EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

43
EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers

Transcript of EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

Page 1: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

1

Chapter 6. Building blocks of inte-grated-circuit amplifiers

Page 2: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

2

1. IC design philosophy2. Basic gain cell3. Cascode amplifier4. IC biasing5. Current mirror6. Useful transistor pairings

Contents

Page 3: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

31. IC design philosophy

• Large R, L, C should be avoided → minimize chip area• DC supply voltage in the range of 1V.

Page 4: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

4Exemplary chip layout-TL431

Page 5: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

5Ideal biasing (Rbias→∞)

이상적인 바이어스 회로인 경우 active load 의 저항이 무한대 .

R

Page 6: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

62. Basic gain cell

저항보다 트랜지스터 쓰는 것이 면적에서 유리 .

DSV

DI

DI

Active loaded CS amplifier

02

1slope

r

or

Page 7: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

7

1or

2or

)||( 21 oomi

oV rrgA

Voltage gain of current-source load

SR

LR

Page 8: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

8Increasing the gain of the basic cell

Current buffer

Page 9: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

9

)1( omSoo rgRrR

om

L

mom

Loin rg

R

grg

RrR

1

1

1

Input/output impedance of a common gate amplifier

6.3 Cascode amplifier

L

Lin

RD

C

RB

A

I

VR

1

1

S

So CRA

DRB

I

VR

2

2

1011

1

om

o

omcg

rg

r

rgDC

BA

Common gate 로 연결된 drain 에서 본 source impedance 는 원래보다 (1+gmro) 배 커짐 .

Common gate 로 연결된 source 에서 본 source impedance 는 원래보다 (1+gmro) 배 작아짐 .

MOS cascode

Page 10: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

10MOS cascode

Common source

Common gate

CS 증폭기에 CG 증폭기 연결하면 output impedance 는 원래보다 (1+gmro) 배 커짐 .

2d

imG

outR

To load

Page 11: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

11

001

)1(1

)1(

1

00

1

1

1

)1(

1

1011

1

00

11

22

2212

112211

122

2

112211

22

2

22111

om

omoo

omomom

mom

o

omomom

om

o

ommomtotal

rg

rgrr

rgrgrg

grg

r

rgrgrg

rg

r

rggrgDC

BA

Common source Common gate

122122212221 )1( oomoomooomooS

Sout rrgrrgrrrgrr

A

B

CRA

DRBR

)||(/1/11

/

/11

1

2Loutm

Lout

m

LL

in

out RRGRR

G

RBA

B

RB

AV

VA

11222

2211

1

2

)1(

111m

oomo

omom

Lin

outm g

rrgr

rgrg

BBARV

IiG

221221 BIIARVBIAVV L

)0( SR

)0( LR

Calculation of cascode design parameters (ABCD)

CS, CG 두 형태의 ABCD 파라미터로 계산

Trans-conductance :

Output impedance :

Voltage gain :

Page 12: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

12Trans-conductance (Gm) of a cascode amplifier

SR

)(/

1)(

112121

22

22222

oimogsogsimo

gso

mogsogsmo

igrrgi

rgirgi

1

2

112

12

112

112

22

11211

22

1

11)(

1

m

o

oom

mo

oom

i

oi

imoo

moo

oomoimo

omo

g

rr

rg

grr

rgi

G

grr

gir

rrgigr

rgi

Page 13: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

13

1112

2222

)(

)(

oooimogs

ogsogsmo

rirgi

rgi

)0( i

12212221

1222

)(

)1(

oomoomooout

ooomoo

rrgrrgrrR

irrgr

Output impedance of a cascode amplifier

Page 14: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

14Cascode amplifier with a cascode current-source load

])[(||])[(

)||(

4331221

1

oomoomm

oponmi

o

rrgrrgg

RRgA

Page 15: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

153.5 Double cascoding

Figure 7.15 Double cascoding.Figure 7.16 The folded cascode.

(VDD 를 낮추기 위해 )

Page 16: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

16

Input/output impedance of a common base amplifier

L

Lin

RD

C

RB

A

I

VR

1

1

e

eo CRA

DRB

I

VR

2

2

Common base 로 연결된 collector 에서 본 source impedance 는 원래보다 (1+gmro) 배 커짐 .

Common base 로 연결된 emitter 에서 본 source impedance 는 원래보다 (1+gmro) 배 작아짐 .

