HI
My customer has some test about the transient output over current.
the circuit is as below:
over current: 105.6A
duration：720us
times of repetition：50130
interval time: 2250s
the peak current is beyond the largest current of the short-circuit duration curve whick is show in datasheet:
Can INA253 withstand in this situation?
is there any calcualation which can prove the conclusion？
THX~
Hello valued engineer,
Thanks for your question. Unfortunately I do not think I can make a conclusion as to whether the device can safely tolerate this short-circuit condition based off extrapolating the following curve. To start, the curve in the datasheet is actually showing the current level at which the device becomes permanently damaged (blows up). There is another curve that will represent the current which begins to change the resistance of the internal resistor (see below).
Secondly, even when using the green curve, extrapolating backwards is not robust method since it make assumptions that may not be entirely accurate. Real data will always be more accurate.
Thirdly, the short circuit curves are based off of square waves, while your situation shows a triangular so it is not a true 1-1 comparison.
Lastly, the layout of the conducting pads for INA253 will also be another factor.. The bigger the pad, the more heat that can be dissipated throughout and less stress on the INA253.
Overall, the best way to verify this application is to test it in the end application. A good test it to measure the accuracy of the INA253 with a known, accurate and precise DC current level before and after the short circuit test. The short circuit test should be done at the worst-case temperature and for a statistically significant number of samples. It is even better if the amplitude of the short-circuit current can be controlled and started from a low level and incrementally increased until change to the internal resistor is observed.
Hope this helps.
Sincerely,
Peter
