Multimeter - integrated circuit detection method
1. offline measurement
Off-line measurement When the integrated circuit is not welded into the circuit, the DC resistance value between its pins is measured and compared with the known normal DC resistance value between the pins of the same type of integrated circuit to determine whether it is normal . 2. online measurement
3. Substitution method
4. total current measurement
One point must be paid attention to when measuring. Since there are a large number of non-linear components such as triodes and diodes inside the integrated block, it is not possible to judge whether it is good or not by only measuring a resistance value during the measurement. Two resistance values. Only when the positive and negative resistance values in R meet the standard, can it be concluded that the integrated block is intact.
According to the actual maintenance experience, when detecting the DC equivalent resistance inside the integrated circuit, it is not necessary to solder the integrated block from the circuit. It is only necessary to disconnect the pin with abnormal voltage or on-line resistance from the circuit, and at the same time connect the grounding pin to the circuit. The board is disconnected, and the other pins remain in their original state. The positive and negative resistance values in R between the test pin and the ground pin can be measured to judge whether it is good or bad.
