June 1998
LM1282
110 MHz RGB Video Amplifier System with On Screen
Display (OSD)
n TTL OSD inputs, 50 MHz bandwidth
n On chip blanking, outputs under 0.1 V when blanked
n High speed Video/OSD switch
n Independent drive control for each channel for color
General Description
The LM1282 is a full feature video amplifier with OSD inputs,
all within a 28-pin package. This part is intended for use in
monitors with resolutions up to 1280 x 1024. The video sec-
tion of the LM1282 features three matched video amplifiers
with blanking. All of the video amplifier adjustments feature
balance
n 0V to 4V, high impedance DC contrast control with over
40 dB range
high input impedance 0V to 4V DC controls, providing easy
n 0V to 4V, high impedance DC drive control (0 dB to
−12 dB range)
n 0V to 4V, high impedance DC OSD contrast control with
over 40 dB range
n Capable of 7 VPP output swing (slight reduction in
bandwidth)
n Output stage directly drives most hybrid or discrete CRT
drivers
interfacing to bus controlled alignment systems. The OSD
section features three TTL inputs and a DC contrast control.
The switching between the OSD and video section is con-
trolled by a single TTL input. Although the OSD signals are
TTL inputs, these signals are internally processed to match
the OSD logic low level to the video black level. When ad-
justing the drive controls for color balance of the video sig-
nal, the color balance of the OSD display will track these
color adjustments. The LM1282 also features an internal
spot killer circuit to protect the CRT when the monitor is
turned off. For applications without OSD insertion please re-
fer to the LM1205 or LM1208 data sheets.
Applications
n High resolution RGB CRT monitors requiring OSD
capability
Features
@
n Three wideband video amplifiers 110 MHz −3 dB
(4 VPP output)
Block and Connection Diagram
DS012519-1
FIGURE 1. Order Number LM1282N
See NS Package Number N28B
© 1998 National Semiconductor Corporation
DS012519
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