For Video Equipment
MN67621F
Color Video Camera Synchronizing Signal Generator LSI
Overview
The MN67621F generates color video camera synchro-
nizing signals for the NTSC, PAL, and SECAM video
systems.
It divides the reference frequency to generate the horizon-
tal synchronizing signal f
H
, the vertical synchronizing
signal f
V
, and the composite synchronizing signal.
A built-in 4f
SC
crystal oscillator circuit divides the fre-
quency by four to generate the color subcarrier frequency
signals SC1 and SC2.
Pin Assignment
Features
Supports CCDs with 420, 510, 590, and 670 H pixels
Supports NTSC, PAL, and SECAM video systems
PAL system 25Hz offset
Includes built-in oscillator circuit using external
crystal
Generates 14 signals, including the horizontal and
vertical synchronizing signals and the color
subcarrier frequency signals.
VD
N.C.
N.C.
N.C.
N.C.
PBLK
N.C.
N.C.
WBKL
(TOP VIEW)
QFP044-P-1010
Applications
Color video cameras
OSCI
1
2
3
4
5
6
7
8
9
10
11
TEST1
TEST2
TEST3
V
SS1
CLK
V
DD1
EO
N.C.
ED
N.C.
N.C.
34
35
36
37
38
39
40
41
42
43
44
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
N.C.
N.C.
N.C.
CCDS2
CCDS1
CSYNC
CBLK
CP2
TVMD2
SCBLK
FMTP
TVMD1
LSW
BFIDP
N.C.
WHD
V
SS2
SC2
SC1
V
DD2
N.C.
OSCO
MN67621F
Block Diagram
For Video Equipment
TEST1
TEST2
35
34
MIXER
36
TEST3
1/2
1/2
4f
SC
(P)
12
(N)
1/910
11
OSCO
OSCI
SC1
15
SC2
16
1/4
øD
40
EO
f
H
/f
V
17
37
(N)
(P)
V
SS2
V
SS1
LSW
1/2
21
42
18
V
DD2
V
DD1
H dec.
14
39
202f
H
/206f
H
26
23
9
C dec.
27
28
24
6
2f
H
20
V dec.
1/525
1/625
f
V
1
1/101 2f
H
1/103
f
H
HD
WHD
CP2
FMTP
WBLK
CBLK
CSYNC
SCBLK
PBLK
BFIDP
VD
CCDS1
29
38
1/3
1/8
1/5
1/7
22
CLK
TVMD1
TVMD2
25
1/2
CCDS2
30
For Video Equipment
Pin Descriptions
Pin No.
39
37
14
17
11
12
38
Symbol
V
DD1
V
SS1
V
DD2
V
SS2
OSCI
OSCO
CLK
Pin Name
Power supply
Power supply
Power supply
Power supply
Crystal oscillation
input
Crystal oscillation
input
Clock input
MN67621F
Function Description
"H" level (5 V) power supply for horizontal and vertical
synchronizing signal circuits
"L" level (0 V) power supply for horizontal and vertical
synchronizing signal circuits
"H" level (5 V) power supply for color subcarrier circuits
"L" level (0 V) power supply for color subcarrier circuits
Connect these pins to a 4f
SC
crystal oscillator.
The pins have built-in feedback resistors.
If using an external clock, supply it to the OSCI pin and
leave the OSCO pin open.
Supply the reference clock for the horizontal and vertical
synchronizing signals.
NTSC
PAL
"L"
"H"
510H
"H"
"L"
590H
"L"
"H"
SECAM
"L"
"L"
670H
"L"
"L"
22
25
29
30
34
35
36
15
16
TVMD1
TVMD2
CCDS1
CCDS2
TEST1
TEST2
TEST3
SC1
SC2
Television system
selection input
TVMD1
TVMD2
"H"
—
420H
The pins include built-in pull-up resistors.
CCD scan lines
selection input
CCDS1
CCDS2
"H"
"H"
The pins include built-in pull-up resistors.
Test input
f
SC
(B-Y) output
f
SC
(R-Y) output
Test inputs
Keep these pins at "L" level.
The pins include built-in pull-down resistors.
This color subcarrier signal is formed by dividing the
crystal oscillator frequency (4f
SC
) by four.
Color subcarrier signal
If SC1 is the 180° signal, this signal has the following phase.
NTSC system: 90°
PAL system:
90° when LSW is at "L" level
270° when LSW is at "H" level
28
1
18
27
42
26
CSYNC
VD
WHD
CBLK
HD
CP2
Composite synchronizing
signal output
Vertical drive output
Wide HD output
Composite blanking
output
Horizontal drive output
Clamp pulse output
Composite blanking signal
Vertical drive signal
Wide HD signal
Preblanking signal
Composite blanking signal
Signal for erasing video signal
Horizontal drive signal
Clamp pulses for luminance and color difference signals
Horizontal deflection start pulses
MN67621F
Pin Descriptions (continued)
Pin No.
9
Symbol
WBLK
Pin Name
Composite wide blanking
output
20
BFIDP
Output for burst flag/
identification signal
For Video Equipment
Function Description
Composite wide blanking signal
This pin produces blanking pulses wider than the CELK
pulses for both horizontal and vertical synchronization.
For NTSC and PAL systems, this is the burst flag (BF)
output, which gates the color subcarrier signal.
For the SECAM system, this is the identification (IDP)
signal, which switches the subcarrier waveform.
6
PBLK
Composite preblanking
output
Composite preblanking signal
This pin produces blanking pulses narrower than the CBLK
pulses for both horizontal and vertical synchronization.
Line switch signal
The chip generates this signal for each horizontal scan line.
During NTSC operation, this pin remains at "L" level.
This pin provides the FM demodulator trigger signal for the
SECAM system.
During NTSC operation, this pin remains at "L" level.
21
LSW
Line switch signal
output
23
FMTP
Trigger signal output
24
SCBLK
Subcarrier blanking
signal output
This pin provides the signal for erasing the subcarrier signal
for the SECAM system.
During NTSC operation, this pin remains at "L" level.
Phase comparator output
40
EO
Phase comparator
output
Operating Modes
(1) Television system
TVMD1
NTSC
PAL
SECAM
H
L
L
TVMD2
—
H
L
(2) CCD pixels and reference clock (CLK) frequencies
CCD
pixels
420H
510H
590H
670H
CCDS1
H
H
L
L
CCDS2
H
L
H
L
CLK frequency (MHz)
NTSC
15.891606
(1010f
H
)
9.534964
(606f
H
)
22.248249
(1414f
H
)
25.426570
(1616f
H
)
PAL/SECAM
16.09375
(1030f
H
)
9.65625
(618f
H
)
22.53125
(1442f
H
)
25.75000
(1648f
H
)
Frequency divider ratio
for first stage
1/5
1/3
1/7
1/8
For Video Equipment
H Decoder Pulse Timing Chart for NTSC
MN67621F
1H=63.55µs
0
H-SYNC
(*1)
CSYNC EO
–4.72
V-SER
5.35
BF
–1.57
CBLK
HD
8.50
WHD
2.20
CP2
7.24
PBLK
–9.12
WBLK
9.44
7.87
4.72
Unit: µs
17.52
*1
420 H
510 H
590 H
670 H
:
:
:
:
2.33
2.31
2.34
2.36
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