Electrical Measurements 05 Oscilloscopes

7/22/2019 Electrical Measurements 05 Oscilloscopes

1/36

63

8

5.1

-

, ,

.

,

. , .

.

, -

, -

() GHz.

u(t),

u1(t) u2(t), u1(u2).

.

:

. .

. -

, 30Hz ,

.

.


2/36

64

-

. (cathode ray tube,

CRT). ,

, .

. ,

. , RAM.

, . ,

,

(liquid crystal display, LCD).

5.2

. ,

.

, -

. .

.

.

(). . -

s

.

:

, .

, .

, . ,

, .

,

:

.

.

.

,

. -

, .

,

. 5.1. -

, ,

. , -

.

, ,

.


3/36

. 5. 65

y 1

2

x

x

y

x: o()

y: ()

. 5.1

, ,

, -

. ,

, .-

,

. ,

. ,

, . . 5.1

.

.

-

.

.

, . , ,

.

. ,

, .

.

,

,

.

.

, xy.

. 5.2. lt-

Vt. ,


4/36

66

,

. -

,

2

t t

a

V l L

H V d= (5.1)

, L, d

Va . ,

tan2

t t

a

V lH

L V d = = (5.2)

. (5.2) -

ltd, VtVa

. ,

,

. ,

. 5.2,

.

-

3035. ,

. , -

, .

L

lt

H

d

+

_

Vt

E

()

()

. 5.2 (), ()


5/36

. 5. 67

. ,

-

, . ,

, , -

.

5.3

,

. (divisions),

,

(graticule), . 5.3.

-

. (x) 10 ,

(y), 8 .

1cm.

5.3.1

. -

.

. 5.4, -

. . 5.4

. 4 (1:1, 10:1, 100:1 1000:1),

(1:1, 2:1 4:1). 12 ,

Volts/div.

-x

-y

. 5.3


6/36

68

usw

Time/div.

Flip-Flop

+ _

TimeCAL.

+

_

SLOPE+/-

Line

Triggerselector

AC

DC

HF

LF

External

Trigger

usf

f

ucomp

1:110:1

100:1

1000:1

1:12:14:1

Y-1

INVERTY-Position

Volts/div.

VoltsC

AL.

Y-1

Y-1

Y

Y

X

1:110:1

100:1

1000:1

1:12:14:1

Y-2

Y-Position

Volts/div.

Y-2

Y-2

Chopper

uc

h

ALT./CHOP

Volt

sCAL.

INT./EXT.

TRIG.CH.1-2

Trigg

er

driver1

Trigger

driver2

6

.3Vac

-1900V

-1878V

1234

G

-V

+V

+V

-V

X

Intensity

Focus

TR

C C

1

2

./NORM.

Q

Reset

Set

X-Position

X-Y

DC,AC,GND

LEVEL

DC

C G

ND

GND

C

DC

Delay

Line

DelayON-OFF

. 5.4


7/36

. 5. 69

RC,

. ,

.

, ,

1 10pF.

, .

.

, (1cm). ,

.

Volts/div. , 5mv/div. (-

1:1) 20V/div. (4000:1). ,

15V/div.,

15V30005mV

YG = = (5.3)

. 5.4 . -

, ,

. Volts CAL.,

. -

,

Y. Volts CAL.

, 5

, . -

position, . , .

,

(dc ), C

(ac ). C, 100nF/500V, -

. ac -

, ,

. ac

, C-

(1/C). , ac ,

duty cycle. ,

duty cycley. (GND),

, o ,

.

, position.

-

.

. 20z

100 z . -

. -

20z 10z,


8/36

70

10z, -

. ,

10z -

. 30MHz,

.

. 95% ,

20MHz, 2MHz. ,

20z , 3dB,

0.707.

, . -

10% 90% (. 5.5). ,

10% 90%

, 0.8cm 7.2cm.

0.35[s]

[Hz]osct

BW (5.4)

,

. , . 5.5,

Volts CAL. ,

2.5cm . , 10% 90%

2cm .

