What is a chip transistor? The basic function of the SMD triode is to amplify, it can amplify the weak electrical signal to a certain intensity, of course, this conversion still follows the energy conservation, it just converts the energy of the power supply into the energy of the signal.

SMD transistor pin identification formula

One, three upside down, find the base

According to the different connection methods of the two PN junctions, it can be divided into two types of chip transistors with different conductivity types: NPN type and PNP type. To test the SMD triode, use the ohm gear of the multimeter, and select the R×100 or R×1k gear.

For analog multimeters, the red test pen is connected to the negative electrode of the battery in the watch, and the black test pen is connected to the positive electrode of the battery in the watch.

2. PN junction, fixed tube type

After finding the base of the chip triode, we can determine the conductivity type of the tube according to the direction of the PN junction between the base and the other two electrodes. Touch the black test lead of the multimeter to the base electrode, and the red test lead to any one of the other two electrodes, if the pointer of the meter is deflected by a large angle.

Three, along the arrow, the deflection is large