True international support for
NTSC, PAL and SECAM output
HDTV output capability
Adaptive flicker filtering
Supports resolutions from 320 x 200
to 1024 x 768
Software forward compatible
with the CX25870 and CX25871
Programmable overscan ratios
from 0% to 25%
Pin compatible with CX25872 and CX25873
64-pin TQFP
d i g i t a l i n f o t a i n m e n t p r o d u c t s
High Performance
Video Encoder with
HDTV Output
C X 2 5 8 7 4 / C X 2 5 8 7 5
Distinguishing Features
Highest-Quality Video Encoder with
"Adaptive" Flicker Filtering and HDTV Output
Conexant's CX25874 and CX25875 video encoders are specifically
designed to meet TV-out cost and performance requirements for
next-generation desktop and notebook PCs, game consoles and
set-top boxes. With software forward compatibility to the CX25870
and CX25871, manufacturers can quickly bring to market new solutions
that provide adaptive flicker filtering, ATSC High-Definition Television
(HDTV) output, and true international television display (NTSC, PAL
and SECAM output). The CX25874 and CX25875 support resolutions
from 320 x 200 to 1024 x 768 and programmable overscan ratios from
0% to 25%. The CX25874 and CX25875 also provide 48 automatic
configuration modes and offer 10-bit DACs.
HDTV Output
HDTV is here. More than 1 million consumers have purchased
HDTV sets. With the start of this television set transition, TV-out
capability must now include the ability to connect PCs, set-top
boxes, DVD players and game consoles to HDTV television sets.
The CX25874 and CX25875 can convert either YCrCb or RGB input
to HDTV output. While the CX25874 and CX25875 are in HDTV output
mode, the device will provide either analog RGB or analog YP
B
P
R
signals and automatically insert tri-level synchronization pulses
(when necessary) and vertical synchronizing "broad pulses".
The CX25874 and CX25875 are compliant with all existing HDTV
standards including EIA770-4, SMPTE 274M/293M/296M and support
all ATSC HDTV resolutions including 480p, 720p and 1080i.
d i g i t a l i n f o t a i n m e n t p r o d u c t s
High Performance
Video Encoder with
HDTV Output
C X 2 5 8 7 4 / C X 2 5 8 7 5
Adaptive Flicker Filtering
The CX25874 and CX25875 include Conexant's unique
adaptive flicker-filtering capability. With this feature, the
optimal amount of flicker filtering for a given application
is automatically determined by the characteristics of the
pixel content. Now both an Excel spreadsheet and DVD
movie can look great at the same time. Consumers
do not have to manually adjust the amount of flicker
filtering as they switch from applications requiring
significant flicker filtering (e.g., text-intensive applications
like an Excel spreadsheet) to those requiring little or no
flicker filtering (e.g., a DVD movie).
International Support
The CX25874 and CX25875 provide the most complete
support for products with TV-out functionality shipped
to the U.S. and international markets. The CX25874
and CX25875 support SCART and Wide Screen
Signaling (WSS) 16:9 aspect ratio. The international
standards supported include NTSC (North America,
Taiwan, Japan), PAL-B, D, G, H, I (Europe, Asia), PAL-M
(Brazil), PAL-N (Paraguay), PAL-Nc (Argentina), PAL-60,
ECAM-D, K, K1 (Russia), SECAM-B, G, H (Middle East)
and SECAM-L (France).
Pixel Input Formats and Timing
The CX25874 and CX25875 convert a wide range
of input formats to television video formats. The input
resolution can be non-interlaced with an active
resolution of 320 x 200 to 1024 x 768 or interlaced
such as CCIR601, CCIR656 and VESA VIP. Conexant
is the only provider of video encoders that have the
flexibility to offer any resolution in this range with
so many input and output format options. This includes
the exact resolution to display DVD movies in either
NTSC or PAL formats.