)1(//1

1

)1(

1

omo

o

omcbrgrrr

r

rgDC

BA

)||)(1( eomoo RrrgrR

om

Le

L

e

o

Lo

Lom

o

L

o

in rg

Rr

rR

rr

Rr

Rrg

rr

r

Rr

R

1111

1

1

3.7 BJT cascode

mg

or

E

B C

r

Page 17: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

17

out

Common emitter

Common base 2c

imG

outR

To load

CE 증폭기에 CB 증폭기 연결하면 output impedance 는 원래보다 (1+gm2ro2) 배 커짐 .

BJT cascode

Page 18: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

18

)||)(()||)(1( 212221222 rrrgrrrgrA

B

CRA

DRBR oomoomo

S

Sout

)||(/1/11

/

/11

1

2Loutm

Lout

m

LL

in

out RRGRR

G

RBA

B

RB

AV

VA

121222

21221

1

2

)||)(1(

)||)(1(11m

oomo

oomm

Lin

outm g

rrrgr

rrrgg

BRBV

IiG

221221 BIIRVBIAVV L

)0( SR

)0( LR

Trans-conductance :

Output impedance :

Voltage gain :

2221

2

1211

2221

2

1211

22

22222

2

111

111

22

1||

1

)||(

1

1||

1

)||(

1

)1(

1

)1(//1

111

11

)1(

1

omo

o

o

omo

o

mom

om

omo

o

o

mom

omcas

rgrr

r

rr

rgrr

r

grrg

rg

rgrrr

r

r

grgrgDC

BA

Calculation of cascode design parameters (ABCD)

CE, CB 두 형태의 ABCD 파라미터로 계산

Page 19: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

19

Figure 6.19 A BJT cascode amplifier with a cascode current source.

Page 20: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

204. IC biasing

2

11 )(

2

1tnGSnD VV

L

WkI

R

VVII GSDD

REFD

1

2

22 )(

2

1tnGSnDO VV

L

WkII

1

2

)/(

)/(

LW

LW

I

I

REF

O

MOS current mirror

GSV

DI

tnV DDV

R

VDD

VDD 와 R 을 이용하여 Q1 의 VDS 를 고정하여 Q2 를 전류원으로 만들 수 있다 . VO 가 변해도 전류는 고정 .

Page 21: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

21

om

rg

||1

1

1

||1

om

rg

gsgsmg

or

D

ds

gsgsmg

or

G

ds ormg

1

Small signal equivalent circuit

Page 22: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

22

Figure 6.23 Basic MOSFET current mirror. Figure 6.24 Output characteristic of the current source

21

2 1)/(

)/(

A

GSOREFO V

VVI

LW

LWI

)( tnGSOVO VVVV

Page 23: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

23Current-steering circuits

1

22 )/(

)/(

LW

LWII REF

1

343 )/(

)/(

LW

LWIII REF

4

543 )/(

)/(

LW

LWII

Page 24: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

244.3 BJT current mirror

CI

CCCREF IIII

21/2

2

1

1

21

C

C

REF

O

I

I

I

I

Page 25: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

25

2r11 || oe rr

2

22 mg

2or

D

ce

mg

or

G

ce ormg

1

r r orer

Small signal equivalent circuit

Page 26: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

26Simple BJT current mirror

A

BEOREFO V

VVII 1

)/2(1

R

VVI BECC

REF

Figure 6.31 Generation of a number of constant currents of various magnitudes.

R

VVVVI BEEBEECC

REF21

Page 27: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

275. Improved current-mirror circuits

233 )( oomo rrgR

Cascode current-mirror

Current mirror 의 output impedance 는 증가하나 VO 의 최소 출력 전압이 높아서 voltage range 가 좁아지는 것은 단점이다 .

tnOVO VVV 2

GSV

GSV

tnOVGS VVV 222

GSV

11

||1

om

rg

44

||1

om

rg

전압 고정

전압 고정

Page 28: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

28BJT mirror with base-current compensation

22 /21

1

)/(21

1

REF

O

I

I

)1(

21

CREF II

R

VVVI BEBECC

REF31

Page 29: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

29Wilson current-mirror

2/21

1

)1(2

11

)1(2

1

REF

O

I

I

Q3 collector 전류 증가→ Q1 의 베이스 전압 증가 → Q2 의 collector 전류 증가 → Q3 의 베이스 전류 감소 (negative feed-back 임 ).

