Convergence Video
Video Encoders/Decoders
Distinguishing Features
• Integrated NTSC/PAL/SECAM
video decoding
• Auto detection and configuration
for video
• Two 10 bit A/D
• YPbPr component video input
• Ease of Use
• 12mm X 12mm 80-pin TQFP
• 7mm X 7mm 64-pin TQFP
• CCIR 656/601/VIP
• Integrated anti-alias filter
• On-chip voltage regulator
High Performance in a Small Package
Conexant’s broadband communications portfolio includes a comprehensive
suite of semiconductor solutions that enable the digital home and information
network. The CX25836/7 is Conexant’s fourth-generation video decoding
solution. It provides a highly integrated single-chip analog video capture
solution ideal for a wide range of digital video systems applications.
The CX25836/7 features, although applicable to a wide range of analog video
applications, are focused on both the security and consumer electronics
markets. Most notably, CX25836’s fast camera locking capabilities and flexible
programmable inputs make it most suitable for the security camera market.
The CX25837, with its ability to decode Composite Video Baseband Signal
(CVBS), S-Video, and YPbPr, is best suited to address the wide array
of consumer electronics requirements. Both devices are distinguished by high
quality, flexibility, integration, and ease of use. Both fit into a wide array of
applications: set-top-boxes, flat panel displays (such as LCD and Plasma TVs),
HDTVs, and PVRs/DVRs.
High Quality
The CX25836/7 integrates two high-performance 10-bit ADCs and provides a
full 10-bit data path through the video decoder to maintain optimum end-to-
end video quality. Eight video inputs provide flexible analog muxing that can
be configured for any of the following:
• Eight CVBS inputs
• Four Y/C inputs
• Three composite with one Y/C and one YPbPr
• One composite with two Y/C and one YPbPr
• Two composite with two YPbPr (CX25837 only)
The CX25837 uses its high quality Analog-to-Digital Converter (ADC) to
sample the YPbPr video format, which is most often found on prosumer
(intermediate to advanced end user) type equipment. Simultaneous
digitization of Pb and Pr, through the 10-bit chrominance A/D, is used to
offer this feature cost effectively yet yield the highest quality.
Part Number CX25836/7
Description Single-Chip Video Decoder
Single-Chip Video Decoder
CX25836/7
Convergence Video
Video Encoders/Decoders
Integrated Filters
All video inputs have integrated anti-alias filters, eliminating the
need for external filter components. These filters help improve the
video decoding process by removing aliasing artifacts prior to the
digitization process.
Conexant also employs a proprietary method of luma/chroma
separation of the composite video sources. Conceptually similar
to a 4H adaptive chrominance comb filter used for NTSC and
PAL, Conexant performs a slight twist to provide unparalleled
performance. Through the use of adaptive correlation logic, the
resulting combed image provides improved performance over
a standard 4H comb solution. In the case where no correlation
exists between lines, the decoder automatically falls back to the
chrominance band-pass and luma notch filter.
In the case of SECAM, a bell filter is implemented. The net effect
of the various filtering stages results in a high-quality image with
reduced cross-chrominance and cross-luminance artifacts (such
as dot crawl, hanging dots, rainbow effects) and thus restores full
bandwidth to luminance data from composite sources.
CX25836/7 System Block Diagram
Flexible Architecture
With eight programmable input ports and a configurable output
port for 4:2:2 digital, the CX25836/7 can be used to capture
video from TV tuners, DVD players, video cameras, VCRs, game
consoles, or any other sources of composite Y/C or component
(480i) video. The CX25836/7 video inputs can be programmed
for up to eight video sources; a maximum of eight CVBS input
channels. Each of these inputs can be used to support CVBS,
S-Video, or component video inputs. The total number and
configuration of video inputs is user-defined.
Ease of Use
The CX25836/7 requires minimal programming for startup. These
devices are preconfigured in a default mode for development,
verification, and fast prototyping. Additionally, the CX25836/7 can
auto detect all worldwide broadcast video standards.
Internally, the CX25836/7 uses on-chip logic to determine
which video standard is present and reconfigures automatically
so no user intervention is necessary. This is especially useful
in geographic regions where different video standards may
be received on a channel-by-channel basis. However, like the
operation of traditional video decoders where the user chooses a
specific video standard, the automatic detection feature may be
turned off.