10%

5cm

100%

trm

90%

0

. 5.5


9/36

. 5. 71

trm

tr, tosc, -

2 2

rm r osc

t t t= + (5.5)

tosc 20z, . (5.4), 17.5ns.

, trm30ns,

tr = 24.4ns (30 24.4) / 24.4 23%e= = . tosc 5rm osct t> .

5.3.2

f,

.

.

. , x,

.

Vsw1

Vsw2

Tsw

= 1ms

0.1ms/div.

5V/div.

f = 2kHz

usw

hold off

. 5.6


10/36

72

usw (. 5.6), -

( ),

.

(Vsw1) Vsw2. -

,

Vsw1 Vsw2 . Vsw2

Vsw1,

. .

(hold off period)

Vsw1. hold off ,

.

Tsw= 1ms,

10 1ms

0.1ms/div.

ime/div., RC (.

5.4). Tsw,

Time CAL.

0.1ms/div.

5 (. 5.6),

1/(5 0.1ms) = 2kHzf = . 3 . -, 5V/div,

15V.

5.3.3

, f

. -

. ,

,

.

, . 5.4,

flipflop, .

. 5.7. , . 5.7,

.

, (internal triggering), (external triggering). INT./EXT.

,

. (Line) -

.

-

, ucomp low high

flipflopusff high.

flipflophigh, .

uswVsw1,

, Vsw2,

.


11/36

. 5. 73

+

_

usff

usw

Vsw1

ucomp

Vsw2

Tsw

F.F.

Set

Q

Reset

ucomp

usff

usw

rprp

fp fp

Vsw1

. 5.7

Tsw-

(Time/div.). ,

Vsw1. flipflop,

low. flipfloplow -

Vsw1,

, .

.

flipflop

. (unblanking), ,

.

(. 5.4).

-

, (automatic triggering),

./NORM. ,

,

, .

(GND).

-

LEVEL, (normal triggering).

, . ,


12/36

74

,

.

,

. 5.7, (rising edge), rp.

, -

(falling edge), fp. SLOPE +/-

.

-

, Trigger selector .

. AC

. DC

. F ,

,

LF .

Line, -

, .

Line -

. , Line

thyristors,

.

Trigger selector

-

. TV trigger, . 5.4,

video.

, ,

(delay line) , . -

,

. ,

.

,

(SLOPE +/-), ,

.

5.3.4

, .

. 5.4 . ,

, . ,

.

. (alternate

mode), (. 5.8).

1kHz,

(flickering). ,

flipflop .

usff .

(chopped mode), -, (. 5.8).

(chopper oscillator), MHz.


13/36

. 5. 75

H uch,

.

. ,

. -

, -

, . 5.8. ALT./CHOP.

,

flipflopchopper.

usw

1 2

()

()

usw

1

2

uch

. 5.8 () ()


14/36

76

(INVERT), . 5.4 -

1, 1 (

180).

, -

.

()

+

_

F.F.

Set Q

Reset

Time/div.

Time/div.

usw_m

usw_d

Delay

Tsw_d

Tsw_m

td

()

Tsw_d

Tsw_m

usw_m

usw_d

td

. 5.9

().().


15/36

. 5. 77

,

,

.

, usw_d (. 5.9).

Tsw_d,

Tsw_m usw_m. td, , .

(.

5.9).

, . ,

x, .

, X

Y. ,

1 2, u1(u2).

X-Y

,

Lissajous. XY

X,

. 20z,

X2MHz (3dB),

X-Y, 100kHz.

5.3.5

. 5.4 ,

(), (G) (A1, A2, A3, A4).

6.3Vac, 1900V . HAMEG 2035.

1900V 1878V,

(). usff.

Intensity ,

.

1930V.

2, (focus)

. 2 1575V.

1 3 , 4 -

+72V. 1 3,

87V, . .

-

. ,

,

.

, -

.

. ,

TR,

(trace rotation).. 5.4

20MHz, 2kV. , -


16/36

78

, -

. ,

, -

15kV 20kV, 100MHz.

5.4

-

(probes). -

.

,

1M 10pF. -

,

BNC(. 5.10). -

(passive probes) :

1:1 (1X). 10:1 (10X).

