After the light-emitting command is given in the OTDR mode, the chip has no light or the lig htemitting time is short. The chip is abnormal at ambient temperature of 25 ° C, and the chip can return to normal when the ambient tempe rature is increased to 55 ~ 65 ° C. The chip is abnormal at 25 °C ~ 75 °C, and the temperature is reduced to-15 °C. The chip has failure at three temperatures.Cross-validation of de fective products to locate chip abnormalities. We did IV test on 2pcs of defective products and found that the pins of AVDD PIN8-AVSS PIN4 8 were abnormal, and then opened the cover for X-ray test and found that the defective pieces had bright spots.
