LM1238
110 MHz I2C Compatible RGB Preamplifier with Internal
Simple OSD Generator and 4 DACs
General Description
The LM1238 pre-amp is an integrated, three channel video
pre-amp. It has an I2C compatible interface which allows
control of all the parameters necessary to directly setup and
adjust the gain and contrast in the CRT display. Four I2C
compatible DACs are available to control monitor bias and
brightness circuits. The LM1238 preamp is designed to be
100% compatible with the LM246x high gain driver family
and the LM2479/80 Clamp ICs.
Black level clamping of the video signal is carried out directly
on the AC coupled input signal into the high impedance
pre-amplifier inputs, eliminating the need for additional
clamp capacitors. Horizontal and vertical blanking of the
outputs is provided. Vertical blanking is optional and its
duration is register programmable.