LM1281N National Semiconductor, LM1281N Datasheet - Page 10

• Manufacturer Part Number: LM1281N
• Description: IC VIDEO AMP SYSTEM 28-DIP
• Manufacturer: National Semiconductor

Specifications of LM1281N

• Applications: General Purpose
• Number Of Circuits: 3
• -3db Bandwidth: 85MHz
• Current - Supply: 95mA
• Current - Output / Channel: 28mA
• Voltage - Supply, Single/dual (±): 11.4 V ~ 12.6 V
• Mounting Type: Through Hole
• Package / Case: 28-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *LM1281N

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Pin No.
Pin Descriptions
11
10
21
12
13
14
26
27
28
15
16
17
19
24
1
2
3
4
5
8
6
9
7
Red OSD Input
Green OSD Input
Blue OSD Input
Video/OSD Switch
Red Video In
Green Video In
Blue Video In
V
Ground
V
Video Contrast
OSD Constrast
Blue Drive
Green Drive
Red Drive
Clamp Gate
Blank Gate
Blue Clamp Cap
Green Clamp Cap
Red Clamp Cap
CC1
REF
Pin Name
Schematic
10
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.
This input accepts a standard TTL input.
Connect to ground with a 47k resistor when
not using OSD.
Video inputs. These inputs must be AC
Coupled with a minimum of a 1 µF cap, 10 µF
is preferred. DC restoration is done at these
inputs. A series resistor of about 33
also be used.
Power supply pins (excluding output stage)
Ground pins. All grounds are internally
connected and must also be connected on the
PCB.
Pin used for additional filter capacitor to
internal reference. The voltage at this pin is
2.0V.
Contrast control pins:
Drive control pins:
Both pins accept TTL inputs and are active
low. The clamp gate provides DC restoration of
the video signal. The blank gate forces the
video outputs to below 200 mV.
The external clamp cap is charged and
discharged to the correction voltage needed for
DC restoration. 0.1 µF is the recommended
value.
H = OSD
L = Video
4V — no attenuation
0V — over 60 dB attenuation
4V — no attenuation
0V — 12 dB attenuation
Description
should