LM1238AAC/NA National Semiconductor, LM1238AAC/NA Datasheet - Page 6

• Manufacturer Part Number: LM1238AAC/NA
• Description: 110 MHz I2C Compatible RGB Preamplifier with Internal Simple OSD Generator and 4 DACs
• Manufacturer: National Semiconductor

www.national.com
Typical Performance Characteristics
SYSTEM INTERFACE SIGNALS
The Horizontal and Vertical Blanking and the Clamping input
signals are important for proper functionality of the LM1238.
Both blanking inputs must be present for OSD synchroniza-
tion. In addition, the Horizontal blanking input also assists in
setting the proper cathode black level, along with the Clamp-
ing pulse. The Vertical blanking input initiates a blanking
level at the LM1238 outputs which is programmable from 3
to 127 lines (we recommend at least 10). This can be op-
tionally disabled so there is no vertical blanking.
V
CC
= 5V, T
FIGURE 2. Logic Horizontal Blanking
FIGURE 3. Logic Vertical Blanking
A
= 25˚C unless otherwise specified
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FIGURE 4. Deflection Horizonal Blanking
FIGURE 5. Deflection Vertical Blanking
FIGURE 6. Logic Clamp Pulse
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