100:1 (100X) 1000:1 (1000X).

,

1:1 10:1 (1X/10X). .

1:1

20V/div. 160Vpp. H

1, 100pF/m,

, .

, (10k),

100kHz.

1X, -

1//100pF, 10X.

10:1 ,

RpCp, . 5.11.

(1)

(2)

(3)

(4)

(5)

(6)

(7)

. 5.10 1:1 10:1. BNC

(1), (2), (3),

(4), (5), (6)(7),


17/36

. 5. 79

u

uosc

()R

p

Cp

u uoscCcbl CoscRcbl Rosc

()

Rp

Cp

. 5.11 (probe) 10:1 ().

()

Rp 9, -

1 ,

10:1. H Cp

, . . 5.11-

10, , Rosc,

CoscRcbl, Ccbl

. u

, uosc

1

1 1

oscp

p p

R

j RCu u

RR

j RC j R C

+=

++ +

(5.6)

, //cbl oscR R R= cbl oscC C C= + . . (5.6) -. ,

p pR C RC= (5.7)

. (5.6)

osc

p

Ru u

R R=

+ (5.8)


18/36

80

() () ()

. 5.12 10:1, .

()(), Cp()

. (5.7) Cp

10:1,

.

, . 5.12. . 5.12, Cp.

10X, -

, .

10//16pF. , -

,

.

10(5Hz).

. -

, 50Hz,

10M, 50MHz 1.5k.

,

1X. -

(Volts/div.).

400V, dc . ,

,

.

1001000, 100 1000 .

3pF. 50. 50

(1pF) -

, .

-

(active probes), , FET. -

,

,

. ,

0.42pF,

( 4GHz).

100k10. , ,


19/36

. 5. 81

.

.

10V,

10volt.

(differential

probes). (. 5.13), (floating) .

,

.

, .

.

(current probes). (. 5.13)

, ,

. AC,

AC/DC

. AC ,

2GHz. , AC/DC ,

Hall,

DC

100MHz. (split)

(solid).

.

.

() ()

. 5.13 (), : (1),

(2),

BNC (3) (4).

() , 100A (500A peak)

DC10MHz (1), 500A (700A peak) DC2MHz (2), 20A (50A peak) DC17MHz (3).Tektronix


20/36

82

5.5 LISSAJOUS

,

.

, . . 5.14,

2V/div. 0.5ms/div.,

13 2 6VV = =

22 2 4VV = =

, 1/ 1/(8 0.5ms) 250Hzf T= = = .

o o o3360 360 1358

t

T = = = (5.9)

,

, Lissajous.

LissajousXY . XY,y

x.

siny yu V t= (5.10)

sin( )x xu V t = (5.11)

, y xV V=

, Lissajous. 5.15. 0180

, 90270, Lissajous.

V1

V2

t

T

2V/div.

0.5ms/div.

. 5.14 ,


21/36

. 5. 83

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

10180

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

() () ()

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

() () ()

. 5.15 Lissajous

. : () 0180

, () 30

330

, () 60

300

,

() 90270

, () 120

240

, () 150

210

a b-

yx(. 5.16),

1 1sin siny x

y x

b b

a a = = (5.12)

ay

ax

by

bx

. 5.16

Lissajous


22/36

84

. (5.12), -

(y x

V V ). , . (5.12) -

o o0 90 . ,

= o360 = . , . 5.15,

, o180 = ., siny y yu V t= , -

, sinx x xu V t = . Lissajous ,

/y x

. , ,

, . 5.17. uy

uxf, Lissajous

1/f.

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

() ()

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

-1 -0.5 0 0.5 1

-1

-0.5

0

0.5

1

() ()

. 5.17 Lissajous

sin(3 )yu t= , : ()o

sin( 15 )xu t= ,() osin( 30 )xu t= , ()

osin(2 0 )xu t= , ()osin(2 20 )xu t=


23/36

. 5. 85

y, ux

Lissajous.

.

uy. ,

xu . , . 5.17, , uy

, ux ,

y x. , . 5.17,

/ 3 / 2y x = .

