Background :
Customer shared : Set shutdown during working, display abnormal. Swap test completed as below. customer chamber reproducing evaluation – IC shutdown occurred since OTP(Over Temperature Protection) working after 1 hour (Power off after Error detection observed). When Swap test completed, no OTP occurred and worked well during 48hours with same configuration.
Then what’s fail regarding value: issue IC seems lower temp (116C) than normal IC (128C). The problem is return IC shut down due to OTP even temperature of return IC is lower than correlation IC. Other functions working well.
- Customer condition : Ta = 70C, Tc=125C
- TI(JDAO) initial verification : No anomaly was observed on 125C. normal output observed.
In Datasheet : 145C is shutdown temp but want to know actual standard if it has variation.
Question for next step.
Case/board temperature will not represent junction temperature and that what will cause thermal shutdown. Typical thermal shutdown of this device 145C and can be even less.
TI need more information to understand
1) How customer measure case/board temperature, are they using thermal camera?
This important, because board temperature typical hard to measure using thermal camera as it is not very focus and not very accurate. But if is board temperature, that is different and should be less than case.
2) Please provide more detail on how they do this measurements so we can estimate the junction accordingly.
What is VIN, VOUT, IOUT conditions in which this is happening? I can estimate the junction temperature from either the board ort case temperature.
