CWB308 / CWB309

CORPORATION

T = +25 C

A

o

f - Frequency (MHz)

TOTAL HARMONIC DISTORTION

-VS-

FREQUENCY

0.80

0.50

0.20

0.10

0.05

10

20

40

V-, V+ = _

V-, V+ = _

+15V Vanalog = 1.0Vrms

V-, V+ = _

+15V Vanalog = 0.3Vrms

+10V Vanalog = 1.0Vrms

DISTORTION -VS- FREQUENCY

POWER SUPPLY REJECTION RATIO POWER SUPPLY DECOUPLING CIRCUIT

IL

V+

LT

V-

S

D

IN

.22 F

µ

1K

Ω

1K

Ω

.22 F

µ

POWER SUPPLY REJECTION RATIO

-VS-

FREQUENCY

f - Frequency (MHz)

90

80

70

60

50

40

30

0.1

0.2

0.5

1.0

10.0

20

-PSRR

+PSRR

w/o Decoupling

-PSRR, +PSRR with Decoupling

MOD

V- = 15V, V+ = +15V

T = +25 C

A

o

V

= 4.0V -f-p

2.0

5.0

CWB309CP

50

D

S

Ω

C

V+

C

V-

LOGIC 1 = +5V

µ

C = 0.22 F // 10 F

50

Ω

µ

HP

SPECTRUM

ANALYSER

(or equivalent)

HARMONIC DISTORTION

10MHz - 40MHz

HP

GENERATOR

(or equivalent)

DISTORTION

-VS-

ANALOG INPUT VOLTAGE

10.0

1.0

0.3

0.1

0.05

0.02

0.3

1.0

3.0

5.0

Vanalog - Analog Input (Vrms)

Compensated

Total Harmonic

T = +25 C

A

o

V- = -15V, V+ = +15V

f = 10KHz, R = 50

L

Ω

5.0

2.0

By inserting 1K ohm resistors in series with V+ and V-

power supply lines and decoupling both pins at the device

socket, it is possible to improve power supply rejection

ratios of a video switch by 50dB at frequencies of 20MHz

and higher.