Part # LM2457 datasheet

Part Manufacturer: National Semiconductor

National Semiconductor

Part Description: LM2457 Monolithic Triple 7.5nS CRT Driver With Integrated Clamp and G1 Blanking


Part Details:

LM2457 October 2000 Monolithic LM2457Monolithic Triple 7.5nS CRT Driver With IntegratedClamp and G1 Blanking General Description The output of the G1 driver can also be used to drive a T voltage boost capacitor (22uF). When connected between riple The LM2457 driver is an integrated high voltage triple CRT the G1 drive output and the 120v supply input pin, a 120v driver circuit designed for use in color monitor applications. boost supply is achieved which can be used to drive the The input signal interface to the IC is a multiplexed signal internal DC clamp circuit, thereby eliminating the require- containing both clamp and video signal information, relative 7.5nS ment for a 120V clamp supply. to an external 1.7 VDC reference. The IC is packaged in an industry standard 15 lead TO-220 The IC contains three high gain, differential input, high input molded plastic power package. impedance, wide band amplifiers which directly drive theRGB cathodes of a CRT. Each channel has its gain internally Features CRT set to -52 and can drive CRT capacitive loads as well asresistive loads present in other applications, limited only by n 7.5ns low power driver the package s power dissipation. n Three integrated active clamp circuits Driver Integrated with the driver is a triple video clamp circuit for DC n Integrated 120V supply and G1 vertical blank drive recovery of each of the AC coupled video outputs. The DC circuit clamp circuit amplifies the clamp signal that is multiplexed on n Multiplexed signal interface to LM125X OSD Pre-amp the video signal input. The DC clamp amplifiers are high minimizes pin count while increasing functionality gain, differential input, high input impedance amplifiers, set- n External System voltage reference W ting a low impedance DC level at the clamp output which can n Convenient TO-220 staggered lead package ith be used to restore the DC level of the cathode drive. Eachchannel has a gain that is internally set to +75. Recommended Applications Integrated Also integrated within the package is a 43V vertical blank- p-p n 1024 x 768 Resolution displays up to 85Hz refresh ing driver that is designed to drive the vertical retrace blank-ing signal to the G1. This is a current limited, low impedance n Pixel clock frequencies up to 95MHz output capable of driving normal G1 decoupling capaci- n Monitor requiring horizontal video blanking


Please click the following link to download the datasheet:

LM2457.pdf Datasheet