CVBS4/Y4/SIF1/Pb
CVBS1/Y1
XTI Master
Clock
Input
Audio Over -
Sample or
Generic Clock
Video
Decoder -
NTSC, PAL,
SECAM
with 4H
Adaptive
Comb
Filter
Video
Output
Port:
BT.656,
BT.601,
VIP 2.0
I/O Pin
MUX
2-Wire
Serial
Command
or
VIP Host
I/F
10-Bit
CVBS/
LUMA
ADC
10-Bit
Chroma/
Sound IF
ADC
Input MUX, Anti-alias Filter and AGC
XTO
CVBS2/Y2
CVBS3/Y3
CVBS5/C1/SIF2/Pb
CVBS6/C2/SIF3/Pb
CVBS7/C3/SIF4/Pr
SER_DATA/HAD[1]
CHIP_SEL/VIPCLK
HCTL/PRGM3
IRQ_N/PRGM4
PLL_CLK/PRGM7
SER_CLK/HAD[0]
PIXCLK
VID_DATA[7:0]
VRESET/PRGM3
HRESET/PRGM2
FIELD/PRGM1
DVALID/PRGM0
IR_RX/PRGM5
IR_TX/PRGM6
CVBS8/C4/SIF5/Pr
VBI Data Slicer and Decoder
Arbitrary
Horizontal
and Vertical
Multi-tap
Polyphase
Scaler
Moreover, the surrounding Bill of Materials (BOM) has been
integrated and optimized for performance and overall cost
effectiveness. Together, small package and integration yield
high performance in a small package. To maximize the customer’s
flexibility and minimize the board space by eliminating multiple
foot print options, the CX25837 is also offered in an 80-pin
12x12 mm device, which is pin-for-pin compatible with the
CX25840/1/2/3 broadcast A/V decoder. Broadcast audio can be
added by a
mere device change. Finally, the CX25836/7 has multiple
power-
down modes to address low-power applications and power
budget-sensitive designs. The video decoder is designed on
the latest sub-micron process, which reduces the overall power
consumption through the advantages of reduced geometries.
Part Ordering Numbers
Part
Number
6 Video
Input
Mux
8 Video
Input
Mux
Component
Video
Input
CX25836
X
VIP
Host
Port
X
CX25837
X
X
CX25837 Pinout (80-Pin)
64-Pin TQFP
7 x 7 x 1 mm Body Size
0.4 mm Pin Pitch
TEST
RESET_N
SLEEP
IR_TX/PRGM6
IR_RX/PRGM5
IRQ_N/PRGM4
VDDO
VSSO
VSS
VDD
SER_DATA/HAD[1]
SER_CLK/HAD[0]
CHIP_SEL/VIPCLK
VRESET/HCTL/PRGM3
VSS
VDD
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
HRESET/PRGM2
FILD/PRGM1
DVALID/PRGM0
VID_DATA[7]
VID_DATA[6]
VID_DATA[5]
VID_DATA[4]
VDDO
VSSO
VSS
VDD
VID_DATA[3]
VID_DATA[2]
VID_DATA[1]
VID_DATA[0]
PIXCLK
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
VAA_XTAL
XTO
XTI
VSS_XTAL
VSS_CH2
CVBS8/C4/SIF5/Pr2
VAA_CH2
CVBS7/C3/SIF4/Pr1
S2D_NEG2
CVBS6/C2/SIF3
IREF
CVBS5/C1/SIF2/Pb2
VSS_CH1
CVBS4/Y4/SIF1/Pb1
VAA_CH1
CVBS3/Y3
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
CVBS2/Y2
S2D_NEG1
CVBS1/Y1
ASUB
VAA_ADC1
VSS_ADC1
VSS_ADC2
VAA_ADC2
REG_OUT
REG_IN
VSS_PLL
VPP0
VPP1
VDDO_PLL
PLL_CLK/PRGM7
VSS0_PLL
80-Pin TQFP
12 x 12 x 1 mm Body Size
0.5 mm Pin Pitch
TEST
RESET_N
SLEEP
NC
NC
NC
NC
IR_TX/PRGM6
IR_RX/PRGM5
IRQ_N/PRGM4
VDDO
VSSO
VSS
VDD
SER_DATA/HAD[1]
SER_CLK/HAD[0]
CHIP_SEL/VIPCLK
VRESET/HCTL/PRGM3
VSS
VDD
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
HRESET/PRGM2
FIELD/PGRM1
DVALID/PRGM0
VID_DATA[7]
VID_DATA[6]
VID_DATA[5]
VID_DATA[4]
VDDO
VSSO
VSS
VDD
VID_DATA[3]
VID_DATA[2]
VID_DATA[1]
VID_DATA[0]
PIXCLK
NC
NC
NC
NC
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
NC
NC
NC
NC
VAA_XTAL
XTO
XTI
VSS_XTAL
VSS_CH2
