Basic concept of : Metal-oxide-semiconductor field-effect transistors (MOSFETs)

1. About Mosfet

Field Effect Transistor Mosfet's (M etal O F ield E Xide S emiconductor ransistor ffect T) is a special Transistor geometry and other operations with conventional transistors, which I already knew, Mosfet with active principles based on performance applications from schools to generate electricity, the components have large input impedance prefer to amplify the weak signal sources, Mosfet is used extensively in the power circuit monitor, computer source.

Field Effect Transistor Mosfet

2. Structure and symbols of Mosfet.

Symbols and pinout equivalent
Between Mosfet and Transistor

* Composition of the Mosfet.

Channel Mosfet vice composed of P

• 
  
  G: Gate called the gate


• 
  
  S: Source pole called source


• 
  
  D: Drain called drain


• 
  
  Mosfet cocoon N have two pieces of semiconductor type P placed on the semiconductor N, the two layers are insulated by a layer PN SiO 2 two pieces of semiconductor P is connected to the positive pole D and S, N semiconductor platform is connected to thin layer above then into positive sign G.


• 
  
  Mosfet resistor between the pole S pole G and between G with pole pole D is extremely large, and the resistance between the extreme poles D and S depend on the voltage difference between the extreme poles G and S (U GS)


• 
  
  When the voltage U GS = 0, the resistor R DS very large, the voltage U GS> 0 => magnetic effects caused by resistor R DS makes decrease, the voltage U GS greater the smaller the resistor R DS .

3. Operating principle of Mosfet

Test circuit.

Experiment card activity Mosfet

• 
  
  Experiment: DC Power U D over a lightbulb D at D and S poles of Mosfet Q (Conveniently for Mosfet reverse polarity) we see no light bulb means that no current through the leg pole DS G do not have electricity.


• 
  
  When the switch K1 closed, the source U G GS poles inlet voltage U GS> 0V => Q1 led light => light bulb D.


• 
  
  When K1 disconnect switch, voltage across the capacitor C1 area (ceramic capacitor) maintains the lamp Q guide => demonstrate no positive current through GS.


• 
  
  When the switch K2 is closed, integrated voltage across the capacitor C1 decreased by 0 => U GS = 0V => light off


• 
  
  => From the above experiments it was found that: the voltage applied to pins do not generate G GS lines as in conventional transistors, but this voltage is only generated magnetic field => resistor R DS makes reduced.

4. Measure check Mosfet

• 
  
  A Mosfet is better: As the impedance between G and S and between G and D with resistance equal to infinity (needles to measure both directions) and when G has been freed, the electrical impedance between D and S is infinity.

Check the following steps:

Measure check Mosfet see better backwards.

• 
  
  Step 1: Prepare to scale x1K W


• 
  
  Step 2: Go to G one charge (to the black in G que que red in S or D)


• 
  
  Step 3: After loading the G an electric charge is measured between D and S (D que que red to black in S) => needles going up.


• 
  
  Step 4: Short-G to D or G to S to exit power vacuum G.


• 
  
  Step 5: After power vacuum drainage DS G measured as step 3 needles up.


• 
  
  => The result is so good Mosfet.

Measure test shows a short, reverse Mosfet

• 
  
  Step 1: To watch ladder x 1K W


• 
  
  Between G and S measured between the G and D or if the needle up = 0 W is short


• 
  
  Measured between D and S which both dimensions measure up = 0 W alloy is short-DS

5. The application of Mosfet in practice

Mosfet in pulsed source of Monitor

Mosfet is used as a source of light Monitor

In the pulsed source of Monitor or computers, people often use pairs of IC components is Mosfet oscillators and lights, ranging from IC can generate square pulses are brought to the foot of the Mosfet G, at the time of pulse voltage> 0V => Mosfet light guide, the pulse oscillation = 0V Mosfet interrupt => Such oscillations generated will control for continuous switching Mosfet formed continuously variable electric current running through the primary winding => generate varying magnetic field induction to the secondary coil => for the output voltage us.

* Measure check Mosfet circuit.
When checking in-circuit Mosfet, we just need to scale x1 W and measure between D and S => If 1 clockwise to reverse the needle does not measure up => is normal Mosfet, if both clockwise up = 0 W is Mosfet short-DS.

6. Mosfet common lookup table

Instructions:

• Channel type: P-Channel: the agreement Mosfet, N-Channel Mosfet is reverse.


• Specification: Example: 3A, 25W: Maximum DS line and maximum capacity.