Page 30: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

30

3r

3

33 mg

3or

x

2 12 || err22 mg

2or

xi

33332

3333

3

3

2

12333 1

/1)(

om

mom

m

eomxx rg

rgrg

rg

rrgi

3

3

2

13

3123

2

223

3

12

233

12

2 1/11

||

11

1

1

||||

rg

r

rrrr

r

rgi

rrrir

rri

m

e

e

o

omx

ex

ex

32

33

3

2

222

33

2222222

3

332

11

1

1)1(

rgr

r

rg

r

rrgrg

r

m

o

om

oomom

33333

32

1

33

2

1

2

1

11

/1oom

m

e

om

x

xo rrrg

rgr

rg

iR

Output impedance B

C

EC

Page 31: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

31

3gs33 gsmg

3or

x

2gs 11

||1

om

rg

22 gsmg 2or

xi

2333 )( gsogsmxx rgi

22222223 )1( gsomgsogsmgs rgrg

1

12 ||

1o

mxgs r

gi

xom

omgsomgs irg

rgrg

1

1222223 ||

1)1()1(

xom

xom

omomxo

gsgsomoxx

irg

irg

rgrgir

rgri

11

11

22333

23333

||1

||1

)1(

23311

22333

11)1( oom

mmomomo

x

xo rrg

ggrgrgr

iR

Wilson MOS mirror

Page 32: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

32Widlar current source

S

OTBE

S

REFTBE I

IVV

I

IVV ln,ln 21

EOO

REFTBEBE RI

I

IVVV

ln21

REFTOTO

REFTEO IVIV

I

IVRI lnlnln

OI

V

REFI

EORI

oEmoEomoout rrRgrrRrgrR )]||(1[)||(

Q1, Q2 의 전류 비율이 크고 작은 저항으로 해결하기 위함 .

O

REFT I

IV ln

Page 33: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

33Example 6.6

The two circuits for generating a constant current IO = 10 μA shown in Fig. 7.37 oper-ate from a 10-V supply. Determine the values of the required resistors, assuming that VBE is 0.7 V at a current of 1 mA and neglecting the effect of finite β.

][94201.0

58.010

][58.0][1

][10ln7.0

1

1

kR

VmA

AVV TBE

][5.11

][10

][1ln025.01010ln

][3.9001.0

7.010][1

3

36

3

2

kR

A

mAR

I

IVRI

kRmAI

O

REFTO

REF

Page 34: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

346. Some useful transistor pairingsFigure 6.38 (a) CC–CE amplifier; (b) CD–CS amplifier; (c) CD–CE amplifier.01

1bi

11 bi

1or

E

B C

1r

2or

E

B C

2r

))(1( 11 inein RrR

2rRin

in

in

out

1gs11 gsmg

1or

E

B C

2gs22 gsmg

2or

E

B C

in

LR LR

2bi

22 bi

1112 ogsmgs rg

)||( 222 Logsmo Rrg

211

21

11 gs

omgsgsin rg

Lm

om

Lom

in

o Rg

rg

Rrg2

11

22

11

)||(

Page 35: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

35

212121221

2

1

21

1

2

1

21

1

2

222

222

111

11

1

11

)1(

111

)1(

1

11

11

1

11

11

)1(

1

)1(

1

1

omomo

e

mo

ee

mo

e

o

o

mom

o

eo

e

rgrgr

r

gr

rr

gr

r

r

r

grg

r

rr

r

DC

BA

)||)(1(11

111

11

1111

)1(1111

)1(1

1111

2111

21

2111

212

22111

1

22121

22

1

21

1

rrr

rr

rrrr

rg

grrr

Rrrg

Rrr

grr

RD

C

RB

AZ o

o

oe

om

moee

Loom

Lo

e

mo

e

L

Lin

)||()||(

)||(

111111111

122

211

21

22111

2

22

2

111

2Lom

oe

o

Looee

m

Lo

m

oee

m

L

Rrgrrr

rr

Rrrrrr

g

Rrg

rrr

g

RB

AA

CC–CE amplifier

111 mg

1or

E

B C

1r

222 mg

2or

E

B C

2r

Common collector

Common emitter

Page 36: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

36

][5.222 krRin 111 )1( rrRin

]/[155)160(99.098.0

)||( 2212

2

1

VV

RrgrR

R

RR

RA Lom

ein

in

insig

in

b

o

Example 6.7Find Rin, overall voltage gain. (I1=I2=1 [mA], β = 100 , Rsig = 4 kΩ, RL = 4 kΩ, ignore ro)

][5.2],[25

],/[4021

krrg

r

VmAV

Igg

em

e

T

Cmm

][2555.2525.2)1( 111 kkkrrRin

Page 37: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

37

01.00

251

)1(

1

)1(

1

1

o

eo

e

CC

r

rr

r

DC

BA

01.00

25011

11

o

mom

CE

r

grgDC

BA

410.10

25.250

01.00

250

01.00

251

totalDC

BA

]/[4.158

425.25

0

11VV

kRB

AA

L

in

out

),( 21 oo rr

1V

2V

2I1I

DC

BA

2

2

1

1

I

V

DC

BA

I

V

L

in

out

RB

AV

VA

1

1

2

22 IRV L

21221 VR

BAVBIAVV

L

Page 38: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

38Darlington configuration

21

111 mg

1or

E

B C

1r

222 mg

2or

E

B C

2r

))(1( 22 Eein RrR

))(1( 11 inein RrR

LR

높은 β 값을 갖는 BJT 역할함 .

