Test Circuits
(Continued)
DS012684-12
*
Note: All video inputs must have a series 33鈩?resistor for protection against EOS (Electrical Over Stress). If the OSD input signals are external to the monitor,
or these signals are present any time when +12V is not fully powered up, then the OSD inputs also require a series 33鈩?resistor.
FIGURE 7. LM1283 OSD Video Preamp Demonstration Board Schematic
Pin Descriptions
Pin No.
1
2
3
Pin Name
Red OSD Input
Green OSD Input
Blue OSD Input
Schematic
Description
These inputs accept standard TTL inputs. Each
color is either fully on (logic high) or fully off
(logic low). Connect unused pins to ground
with a 47k resistor.
4
Video/OSD Switch
This input accepts a standard TTL input.
H = OSD
L = Video
Connect to ground with a 47k resistor when
not using OSD.
9
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