5.6 (DSO)

, .

. , ,

-

.

, . -

.

,

(). ,

.

, -

. , . ,

, .

(digital storage oscilloscopes, DSO),

-

.

DSO ,

-

, .

,

(A/D converters).

DSO A/D,

. (resolution)

bits ,

A/D.

. ,

.

, DSO-

.

DSO . -

, , DSO:


24/36

86

, , ,

, , .

, -

(autoranging).

, , ,

, , DSO , FFT.

.

, -

. DSO-

RS232C GPIB (488). DSO

DOS format.

,

.

, -

, DSO-

, 50GHz.

, .

.

,

. , ,

, . ,

.

DSO, , -

, -. -

, . , DSO

, . ,

DSO. , -

(LCD).

5.6.1 DSO

, -

, -

. , . -

,

. . 5.18 DSO-

,

. ,

.

, .

3dB, 70.7%

.

Volts/div. -

, A/D.


25/36

. 5. 87

Y

X

1234G

GDP

D/A

A/D-1

-11

A/D-2

-22

-

interface

:

Volts/div., Time/div. ..

R/W

R/Wtrig.

sampling

sampling

Volts/div.

Volts/div.

1

2

GPIB, RS-232C

Address

Bus

Data

Bus

X

Y

1

2

. 5.18 (DSO)


26/36

88

A/D, -

DSO -

. A/D:

. -A/D, 05V, 010V, 5V +5V

10V +10V. , , .

.

, -.

, bits ().,

. DSO,

, A/D

(successive approximation A/D converters) (flash A/D converters).

, -

.

, 21 ,

.

Nbits.

-

,

.

,

sample and hold.

,

. DSO . 5.18 , . -

.

A/D

1GHz, 1ns.

A/D , DSO

CCD (Charge Coupled Device).

CCD , A/D

.

, CCD.

A/D

, . -

DSO. . 5.18

.

DSO. -

(digitizer) .

,

. ,

DSO,

DSO .

(graphics display processor, GDP), (D/A converter).


27/36

. 5. 89

.

,

. -

(pixels) ,

. , 28= 256

29 = 512 , 217 = 131072 .

, bits

A/D. A/D 8bits, 28 = 256

, DSO

256 . 512 , -

512 . -

,

.

bits .

pixels , bit

, D/A.

256 byte

D/A8bits.

(GDP) ,

D/A

. -

.

. , -

. -

., DSO-

, . , -

, , -

. ,

, .

DSO, -

,

. interface . 5.18.

DSO,

DSO

. , DSO ,

.

,

,

. -

, -

. -

DSO. , -

,

.


28/36

90

5.6.2

DSO

. ,

.

, -. , DSO

-

, . -

,

.

x(t)

. (. 5.19)

Fourier X(f), . 5.19,

fx. , -

, ( ), (.

5.19)

( ) ( )sk

s t t kT

=

= (5.13)

, Ts, . -

Fourier(. 5.19)

( ) ( )s s

k

S f f f kf

=

= (5.14)

-

. 5.20 . fs= 1/Ts,

. ,

xs(t) (. 5.19)

( ) ( ) ( )sx t x t s t= (5.15)

Fourierxs(t)

( ) ( )s s sk

X f f X f kf

=

= (5.16)

. 5.19

x(t) fs.

fs-

fx, x(t) ,

xs(t), (. 5.20).

fc, ,

x c s xf f f f (5.17)


29/36

. 5. 91

()

t

t

t

s(t)

x(t)

xs(t)

()

() ()

() ()

()

f

f

f

f

Ts 2Ts 3Ts 4Ts

0-Ts-4Ts

X(f )

S(f )

Xs(f )

Afs

A

fs

0-fs

fs1

fs

-fs

0

0

0 fx

-fx

fx fc

-fx-fc

-fs

fsfs - fx fs + fx

LPF

Xs(f )

fs

>2fx

fs

2fx(), fs< 2fx()

xs(t). ,

, X(f).

, x(t) fx-

2s xf f , x(t)

xs(t) . (5.17).

