what is "safe area protection"

[ady]

Hi,

I have just a simple question. What is "safe area protection"?

Thank you in advance for your answer,
ady

 

[justDIY]

google for athletic cup perhaps?

 

[Hank Fletcher]

safe area protection

The protected area inside a safe, when it's locked. Technically, it should be called "safe volume protection."

 

[justDIY]

The protected area inside a safe, when it's locked. Technically, it should be called "safe volume protection."

Perhaps the area around, above and below a safe could be called the safe area.

Making the safe less accessible improves its protection. Most free standing safes are not cracked on site, but rather hauled away by tow truck or other means, and broken into after the fact. The safe area should be protected by means of poured reinforced concrete walls, ceiling and floor. Access controls to the room containing the safe is also something to consider. Multi layer and multi factor security is a good idea for protecting the area around any safe, large or small.

 

[audioguru]

Do you want to know about a power transistor's Safe Operating Area?

 

[ady]

Hi everybody,

So, I am not master of electronic circuits, but nevertheless my question was about electronic circuits. I am sorry if the question was too vague.
In the datasheet of a voltage regulator (7815), I have found "Safe area protection for
the output transistor is provided to limit internal power dissipation."
So it is indeed related to a transistor.

ady

 

[ericgibbs]

Hi everybody,

So, I am not master of electronic circuits, but nevertheless my question was about electronic circuits. I am sorry if the question was too vague.
In the datasheet of a voltage regulator (7815), I have found "Safe area protection for
the output transistor is provided to limit internal power dissipation."
So it is indeed related to a transistor.

ady

hi,
It simply means that within the 7815 internal circuitry are sensors which limit the maximum power dissipation of the 7815 so it dosnt self destruct.

If too much current is drawn and/or the current/voltage drop across the 7815 is over a certain limit and it over heats, it will go into 'thermal shutdown' to prevent damage to itself. It will recover as it cools.

Is this OK?

 

[ady]

Hi Eric,

Thanks a lot for your answer, this is fine.

Adrian

 

[audioguru]

Some regulator manufacturers call it Safe-area Compensation.

It is more than just thermal shutdown.
The max output current is reduced as it heats. It is typically 2.2A and it reduces to 1.0A when it gets hot and has less than 10V across it.
The max current also reduces as the voltage across it increases even if it does not heat. With a 23V input and its output shorted, the Texas Instruments uA7815 has a typical max output current of only 230mA when its junction is at room temperature. The max current is lower if the voltage across it is higher and if its temperature is higher.