Datasheet

V
IN
CSOUT
HSOUT
BPOUT
VSOUT
OEOUT
COLOR
BURST
START OF FIELD 1
ODD FIELD
LINE # 1 3 4 5 6 7 9 10 11525 2 8
3H
H
3H 3H
T
VSOUT
= 3H
H
½ H
VERTICAL SYNC
SERRATION
TP2
Odd/Even
Field Output
2
1
TP3
Burst/Back
Porch Output
2
1
TP4
Composite
Sync Output
2
1
TP5
Vertical Sync
Output
2
1
TP6
Horizontal
Sync Output
2
1
R
6
100:
R
7
100:
R
8
100:
R
4
100:
R
5
100:
7
6
8
9
10
OEOUT
BPOUT
CSOUT
VSOUT
HSOUT
LMH1980
4
5
3
2
1
R
EXT
GND
V
CC
V
IN
HD
U2
R
2
10 k:
1%
C
5
0.1 PF
C
3
0.1 PF
+
C
4
10 PF
R
3
10 k:
R
10
100:
TP1
HD Detect Flag Output
2
1
J2
GND
TP7
GND
1
1
J1
V
CC
TP8
V
CC
1
1
R
9
100:
C
2
560 pF
C
1
*OPT
Q1
MMBT3904
R
1
75:
BNC
J3
LMH1980
www.ti.com SNLS263A –JULY 2007–REVISED MARCH 2013
LMH1980 Test Circuit
Figure 2. Test Circuit
The LMH1980 test circuit is shown in Figure 2. The video generator should provide a clean, low-noise video input
signal with minimal sync pulse overshoot over 75Ω coaxial cable, which should be impedance-matched with a
75Ω load termination resistor to prevent unwanted signal distortion. The output waveforms should be monitored
using a low-capacitance probe on an oscilloscope with at least 500 MHz bandwidth. See PCB LAYOUT
CONSIDERATIONS for more information about signal and supply trace routing and component placement. Also,
refer to the “LMH1980 Evaluation Board Instruction Manual” Application Note (AN-1618 [SNLA096]).
SDTV Vertical Interval Timing Diagrams (NTSC, PAL, 480I, 576I)
Figure 3. NTSC Odd Field Vertical Interval
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