CVBS8/C4SIF5/Pr2
VAA_CH2
CVBS8/C3/SIF4/Pr1
S2D_NEG2
CVBS6/C2/SIF3
IREF
CVBS5/C1/SIF2/Pb2
VSS_CH1
CVBS4/Y4/SIF1/Pb1
VAA_CH1
CVBS3/Y3
CVBS2/Y2
S2D_NEG1
CVBS1/Y1
ASUB
VAA_ADC1
VSS_ADC1
VSS_ADC2
VAA_ADC2
REG_OUT
REF_IN
VSS_PLL
VPP0
VPP1
VDDO_PLL
PLL_CLK/PRGM7
VSSO_PLL
NC
NC
NC
NC
CX25837 and CX25836 Pinout (64-Pin)
Superior Performance
The CX25836/7 high quality video decoder offers superior
performance through advances in technology, integration,
and patented intellectual property.
For example, a new and improved arbitrary horizontal and
vertical scaler, from full resolution down to an 8:1 ratio (icon
size), has been implemented using a polyphase interpolation
filter. This maintains a high-quality scaled image that preserves
the detail and aspect ratio of the source material. Scaling can be
accomplished in both ITU-R BT.656 and square formats.
Additionally, new advances in clamping, Automatic Gain Control
(AGC), and DC restore circuitry allow for faster lock times upon
channel change and improved signal reconstruction abilities to
improve the video decode process. The CX25836/7 is offered
in a compact 64-pin 7x7 mm TQFP and operates off of a single
3.3 V regulator.
© 2003, Conexant Systems, Inc. All Rights Reserved. Conexant and the Conexant
logo are registered trademarks of Conexant Systems, Inc. All 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.
Convergence Video
Video Encoders/Decoders
03-0887
CX25836/7 Features
• Auto detection and configuration
of NTSC/PAL/SECAM video
• Worldwide video standards – NTSC (M, J, 4.43), PAL
(B, D, G, H, I, M, N, Nc), SECAM (K, L)
• Full 10-Bit ADCs and data path
• Flexible video input mux with integrated
anti-alias filtering
• Four line adaptive comb filter for NTSC and PAL
• Flexible video output port - 27 MHz ITU-R BT.656,
VIP 2, or ITU-R BT.601 video with separate syncs
• Macrovision detection
• Programmable VBI data slicer for data services such
as closed caption, Teletext, and program guides
• Power-up configurable two wire serial command
interface or two wire VIP 1.1/2 host port interface
• Hardware interrupt to eliminate polling
• Auto detection and configuration for video
• Fast locking mode for security camera
applications (CX25836)
• Auxiliary clock output – For providing an oversampled
audio clock locked to the video or for use as a general
purpose PLL output
• Infrared transmit and receive logic
• Internal voltage regulation for single supply operation
• Lower power consumption
• Small form factor
• Pin for pin compatible devices
Video Decoder Applications
• Set-top-boxes
• Flat panel displays – LCD and Plasma TVs
• HDTVs
• PVRs/DVRs/VCRs
• TV tuners
• DVD players
• Video cameras
www.conexant.com
General Information:
U.S. and Canada: (888) 855-4562
International: (732) 345-7500
Headquarters
4000 MacArthur Blvd.
Newport Beach, CA 92660
Order# 102226A
Video Decoder
CX25836/7 MPEG CODEC
CVBS
L, R Stereo
Decoder
CCIR
656
CCIR
656
Audio
Clk
CamcorderTelevision
DVD Burner
Video
Encoder CVBS
CX25836/7 Diagram
