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Measurements >> Other Measurements >> Absolute maximum ratings
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Message started by dandelion on Mar 26^th, 2007, 7:26pm

Title: Absolute maximum ratings
Post by dandelion on Mar 26^th, 2007, 7:26pm

In the commenrcial product datasheet, it always gives the "absolute maximum rating" which describe the risks when the product operate exceeeding this limt.

My question is mainly focused on the definitions on the maximum absolute ratings of the supply voltage and input(output) voltage.

I do understand a too high supply voltage could cause an accelerated wear out of devices and a too high and sustained input voltage could cause permanent damage to ESD structures, etc... "

But I have no idea how to quantitatively define it. E.g., how can I know at what high supply will cause an accelerated wear out of devices? Also, I understand too high and sustained input voltage will cause the permanent damage to ESD structures. But I can not know how high this input voltage will have this risks.

Any guidelines to quantitatively define it?

Thanks in advance

Title: Re: Absolute maximum ratings
Post by vincent.ma on Apr 18^th, 2007, 11:03pm

Hi ,all
I also have the similar question that is in practical simulation(Hspice),how to simulate Absolute maximum ratings?

Title: Re: Absolute maximum ratings
Post by krishnap on Apr 24^th, 2007, 11:37pm

One of the factor which decides the maximum ratings is the reliablity limit of the devices.
Usually MOS devices are designed for acheving certain performance criteria like VT, offstate leakage,
current drive etc. Also the normal operating supply voltage is defined based on this.
If the supply voltage applied is more than the normal value.at certain points reliablity limits of the
device will be reached which causes the dmaage to the device.Some of them are like Gate oxide breakdown,
Avalanche breakdown at the drain side and other short channel effects. Also ESD/IO constraints are to be taken care.