STT	Notation	Channel type	Specification
1	2SJ306	P-Channel	3A, 25W
2	2SJ307	P-Channel	6A, 30W
3	2SJ308	P-Channel	9A, 40W
4	2SK1038	N-Channel	5A, 50W
5	2SK1117	N-Channel	6A, 100W
6	2SK1118	N-Channel	6A, 45W
7	2SK1507	N-Channel	9A, 50W
8	2SK1531	N-Channel	15A, 150W
9	2SK1794	N-Channel	6A, 100W
10	2SK2038	N-Channel	5A, 125W
11	2SK2039	N-Channel	5A, 150W
12	2SK2134	N-Channel	13A, 70W
13	2SK2136	N-Channel	20A, 75W
14	2SK2141	N-Channel	6A, 35W
15	2SK2161	N-Channel	9A, 25W
16	2SK2333	N-FET	6A, 50W
17	2SK400	N-Channel	8A, 100W
18	2SK525	N-Channel	10A, 40W
19	2SK526	N-Channel	10A, 40W
20	2SK527	N-Channel	10A, 40W
21	2SK555	N-Channel	7A, 60W
22	2SK556	N-Channel	12A, 100W
23	2SK557	N-Channel	12A, 100W
24	2SK727	N-Channel	5A, 125W
25	2SK791	N-Channel	3A, 100W
26	2SK792	N-Channel	3A, 100W
27	2SK793	N-Channel	5A, 150W
28	2SK794	N-Channel	5A, 150W
29	BUZ90	N-Channel	5A, 70W
30	BUZ90A	N-Channel	4A, 70W
31	BUZ91	N-Channel	8A, 150W
32	BUZ 91A	N-Channel	8A, 150W
33	BUZ 92	N-Channel	3A, 80W
34	BUZ 93	N-Channel	3A, 80W
35	BUZ 94	N-Channel	8A, 125W
36	IRF 510	N-Channel	5A, 43W
37	IRF 520	N-Channel	9A, 60W
38	IRF 530	N-Channel	14A, 88W
39	IRF 540	N-Channel	28A, 150W
40	IRF 610	N-Channel	3A, 26W
41	IRF 620	N-Channel	5A, 50W
42	IRF 630	N-Channel	9A, 74W
43	IRF 634	N-Channel	8A, 74W
44	IRF 640	N-Channel	18A, 125W
45	IRF 710	N-Channel	2A, 36W
46	IRF 720	N-Channel	3A, 50W
47	IRF 730	N-Channel	5A, 74W
48	IRF 740	N-Channel	10A, 125W
49	IRF 820	N-Channel	2A, 50W
50	IRF 830	N-Channel	4A, 74W
51	IRF 840	N-Channel	8A, 125W
52	IRF 841	N-Channel	8A, 125W
53	IRF 842	N-Channel	7A, 125W
54	IRF 843	N-Channel	7A, 125W
55	IRF 9610	P-Channel	2A, 20W
56	IRF 9620	P-Channel	3A, 40W
57	IRF 9630	P-Channel	6A, 74W
58	IRF 9640	P-Channel	11A, 125W
59	IRFI 510G	N-Channel	4A, 27W
60	IRFI 520G	N-Channel	7A, 37W
61	IRFI 530g	N-Channel	10A, 42W
62	IRFI 540G	N-Channel	17A, 48W
63	IRFI 620	N-Channel	4A, 30W
64	IRFI 630g	N-Channel	6A, 35W
65	IRFI 634G	N-Channel	6A, 35W
66	IRFI 640G	N-Channel	10A, 40W
67	IRFI 720G	N-Channel	3A, 30W
68	IRFI 730G	N-Channel	4A, 35W
69	IRFI 740G	N-Channel	5A, 40W
70	IRFI 820g	N-Channel	2A, 30W
71	IRFI 830G	N-Channel	3A, 35W
72	IRFI 840G	N-Channel	4A, 40W
73	IRFI 9620G	P-Channel	2A, 30W
74	IRFI 9630G	P-Channel	4A, 30W
75	IRFI 9640G	P-Channel	6A, 40W
76	IRFs 520	N-Channel	7A, 30W
77	IRFs 530	N-Channel	9A, 35W
78	IRFs 540	N-Channel	15A, 40W
79	IRFs 620	N-Channel	4A, 30W
80	IRFs 630	N-Channel	6A, 35W
81	IRFs 634	N-Channel	5A, 35W
82	IRFs 640	N-Channel	10A, 40W
83	IRFs 720	N-Channel	2A, 30W
84	IRFs 730	N-Channel	3A, 35W
85	IRFs 740	N-Channel	3A, 40W
86	IRFs 820	N-Channel	2A-30W
87	IRFs 830	N-Channel	3A-35W
88	IRFs 840	N-Channel	4A-40W
89	IRFs 9620	P-Channel	3A-30W
90	IRFs 9630	P-Channel	4A-35W
91	IRFs 9640	P-Channel	6A-40W
92	J177 (2SJ177)	P-Channel	0.5A-30W
93	J109 (2SJ109)	P-Channel	20mA, 0.2W
94	J113 (2SK113)	P-Channel	10A-100W
95	J114 (2SJ114)	P-Channel	8A-100W
96	J118 (2SJ118)	P-Channel	8A
97	J162 (2SJ162)	P-Channel	7A-100W
98	J339 (2SJ339)	P-Channel	25A-40W
99	K30A / 2SK304 / 2SK30R	N-Channel	10mA, 1W
100	K214 / 2SK214	N-Channel	0.5A, 1W
101	K389 / 2SK389	N-Channel	20mA, 1W
102	K399 / 2SK399	N-Channel	10-100
103	K413 / 2SK413	N-Channel	8A
104	K1058 / 2SK1058	N-Channel
105	K2221 / 2SK2221	N-Channel	8A-100W
106	MTP6N10	N-Channel	6A-50W
107	MTP6N55	N-Channel	6A-125W
108	MTP6N60	N-Channel	6A-125W
109	MTP7N20	N-Channel	7A-75W
110	MTP8N10	N-Channel	8A-75W
111	MTP8N12	N-Channel	8A-75W
112	MTP8N13	N-Channel	8A-75W
113	MTP8N14	N-Channel	8A-75W
114	MTP8N15	N-Channel	8A-75W
115	MTP8N18	N-Channel	8A-75W
116	MTP8N19	N-Channel	8A-75W
117	MTP8N20	N-Channel	8A-75W
118	MTP8N45	N-Channel	8A-125W
119	MTP8N46	N-Channel	8A-125W
120	MTP8N47	N-Channel	8A-125W
121	MTP8N48	N-Channel	8A-125W
122	MTP8N49	N-Channel	8A-125W
123	MTP8N50	N-Channel	8A-125W
124	MTP8N80	N-Channel	8A-75W