P[11:0]
HSYNC
VSYNC
BLANK
FIELD
SIC
SID
ALTADDR
RESET
SLEEP
XTALIN
XTALOUT
Input
Demux
Timing
Serial
Interface
XTAL
OSC
XTL_BFO
Color Space
Conversion
#1
Flicker
Filter/Scaler
FIFO
Internal
Reference
Video
Encoder
to internal clocks
PLL
DAC
Mux
Clock
Generation
10-bit
10-bit
10-bit
Bias
Gen
FSADJUST
COMP
VREF
DACA
DACB
DACC
10-bit
DACD
VBIAS
CLK 0
CLK 1
Color Space
Conversion
#2
CX25874/CX25875 block diagram
Automatic Configuration Modes
The CX25874 and CX25875 offer enhanced automatic
configuration mode functionality. A total of 48 different
modes are now available which provide pre-programmed
register settings for more than 95% of typical TV-out
settings. For example, PAL-M can be automatically
configured to an input resolution of 640 x 480 RGB with
a moderate amount of overscan compensation with just
a single register write.
CGMS Support
The CX25874 and CX25875 support the complete CGMS
set of standards. This includes 480i, 480p/525p, 720p/750p
and 1080i/1125i.
Overscan Compensation
The CX25874 and CX25875 support overscan ratios as
low as 0% (truly to the bezel of the TV) and as high as
25% (25% of the screen will be black).
Macrovision
TM
Support
The CX25875 provides Macrovision 7.1.L1 copy protection
and Macrovision 525/625p specification compliance.
f e a t u r e s a n d s p e c i f i c a t i o n s
www.conexant.com
General Information:
U.S. and Canada: (800) 854-8099
International: (949) 483-6996
Headquarters Newport Beach
4311 Jamboree Rd, P.O. Box C
Newport Beach, CA 92660-3095
Order# 101812A
01-0916
2001, Conexant Systems, Inc. All Rights Reserved.
Conexant and the Conexant logo are trademarks
of Conexant Systems, Inc. Other trademarks are
owned by their respective owners. Although Conexant
strives for accuracy in all its publications, this material
may contain errors or omissions and is subject to
change without notice.
THIS MATERIAL IS PROVIDED AS IS
AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE AND NON-INFRINGEMENT.
Conexant shall not be
liable for any special, indirect, incidental or consequential
damages as a result of its use.
HDTV output
CGMS support
Adaptive flicker filtering for enhanced
image and text sharpness
5-line vertical and horizontal
flicker filtering
Supports any input resolution from
320 x 200 to 1024 x 768
48 automatic configuration modes
Programmable power management
Software-forward compatibility with
the CX25870 and CX25871
Pin compatibility with the CX25872
and CX25873
SCART
WSS 16:9 (wide screen signaling)
support
Macrovision 7.1.L1 copy protection
(CX25875 only)
525p/625p specification compliance
(CX25875 only)
10-bit DACs for superior picture quality
Overscan compensation ratios
from 0 to 25%
Serial programming interface
Buffered crystal clock output
NTSC/PAL/SECAM TV outputs:
Interlaced or non-interlaced
Composite
S-video (Y/C)
Simultaneous S-video and
Composite
YUV
YCrCb non-interlaced input to
interlaced output
16-bit 4:2:2 multiplexed 8-bit input
24-bit 4:4:4 multiplexed 12-bit input
RGB non-interlaced input to
interlaced output
15/16-bit multiplexed 8-bit input
24-bit multiplexed 12-bit input
RGB non-interlaced input to RGB
non-interlaced output
15/16-bit multiplexed 8-bit input
24-bit multiplexed 12-bit input
RGB or YCrCb interlaced input to
interlaced output
CCIR656
CCIR601/DVD
VESA VIP
64-pin TQFP
Applications
Desktop PCs
Graphics cards
Notebook computers
Game consoles
Digital television receiver cards
Living room PCs
Internet PCs
Progressive DVD players
Set-top boxes
Product Features
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