signal traces from the preamplifier to the LM2405 and from

the LM2405 to the CRT cathode should be as short as pos-

sible. The following references are recommended:

Ott, Henry W., “Noise Reduction Techniques in Electronic

Systems”, John Wiley and Sons, New York, 1976.

“Guide to CRT Video Design”, National Semiconductor Appli-

cation Note 861.

“Video Amplifier Design for Computer Monitors”, National

Semiconductor Application Note 1013.

Because of its high small signal bandwidth, the part may os-

cillate when it is used in a typical application with a preamp

in a monitor, if feedback occurs around the video amplifier

through the chassis wiring. To prevent this, leads to the input

circuit should be shielded, and input circuit wiring should be

spaced as far as possible from output circuit wiring. Power

should be removed as quickly as possible from an amplifier

that is oscillating, since power dissipation in the part is very

high in this mode and the part may be damaged if oscilla-

tions continue and the power supply can supply more than

250 mA.

TYPICAL APPLICATION

A typical application of the LM2405 is shown in

Figure 9.

Used in conjunction with an LM1205, a complete video chan-

nel from monitor input to CRT cathode can be achieved. Per-

formance is satisfactory for all applications up to 1280x1024

non-interlaced, and pixel clock frequencies up to 130 MHz.

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