating for the input voltage…
CHendrix
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Why has my tweeter speaker burned up?

I bought a powerful tweeter (or so I thought) to experiment with the ultrasound. The device is quite heavy, and it is rated at "350 watts RMS/700 watts peak": 2'' Titanium Super Tweeter PDBT78 Its nominal impedance is "4-8 ohms" with a frequency…
SlowBot
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125 mW resistor subjected to 600 mW dissipation in professional safety system

The schematic below is the input circuit of a signalling PCB, which we buy from one of our suppliers of fire detection systems. Said PCB has to be built into a so called geographic evacuation panel which allows firemen to see in which zone of a…
Bart
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What is an AC voltage rating for a capacitor?

I thought the only thing that mattered was absolute voltage across a capacitor puncturing the dielectric, but there are some that have an AC rating, too. What does this mean? Why does the value change at different frequencies? I see Vrms vs…
endolith
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How are speakers matched with audio amplifiers? (avoiding overloading either)

I know a similar question title has been asked, but I believe that does not answer my question (and I couldn't think of a better way to phrase the question). I'm a bit confused by how exactly an amp can overload a speaker, and vice versa. Many…
midnightBlue
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Is it a problem to use a capacitor at or near its rated DC voltage?

Are there important points to consider in typical or special applications when capacitors operate with applied voltage close to their rated DC voltage? Such as: 15 V on a 16 V-rated capacitor, 24 V on a 25 V-rated capacitor, 33 V on a 35 V-rated…
Nonok cantik
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Is it safe to exceed an LED max current when ON time is less than 100%?

For an LED that is rated at 20mA, is it safe to PWM it at 40mA half the time? Will that make it nearly as bright as if continuously supplied with 20mA? Addendum: Thanks Olin and tcrosley for your answers. I didn't want to distract from the question…
lyassa
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Input voltage range of opamps

I understand that, for an ideal opamp, Vo is bounded by Vee and Vcc (i.e.; Vee < Vo < Vcc). But, what about the input voltage range? What is the allowed input voltage range in which opamp works normally? Can we apply Vn and Vi voltages which are…
hkBattousai
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Where Does VDD+0.3V Input Limit Come From on IC chips?

There are a variety of integrated circuits that specify that their input voltage can span a fairly wide (absolute maximum) range, e.g. -0.3V to 6.0V (ref, pdf page 4), and then have a "Input Voltage at any pin" constrain that depends on the input…
vicatcu
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Why would a LED datasheet specify a minimum operating current?

I am looking at the datasheet for the OSRAM Golden DRAGON® Plus LUW W5AM, a high power white LED. It has a forward current of 20-1000 mA, surge current up to 2500 mA, and I think they want you to run it at 350 mA; that is what they use for most of…
pipe
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SMD resistor maximum voltage: is 200V really a limiting factor?

I need a resistor to work with 230 VAC voltage. So 400V rating would be appreciated. However most of the chip resistor with size 1206 and above has only 200 Volts of maximum working voltage. Main of my concern is: why this voltage doesn't rise up…
Roman Matveev
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Determining how much load capacitance a 40-series logic IC can safely drive

In designing a circuit, meant to delay only the rising edge of a square wave, I've got some doubts on determining the maximum value for C1 that can safely be driven by the CD40106 CMOS logic IC. The discharging part of the cycle is no problem as…
Unimportant
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Max operating temp of IC's

Why do so many IC's have a max temp range of 125C? Is it due to packaging material tolerances, ie the black plastic enclosures and/or the bonding epoxy that holds the die to the package and/or something else?
user64750
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