LM2469TA/NOPB

Overview

The LM2469TA/NOPB is a monolithic triple high-gain CRT driver circuit designed for color monitor applications. It integrates three high input impedance wideband amplifiers that directly drive RGB cathodes with an internal gain of -20. The device operates within a supply voltage range of +60V to +85V and supports bias voltages from +8V to +15V. It features a typical rise time of 9.5ns and fall time of 10.5ns, maintaining stability with capacitive loads up to 20pF. Packaged in a standard 9-lead TO-220 molded plastic housing, it is suitable for resolutions up to 1024 x 768 at 70Hz.

Feature Summary

• Integrates three high input impedance wideband amplifiers for direct RGB cathode driving
• Maintains standard LM243X family pinout for simplified PCB layout
• Stable operation with capacitive loads up to 20pF and inductive peaking networks
• High gain configuration (-20) optimized for matching CMOS preamplifiers

Applications

• Color monitors supporting resolutions up to 1024 x 768 at 70Hz refresh rate
• Video systems utilizing pixel clock frequencies up to 75MHz
• Displays employing video blanking techniques

Procurement Notes

Verify the component origin carefully as National Semiconductor was acquired by Texas Instruments. Confirm the datasheet revision and specific ordering suffixes match your design requirements. Ensure thermal management solutions are adequate given the power dissipation characteristics under maximum operating conditions.

Selection Notes

Select this component for designs requiring high-speed video amplification with fixed gain. Ensure the application environment allows for proper heat sinking, as case temperature must remain below 100°C. Verify compatibility with existing LM126X preamplifiers if building complete video channels.

Part Context

The LM2469 belongs to the LM246X family of CRT drivers, serving as a replacement for discrete amplifier circuits. It is part of a broader ecosystem including LM126X preamplifiers and LM2479/2480 bias clamps for comprehensive video signal processing in legacy monitor architectures.

Replacement Considerations

LM2468TA/NOPB

FAQ

What is the recommended arc protection method for the LM2469 outputs?

Use fast transient response clamp diodes (such as FDH400) connected from CRT cathodes to ground and VCC, along with series resistors and high self-resonant frequency inductors to limit voltage stress during arcover events.

How does load capacitance affect the LM2469 performance?

Increased load capacitance primarily increases the rise time by approximately 1.8% per pF, while the fall time remains relatively constant.