Temperature Measurement

[satheeshvelu]

Hi all,

I'm doing temperature measurement of an IC.

This IC is having a operating temperature range (-40degC to +85degC).

But for some parameters (like Operating Current), I have to measure for a temperature range of (-50degC to +150degC).

May I know why do I need to measure at the out of spec. temperatures ?

Is there any reason behind it ?

Thanks,
Satheesh

 

[erikl]

Application in special deployment regions (military, automotive), where only a few parameters must be tested?

 

[cesczhang]

I think the temperature inside the IC is higher than its application environment temperature is another reason

 

[erikl]

I think the temperature inside the IC is higher than its application environment temperature is another reason

True; but in this case all parameters should be tested at least at the extreme high temperature, not only a few of them. Moreover, what would be the motivation for the lower extreme temperature test?

 

[satheeshvelu]

This IC is not used for military purpose.

I still do not understand why the measurement temperature changes between the parameters.

 

[keith1200rs]

Simply ask the person who has given you the requirement/instructions.

Keith.

 

[satheeshvelu]

Hi Keith

Actually this question was asked by the person who gave me the instruction.

Unfortunately, I don't want to say "I don't know" and hence I'm digging out the answer.

Hopefully I will get to know the answer from him tomorrow and share with you.

Thanks a lot.

Satheesh

 

[keith1200rs]

Satheesh,

I understand.

I often simulate outside the required operating range of circuits just to make sure it isn't close to failing.

The temperature range you mention is normally for storage rather than operation, but it could be used for some 'absolute maximum' ratings i.e. the chip isn't expected to work fully, but shouldn't self destruct.

Keith

 

[satheeshvelu]

Hi Keith,

I had a great expectation before knowing the answer that I'm going to know something new.

But unfortunately, nothing new it was.

We always used to do the measurement for the Storage Temperature range (eg. -40 to +125)

But we do test the ICs at temperatures more that that which are only for our internal testing.

The IC would able to operate well in the Operating Temperature Range. (We have to guarantee this spec in the datasheet)

The IC would be tested for the storage temperature range as well. (We don't have to guarantee this spec, but have to be mentioned in the datasheet)

IC would also be tested beyond the storage temperature range. But this will not mentioned in the datasheet, as it is for our internal testing.

I was cracking with my head, as I thought there would be something interesting behind it.

But there was nothing special in it.

Satheesh