How to detect a double gate field-effect transistor?
(1) Discriminant electrode and good or bad of the double gate field-effect transistor.
Put the multimeter in the RX 100Ω gear and measure four pins, two of which have both positive and negative resistance, and these feet are D and S. The resistance of the drain (D) and the source (S) is dozens of ohms. When D and S are found, D and S are measured again, in which the measured values are larger, that is, the black pen is connected to the D pole, the red pen is connected to the S pole, the S pole is the signal gate G, and the control gate G2 is close to the D pole. If RX1kΩ or 10kΩ blocks are used, GiD, GIs, G2D, G2s and GIG should be excluded, otherwise they will be bad. In the process of detection, if the resistance between the D and S poles is great, the internal breakage is indicated; if the resistance between the G, the G2 gate and the S (or D pole) and the GI.G2 gate is small or zero, the corresponding electrode is leakage or breakdown.
(2) Detection of double gate field-effect transistor magnification
The multimeter is placed in the RX100kΩ gear, the black pen is connected to the D pole, the red pen is connected to the S pole, which indicates the resistance between the drain and the source, and the resistance value of dozens of ohms; at the same time, the metal rod touches the Gi and Gpoles, when the resistance value should change. The greater the change of resistance, the stronger the magnifying power of the transistor. If the needle does not swing, it means that the transistor has lost its magnifying power.
The points to be paid attention to in the test:
Because the MOS double gate field effect transistor is insulated by a thin oxide between S and D, it is necessary to avoid measuring under strong electric field. Schottky and other models of dual-gate FET can not be measured using a force meter, so as to avoid damage to the pipe caused by electrostatic induction, which can be judged by the substitution method, in the welding, you can keep the original set of plastic pipe or protect the aluminum box does not move, with a thin piece of copper wire in the pipe foot by the root winding, so that the pin is completely in parallel, then cut the pin to the desired length and form an appropriate shape, which is welded like a common transistor. After welding, the fine copper wire is removed, which can prevent the inductive electrostatic high-voltage breakdown damage.
If you want to know more, our website has product specifications for the transistors, you can go to Allicdata Electronics Limited to get more information.