第六章場效電晶體場效電晶體 2015-3-5

8/18/2019 2015-3-5

1/20

- 1 -

:

§ 6-1

(FET) (BJT)

1 BJT FET

1 BJT (BJT )

2 FET (FET )

NOTE BJT npn pnp FET n- p-

2 FET

1 1MΩ~ MΩ

2 FET BJT

3 FET BJT

4 FET

3 FET

1 JFET Junction Field-Effect Transistor

2 MOSFET

Metal-Oxide-Semiconductor Field-Effect Transistor

D-MOSFET n-ch p-ch

E-MOSFET n-ch p-ch

3 MESFET

Metal-Semiconductor Field-Effect Transistor

8/18/2019 2015-3-5

2/20

- 2 -

§ 6-2 JFET

n- JFET

1 JFET n- p-

n-

2 JFET

(drain;D) (source;S) n-

(gate;G) p

JFET

JFET

1

( ) ( )

2 ( ) ( )FET

S D ( G)

JFET

1 S D 2 G-S , VGS

JFET

1 VGS=0

(1) VDS , VDS ID

(2) VDS , VDS VDG D-G

(

) ID

n-

n-

n-

n-n-

8/18/2019 2015-3-5

3/20

- 3 -

(3) VDS , VDG ID

ID ID IDSS VDS VDS(sat)

( VDG 4V )

(4)

VDG 4V VDG VDS VGS VGS=0

VDS 4V VDS(sat) 4V

2 VGS≠0

1 VGS= - 1V

8/18/2019 2015-3-5

4/20

- 4 -

VDG VDS VGS 4= V DS ( 1)

VDS 3V VDG 4V VDG

VDS(sat) 3V

2 VGS= - 2V

VDS 2 VDG 4V VDS(sat) 2V

3 VGS= - 3V


4 VGS= - 4V


VDS 0 ID 0 OFF VGS VGS(OFF) VP

VDS(sat) - Vp+ V GS

VGS =0 ID IDSS ( )

1

2

21

)(2 DS DS t GS D V V V V K I

2 ( BJT )

1 2t GS D V V K I

22

1

P

GS

DSS DV

V I I

2 P

DSS

V

I K P t V V

8/18/2019 2015-3-5

5/20

- 5 -

p- JFET

1 n- p- n-

2 ID VGS

3 VDS 0 VGS ID

V G S

= V P

=+6V

I D SS

V G S

= V P

=+6V

I D SS

V G S

= V P

=+6V

I D SS

1 p-n IG

2 n-

n- p-n- p-

8/18/2019 2015-3-5

6/20

- 6 -

§ 6-3

1 ID VGS

2 FET ( V GS ) ( ID )

NOTE ( )

(Shockley’s) 2

1

P

GS

DSS D

V

V I I

3

1

① VGS 0V , ID IDSS

② VGS VP , ID 0

2

IDSS VP

2

1

P

GS

DSS DV

V I I

① VGS 0V , ID IDSS

② VGS VP , ID 0

①①

②

①

②

②

←

(

)

↓

①①

②

①

②

②

①①

②

①

②

②

←

(

)

↓

8/18/2019 2015-3-5

7/20

- 7 -

③ VGS 1/2V P , ID 1/4I DSS

④ VGS 0.3V P , ID 1/2 I DSS

NOTE FET FET

6.1 IDSS 12mA VP = -6V

① V GS 0V , ID IDSS 12 mA

② V GS VP - 6V , ID 0

③ V GS 1/2V P - 3V ,

ID 1/4I DSS 3mA

④ V GS 0.3V P - 1.8V ,

ID 1/2 I DSS 6mA

① ② ③ ④

6.2 IDSS 4mA VP = 3V p-

① V GS 0V , ID IDSS 4 mA

② V GS VP 3V , ID 0

③ VGS 1/2V P 1.5V ,

ID 1/4I DSS 1mA

④ VGS 0.3V P 0.9V ,

ID 1/2 I DSS 2mA

① ② ③ ④

①

②

③

④

①

②

③

④

①

②

③

④

①

②

③

④

8/18/2019 2015-3-5

8/20

- 8 -

VDS 25 Vdc VDG 25 Vdc

VGSR -25 Vdc

IG 10 mAdc

T A=25

℃ 25℃ PD

3102.82

mWmW/℃

TJ 125

℃

Tstg -65 +150 ℃

VDS 25 Vdc VDG 25 Vdc

VGSR -25 Vdc

IG 10 mAdc

T A=25

℃ 25℃ PD

3102.82

mWmW/℃

TJ 125

℃

Tstg -65 +150 ℃

2N545729-04, 5

TO-92 (TO-226AA)

