FEATURES
23• YPBPR to RGBHV Conversion
• YPBPR Path: 70 MHz, −3 dB, 700 mVPP
Bandwidth
• RGB Path: 400 MHz, −3 dB, 700 mVPP
Bandwidth
• Supports PC Video Display Resolutions up to
UXGA (1600 x 1200 @ 75 Hz)
• Supports 480i, 480p, 576i, 576p, 720p, 1080i,
and 1080p
• Smart Video Format Detection for SD and HD
• Power Save Mode

APPLICATIONS
• TFT LCD Monitor
• CRT Monitor
• Set-Top Box
• Display Projector

DESCRIPTION
The LMH1251 is a wideband 2:1 analog video switch
with an integrated YPBPR to RGBHV converter. The
device accepts one set of YPBPR inputs and one set
of RGB/HSYNC/VSYNC inputs. Based on the input
selected, the output will be either a decoded TV or
buffered PC video signal.
The LMH1251 has a SYNC separator and processor
that is capable of extracting sync timing information
from both Standard Definition Television (SDTV) and
High Definition Television (HDTV) inputs. It provides
bi-level sync, and tri-level sync separation.
The color space conversion from YPBPR to RGB in
the LMH1251 is realized with a very high precision
fully analog dematrixer which provides superior chroma accuracy that is less than 2.5% of amplitude
and 1.5° of phase error on a vectorscope. It is
equipped with a smart video detection circuit which
automatically senses SDTV and HDTV video formats
and applies the appropriate color space conversion.
The LMH1251 is capable of handling SDTV, HDTV,
XGA, SXGA, and UXGA video formats, which makes
it an ideal solution for enhancing value in applications
ranging from LCD monitors, to set-top boxes, to
projectors. The LMH1251 is part of the LMH™ high
speed amplifier family, and is offered in a 24-pin
TSSOP package.