During the batch use of PCA82C250, several cases of damage to the chip were found。Recently, it was discovered that one case was damaged after SMT。2 cases were damaged after being installed as a complete machine for aging test。Among them, for the NG product's pin entry impedance test, the input is as follows：
| Serial number | TEST | OK(Ω） | NG1(Ω） | NG2(Ω） |
| 1 | 1-2 | 15.3M | 7.03M | 265.1K |
| 2 | 3-2 | 15.7M | 7.07M | 254K |
| 3 | 4-2 | 15.3M | 7.11M | 259K |
| 4 | 5-2 | 13.1M | 11.37M | 263K |
| 5 | 6-2 | OL | 238K | 4.3 |
| 6 | 7-2 | OL | 200K | 43K |
| 7 | 8-2 | OL | 8.45M | 43K |
| 8 | 1-3 | 10.57K | 10.56K | 10.72K |
| 9 | 2-3 | 3M | 3M | 248K |
| 10 | 4-3 | 4.1K | 4.1K | 6.8M |
| 11 | 5-3 | 6.76M | 7.33M | 223K |
| 12 | 6-3 | 6.56M | 3.22M | 41.1K |
| 13 | 7-3 | 6.5M | 3.18M | 213K |
| 14 | 8-3 | 6.7M | 6.72M | 216K |
| 15 | 7-6 | 38.3K | 38.2K | 255K |
| 16 | 6-7 | 38.3K | 38.37K | 248K |
I want to know what caused the CAN chip to be damaged and what I can do to make a more in-depth confirmation.