1

3

2

JFETs

N-

2N545729-04, 5

TO-92 (TO-226AA)

1

3

2

JFETs

N-

§ 6-4 JFET

(TA=25℃ )

(I

G= -10 μAdc V

DS= 0)

V (BR)GSS -2.5 Vdc

(V GS= -15Vdc VDS= 0)(V GS= -15Vdc VDS= 0 TA=100℃)

IGSS

-1.0-200

nAdc

(V DS= 15Vdc ID= 10nAdc) 2N5457

VGS(off)VP -0.5 -6.0

Vdc

(V DS= 15Vdc ID= 1 00μAdc) 2N5457

VGS -2.5

Vdc

*

(V DS= 15Vdc Vgs= 0) 2N5457IDSS

1.0 3.0 5.0mAdc

(CH8) *

(VDS= 15Vdc VGS= 0 f =1.0kHz) 2N5457fsy

1000 5000μ mhos

*(VDS= 15Vdc Vgs= 0 f =1.0kHz)

osy 10 50

μ mhos

(VDS= 15Vdc VGS= 0 f =1.0MHz)

C iss 4.5 3.0

pF

(VDS= 15Vdc VGS= 0 f =1.0MHz)

Crss

1.5 3.0

pF

* ≦ 630ms ≦ 10%

8/18/2019 2015-3-5

9/20

- 9 -

V GS = 0V → I D = I DSS

ID = ½ IDSS→ VGS ≅ 0.3V p

ID = 0mA → VGS = V p

1mA3V-2V-

19mA1, -222

P

GS DSS DGS

V

V I I V

( )

→ V GS

= 0V,-0.5V,-1V,-1.5V,-2Vn- ,

--- ?

V GS = 0V → I D = I DSS

ID = ½ IDSS→ VGS ≅ 0.3V p

ID = 0mA → VGS = V p

1mA3V-2V-

19mA1, -222

P

GS DSS DGS

V

V I I V

( )

→ V GS

= 0V,-0.5V,-1V,-1.5V,-2Vn- ,

--- ?

NOTE

1 VGS

2 VGS VDS

§ 6-5

2N4416 JFET

(I Dmax )(I Dmax )

8/18/2019 2015-3-5

10/20

- 10 -

§ 6-6

§ 6-7 MOSFET

1 MOSFET

(Metal-Oxide-Semiconductor Field-Effect Transistor)

2 MOSFET

1 (Depletion type) D-MOSFET

① N-channel D-NMOS

② P-channel D-PMOS

2 (Enhancement type) E-MOSFET

① N-channel E-NMOS

② P-channel E-PMOS

8/18/2019 2015-3-5

11/20

- 11 -

D-NMOS

1 SiO 2

2 SiO 2

3 SiO 2

JFET

4 (drain;D) (source;S) N-

N N

1 VGS G P ” ”

VDS ID

2 VGS G ” ”

VDS ID

( )

( )

( )

n

n

(Sub Strate)

SS P

↓s

( )( )

( )

( )

n

n

(Sub Strate)

SS P

↓s

( )( )

( )

( )

n

n

(Sub Strate)

SS P

↓s

( )

8/18/2019 2015-3-5

12/20

- 12 -

1 VGS=0

(1) VDS , VDS ID

(2) VDS , VDS VGD VGS G ” “ (

) ID

(3) VDS VGD

VDS ID

VDS VDS(sat)

VGD ( ) 4V

NOTE VGD VGS VDS VGS=0 VDS 4V VDS(sat) 4V

2 VGS≠ 0 1 VGS 1V

VDS 3V VGD 4V VDS(sat) 3V

2 VGS 2V


3 VGS 3V

VDS 1V VGD 4V VDS(sat) 1V 4 VGS 4V


NOTE VDS 0 ID 0 OFF VGS

VGS(OFF) VP

VDS(sat) Vp+ V GS

8/18/2019 2015-3-5

13/20

- 13 -

1

2

21


2 ( BJT )