2s xf f= Nyquist. Nyquist,

x(t), . 5.19. , x(t) xs(t)

, (aliasing). ,

fx 2s xf f< ,

(aliased sine wave) s x

f f .

s(t)

, s . (.

5.21), xs(t)


30/36

92

s(t)

x(t)x

s(t)

fc-fc 0

1( )sf x t

(LPF)

. 5.20 x(t)

1

( ) ( ) ( ) ( ) 2 cos(2 )s o k sk

x t x t s t x t C C kf t

=

= = +

(5.18)

Fourier

( ) ( )s k sk

X f C X f kf

== (5.19)

, /o sC T= 0 sin( ) /s s sk kC f kf kf =

. (5.19) . (5.16) , -

Ck-

. fs.

,

.

fc

-fc 0

(LPF)x(t) xs(t)

s(t)

()

t

x(t)

f

X(f )

0 fx

-fx

0 fx

-fx

s(t)

xs(t)

()

Xs(f )

()

ff

c-f

c-fs fsf

s- f

xf

s+ f

x

LPF

-2fs

2fs

fs

>2fx

st

Ts/

x(t)Ts/

. 5.21 x(t), s(t) ,

fs(). () ()


31/36

. 5. 93

1/ /o sC T = , x(t).

-

, Nyquist, -

fx, . -

fx

40dB .

5.6.3

DSO-

N bits A/D. ,

,

.

,

(interpolation) . - ,

. DSO

sin(x)/x.

fx, -

4.2s xf f= . , . , DSO10 ,

42, 512

.

sin(x)/x .

, DSO

. 5.22, .

,

fx (. 5.22).

sin(x)/x

, . sin(x)/x

,

fx. sin(x)/x

.

DSO -

. , ,

.

, DSO250MHz, 1GHz. ,

.

, . -

, fs

,

10sf =

(5.20)

, 10 .. (5.20) , -

.


32/36

94

-1. 5

-1

-0. 5

0

0. 5

1

1. 5

()

-1.5

-1

-0.5

0

0.5

1

1.5

()

. 5.22 fx,

fs= 4.2fx() fs= 13fx(),

. 1GHz

50s/div., 500000 . -

, fs. 512 ,

fs= 1GHz 50ns/div.

DSO-

,

. ,

.

, -

(500000), (512).

, ,

scrolling-

.

DSO ,

, . ,

fs, ,

N1. ,

/ 2x sf f> . 1MHzsf = ( 0.01)MHzx sf kf= + 1, 2, 3k=


33/36

. 5. 95

10kHz, -

. ,

,

.

5.6.4

DSO-

.

(real time sampling single shot sampling). -

.

fs,

fx, .

Nyquist 2s xf f , -.

, . ,

A/D,

(. 5.23).

(. 5.18),

. DSO

. ,

,

, .

, -

, fx.

, (equivalent time sampling).

Nyquist,

DSO.

,

(sequential sampling) (random

repetitive sampling).

(. 5.23). tk \k=1, 2, 3

tst, ( 1 0k k st st t t t t kt = + = + ). , .

.

tst,

,

.

. 5.23 ,

. -

, 10GHz, ,

. ,

DSO. -

, , -

(pretrigger view), .


34/36

96

()

t

t0

()

0.0

()

t1=t

0+t

st

t2=t

1+t

stt3=t

2+t

stt4 t

5 t6

t7

t8

12 3 4

5

6

7

8

910

1112 13

14

15

tk

tst

t5

tk-1

0.0

0.0

t

t

t1 t

3

1

2

3

3

2

1

3

2

1

1

11

2

2

2

3

3

3

t2

. 5.23 (), ()

(). , . ,

DSO


35/36

. 5. 97

t

0.0

. 5.24 ,

8.

,

,

, .

, . 5.23. ,

, .

,

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.

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-

.

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D/A

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36/36

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.

(VCO),

, .

PLL, ,

,

. D/A 8bits,

256 . D/A

,

DSO.

Electrical Measurements 05 Oscilloscopes

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Transcript of Electrical Measurements 05 Oscilloscopes