Q1 의 β 값이 DC bias current I 에 의존 .

Page 39: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

39

111 mg

1or

E

B C

1r

222 mg

2or

E

B C

2r

)1(

1

)1(

1

)1()1(

1

)1(

11

)1(

1

)1(1

)1(11

)1(

1

)1(

1

)1()1(

1

)1(

11

)1(

1

)1(1

)1(11

)1(

1

)1(

1

1

)1(

1

)1(

1

1

2111

2

2212

2

11

2

12

1

1

22

1

2

2

1

1

2111

2

2212

2

11

2

12

1

1

22

1

2

2

1

1

222

22

2

111

11

1

o

e

oo

e

o

ee

o

e

o

e

o

e

o

e

o

e

oo

e

o

ee

o

e

o

e

o

e

o

e

o

eo

e

o

eo

e

r

r

rr

r

r

rr

r

r

r

r

r

r

r

r

r

r

rr

r

r

rr

r

r

r

r

r

r

r

r

r

rr

r

r

rr

r

DC

BA

LR

Page 40: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

40

Lo

e

oo

e

o

L

ee

o

e

o

e

o

e

o

e

L

Lin

Rrr

rrr

r

Rr

rrr

rr

rr

rr

RD

C

RB

AZ

1)1(

1)1(

1)1()1(

1)1(

11

)1(1

1)1(

1)1(

11

2111

2

2212

2

11

2

12

1

1

22

1

2

2

1

1

CC–CC amplifier

)]||()[1(||)1(

)]||()[1(

)]||()[1()]||()[1()1(

)]||()[1(

)]||()[1()1(

11)1(

1111

11)1(

111111

)1(

222111

1222

2221122211

1222

11222111

22221

2

2222112

11

Loeoe

oLoe

LoeoeLoeo

oLoe

eoLoeeo

LoLoeo

e

LoLoeoee

e

Rrrrr

rRrr

RrrrrRrrr

rRrr

rrRrrrr

RrRrrrr

RrRrrrrr

r

)1)(1()]||()[1(

)||)(1(1)1(

11)||)(1(

)/()||)(1)(1(

1111

)1)(1(

11

)1)(1(

11

)1)(1(

1111

)1)(1(

)1(1

)1(1

)1()1(1

)1(1

1)1(

1

11

21221

1221

2121

22

2221

2212

21

2

21

21

2

21

2

21

1

2

1

2

221

2

21

1

2

2221

2

21

2111

2

2212

2

11

Loeo

oLo

L

oo

Lo

LLo

oLoL

e

L

oo

L

oe

L

o

ooo

L

e

L

ooL

ooeo

o

eL

oo

e

o

Li

Rrrr

rRr

R

rrrrRr

rRRr

rRrrrR

rR

rr

rR

rr

rR

rr

rr

rr

rR

rR

rr

rr

Rrrrr

r

rr

Rrr

rr

DCRA

Page 41: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

41

1

)||(

)||(

)||)(1(||

)||)(1(||

)||)(1()||)(1(

)||)(1(

)||)(1(1

)||)(1(

)||)(1(||11

1

1)1(

1)1(

11

11

22

2

22211

2221

22222211

1

22

2221

11

22

22

1

2

2

1

1

2

12

1

1

22

1

2

2

1

1

Loe

Lo

Looe

Loo

LoLooo

e

Lo

Loo

ee

Lo

Lo

e

Lo

e

o

e

L

ee

o

e

o

e

o

e

o

e

L

Rrr

Rr

Rrrrr

Rrrr

RrrRrrrrr

Rr

Rrrrr

r

Rr

Rrr

Rrr

rr

Rr

rrr

rr

rr

rr

RB

AA

Page 42: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

42CC–CB amplifier

Page 43: EMLAB 1 Chapter 6. Building blocks of integrated-circuit amplifiers.

EMLAB

43

1

11 mg

1or

E

B

C

1er

2

22 mg

2or

E

BC

2er

Example 6.8