1 2t GS D V V K I

22

1

P

GS

DSS DV

V I I

2 P

DSS

V

I K P t V V

NOTE ( )

1 2t GS D V V K I

22

1

P

GS DSS D

V

V I I

8/18/2019 2015-3-5

14/20

- 14 -

2 P

DSS

V

I K P t V V

§ 6-8 MOSFET( E-MOS)

1 MOSFET

(Metal-Oxide-Semiconductor Field-Effect Transistor)

8/18/2019 2015-3-5

15/20

- 15 -

( n- ) p ( )

(V GS >0)

( n- ) p ( )

(V GS >0)

2 MOSFET

1 (Depletion type) D-MOSFET

① N-channel D-NMOS

② P-channel D-PMOS

2 (Enhancement type) E-MOSFET

① N-channel E-NMOS

② P-channel E-PMOS

E-NMOS

1 MOSFET

(n-

)

2 SiO2

p -

1 G ’ VGS

2 G , ,

n

n VGSVGS(th) V t

V t 1 ~ 3 V

n-

(Sub Strate)

p-

↓s

SS

n-

n-

(Sub Strate)

p-

↓s

SS

n-

n-

(Sub Strate)

p-

↓s

SS

n-

8/18/2019 2015-3-5

16/20

- 16 -

V t = 2V

1 VGS V t ID 0

2 VGS V t

1 VGS = 8 V

① VDS ( VDS = 0.1V 0.2V )

VDS ID

② VDS

VDS ( VDS = 1V) VGD 7V VGS 8V G

D S n ” “

( ) ID

③ VDS (6V) VGD V t = 2V n

D VDS ID

NOTE VDS VDS(sat)

VDS(sat) V t VGS

8/18/2019 2015-3-5

17/20

- 17 -

V DS satV DS sat

VDS(sat) V t VGS

VGS = 8 V VDS(sat) V t VGS 2 8 6V

VGS = 8 V VDS 6V VGD V t = 2V

2 VGS = 7 V

VDS(sat) V t VGS 2 7 5V

VGS = 7 V VDS 5V VGD V t = 2V

3 VGS = 6 V VDS(sat) V t VGS 2 6 4V

4 VGS = 2 V VDS(sat) V t VGS 2 2 0V

VDS 0 ID 0 OFF VGS VGS(th)

V t

1 VGS V t

ID 0

2 VGS V t VGS

VDS(sat) ID

1

2

21


8/18/2019 2015-3-5

18/20

- 18 -

2

2t GS D V V K I

K

NOTE 1

NOTE 2 ID VGS

NOTE 3 2 FET

NOTE 4 BJT

1 ( )

2 E-NMOS

NOTE FET ( ) VDS VDS(sat)

VDS(sat) V t VGS

1

D-S

( )

2

n - p -n - p -

8/18/2019 2015-3-5

19/20

- 19 -

VDS 25 Vdc VDG 30 Vdc* VGS 30 Vdc

ID 30 mAdc@T A=25

℃25℃ PD

3001.7

mWmW/℃

TJ 175 ℃ Tstg -60 ~ +175 ℃

*±75

E-PMOS

( N- MOSFET)

8/18/2019 2015-3-5

20/20

- 20 -

2N435122-03, 2

TO-72 (TO-206AF)

3

42

1

MOSFETs

n-

2N435122-03, 2

TO-72 (TO-206AF)

3

42

1

MOSFETs

n-

NOTE VGS(on) ID(on)

K

2t GS D V V K I 2)(

)(

)( t onGS

on D

V V

I K

1 E-NMOS K=0.25mA/V 2 V t=2V VGS =4V ID= (1).V DS =1V

(2).V DS =10V

Ans

VDS(sat) V t VGS 2 4 2V

(1) VDS =1V VDS VDS(sat) E-NMOS

mAV V V V K I DS DS t GS D 75.05.15.01

21

1)24(5.021

)(2 22

(2) VDS =10V VDS VDS(sat) E-NMOS

mAV V K I t GS D 1)24(

41

)( 22

第六章 場效電晶體場效電晶體 2015-3-5

Documents

第六章場效電晶體場效電晶體 2015-3-5