Author Topic: 7805 from different brands ?  (Read 6644 times)

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Offline Monkeh

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Re: 7805 from different brands ?
« Reply #25 on: December 15, 2016, 04:20:05 pm »
Thing still getting very hot, i have no clue, measured everything, i looked for hours.

What is your input voltage and current?

The voltage is 12, the milliampere usage is 83 for the whole thing, including a 4 x opamp package on 12 volt.

Then you should expect approximately 30C temperature rise with no heatsink - this can feel rather warm.
 

Offline JanJansen

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Re: 7805 from different brands ?
« Reply #26 on: December 16, 2016, 04:31:44 pm »
Then you should expect approximately 30C temperature rise with no heatsink - this can feel rather warm.

Its getting way hotter, i now discovered the good project also gets hot even with heatsink. ( i gotto have a new DMM to measure temprature )
Now finally i made a 16 bit digital synthesizer, and get this problem, bleh.

Maybe it has peaks that my PSU dont measures because of the 2200uF elko.
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Offline JanJansen

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Re: 7805 from different brands ?
« Reply #27 on: December 17, 2016, 11:46:40 am »
Maybe the 330 ohm resistor from the optocoupler gives the peaks ?, that is almost short circuit.
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