la7688b Sanyo Semiconductor Corporation, la7688b Datasheet - Page 11

• Manufacturer Part Number: la7688b
• Description: Pal/ntsc Color Television-use Single-chip Lsi
• Manufacturer: Sanyo Semiconductor Corporation

Continued from preceding page.
Description of LA7688B chroma block input waveforms
1. The color bar signals which are input from pin 10 and pin 14 are a standard composite video signal.
SIF signal level
[AUDIO SW block]
AF EXT gain
AF EXT distortion
(1) Color bar : 0dB
(2) Monochrome signal
(3) Burst only
(4) 8-division signal
Composite video signal with 1Vp-p color bar
[PAL] SYNC : 0.3Vp-p Burst : 300mVp-p Chroma : 600mVp-p
[NTSC] SYNC : 0.3Vp-p Burst : 286mVp-p Chroma : 572mVp-p
Signal obtained by eliminating the chroma component from the signal of (2)
Parameter
Sout
GAF
THDAF
Symbol
TPO-8
TPO-51
TPO-51
point
Test
SG1
fp = 38.9MHz
cw 80dBµ
SG2
fp = 33.4MHz
cw 60dBµ
SG1
fo = 400Hz
Vf = 500mVrms
SG1
fo = 400Hz
Vf = 500mVrms
symbol
Input
LA7688B
Mix SG1 and SG2 and enter the mixed
signal to VIF IN.
Connect the spectrum analyzer to
TPO-8 and measure the 5.5MHz level.
Apply the DC voltage so that I-1A
becomes EXT.
Enter SG1 from Z-12 and connect the
AC voltmeter to TPO-51.
Measure the 400Hz level and set it as
V51.
GAF = 20log V51/500mVrms
Apply the DC voltage so that I-1A
becomes EXT.
Enter SGI from Z-12 and connect a
distortion factor meter to TPO-51.
Measure the distortion factor in this
case.
B.P.F 20Hz to 20kHz
Test method
VR center
VR center
VR center
TPO-2
Applied voltage (V)
No.0077-11/20
TPZ-46
OPEN
7.8V
7.8V