What is a magnetic sensitive transistor, its structure, characteristics, principles, applications, discrimination, and operating procedures 2

4、 Application:

The application of magnetic sensitive transistors is very extensive. In computer hard disk drives, they are used as key components of read-write heads; In automotive electronic systems, they are used to detect the rotational speed of the wheels; In industrial automation equipment, they are used as position sensors; In consumer electronics, they are used to detect the movement and orientation of devices.

5、 Discrimination:

Magnetic sensitive transistors are made of germanium or silicon materials. It is made of P-N structure on high resistance semiconductor material, and a layer of lattice is destroyed on one side of the emission region by sandblasting or other methods, forming a high carrier recombination region. The component adopts a flat plate structure, with the emitter and collector regions located on its upper and lower surfaces. transistors

Select the R * 100 (or R * 1K) ohm range. First, connect the red probe to one pin and the black probe to the other pin to measure two resistance values. Then, connect the red probe to the other pin and repeat the above steps to measure another set of resistance values. Repeat this process three times, and there is a set of two resistance values that are both very small. The red probe corresponding to this set of values is connected to the base, and the transistor is PNP type; On the contrary, if a black probe is connected to a pin and the above method is repeated, if both resistance values are measured to be small, the corresponding black probe is the base and the tube is NPN type. transistors

Because when the emitter and collector of a transistor are correctly con nected, β is larger (the pointer swings more), and when they are reversed, β is much smaller. Therefore, let's assume a collector connected in ohms range (for NPN transistors, connect the emitter to the black probe and the collector to the red probe). When measuring, hold the base and the assumed collector with your hand. The two poles should not be in contact. If the pointer swings greatly and the pointer swings less after swapping the two poles, it indicates that the assumption is correct, and the collector and emitter are determined accordingly. transistors