When Lenovo after-sales personnel measure the eight-pin chip on the motherboard, they need to determine the test method and specific values according to the chip model and pin function. Under normal circumstances, the test mode of the multimeter will choose different test methods such as resistance, voltage, and current according to the function of the chip pin. Here are some basic testing steps:
1. First of all, it is necessary to determine the chip model and pin function. Generally, you can query the chip manual or search for relevant information on the Internet.
2. Determine the test mode according to the function of the chip pin. For example, if you need to test the input end of the chip, you can use the voltage test mode of a multimeter to measure the voltage by touching the pen to the input end and ground line of the chip.
3. If you need to test the output end of the chip, use the resistance test mode of the multimeter to measure the resistance by touching the output end of the chip and the ground wire respectively.
4. If you need to test the open or short circuit of the chip, you can use the resistance test mode or diode test mode of the multimeter to detect according to the chip pin function.
It should be noted that the specific test method and value will vary according to the chip model and pin function, if you are not familiar with the detection method of the chip, it is best to ask a professional to test.
Is to test whether the path, or whether the output is normal, Lenovo notebook, the normal adapter output is about 19.5V, are considered normal