adv7188 Analog Devices, Inc., adv7188 Datasheet - Page 4

• Manufacturer Part Number: adv7188
• Description: Multiformat Sdtv Video Decoder With Fast Switch Overlay Support
• Manufacturer: Analog Devices, Inc.

ADV7188
INTRODUCTION
The ADV7188 is a high quality, single chip, multiformat video
decoder that automatically detects and converts PAL, NTSC,
and SECAM standards in the form of composite, S-video, and
component video into a digital ITU-R BT.656 format.
The advanced, highly flexible digital output interface enables
performance video decoding and conversion in line-locked, clock-
based systems. This makes the device ideally suited for a broad
range of applications with diverse analog video characteristics,
including tape-based sources, broadcast sources, security and
surveillance cameras, and professional systems.
ANALOG FRONT END
The ADV7188 analog front end includes four 12-bit NSV ADCs
that digitize the analog video signal before applying it to the
standard definition processor (SDP). The analog front end uses
differential channels for each ADC to ensure high performance
in mixed-signal applications.
The front end also includes a 12-channel input mux that enables
multiple video signals to be applied to the ADV7188. Current and
voltage clamps are positioned in front of each ADC to ensure
that the video signal remains within the range of the converter.
Fine clamping of the video signals is performed downstream
by digital fine clamping within the ADV7188. The ADCs are
configured to run in 4× oversampling mode.
The ADV7188 has optional antialiasing filters on each of
the four input channels. The filters are designed for standard
definition (SD) video with approximately 6 MHz bandwidth.
SCART and overlay functionality are enabled by the ability of
the ADV7188 to process CVBS and standard definition RGB
signals simultaneously. Signal mixing is controlled by the fast
blank (FB) pin.
AIN1–
AIN12
SCLK
ALSB
SDA
12
FB
INPUT
MUX
CONTROL AND VBI DATA
SYNC PROCESSING AND
CLOCK GENERATION
SERIAL INTERFACE
CLAMP
CLAMP
CLAMP
CLAMP
FILTER
FILTER
FILTER
FILTER
ALIAS
ALIAS
ALIAS
ALIAS
ANTI-
ANTI-
ANTI-
ANTI-
A/D
A/D
A/D
A/D
CLK CONTROL
12
12
12
12
SYNC AND
ADV7188
DECIMATION AND
PREPROCESSOR
DOWNSAMPLING
FILTERS
DATA
CONTROL
AND DATA
12
12
FUNCTIONAL BLOCK DIAGRAM
12
12
Cr
Cb
R
G
B
C
CVBS
COLOR SPACE
CONVERSION
VBI DATA RECOVERY
Rev. A | Page 4 of 112
MACROVISION
CVBS/Y
RECOVERY
DETECTION
CHROMA
DEMOD
Figure 1.
F
SC
STANDARD DEFINITION PROCESSOR (SDP)
The ADV7188 is capable of decoding a large selection of baseband
video signals in composite, S-video, and component formats. The
video standards that are supported include PAL B/D/I/G/H,
PAL 60, PAL M, PAL N, PAL Nc, NTSC M/J, NTSC 4.43, and
SECAM B/D/G/K/L. The ADV7188 can automatically detect
the video standard and process it accordingly.
The ADV7188 has a 5-line, superadaptive, 2D comb filter that
provides superior chrominance and luminance separation when
decoding a composite video signal. This highly adaptive filter
automatically adjusts its processing mode according to the video
standard and signal quality without requiring user intervention.
Video user controls such as brightness, contrast, saturation, and
hue are also available within the ADV7188.
The ADV7188 implements the patented ADLLT algorithm to
track varying video line lengths from sources such as a VCR.
ADLLT enables the ADV7188 to track and decode poor quality
video sources such as VCRs and noisy sources from tuner outputs,
VCD players, and camcorders. The ADV7188 contains a CTI
processor that sharpens the edge rate of chroma transitions,
resulting in sharper vertical transitions.
The ADV7188 can process a variety of VBI data services, such
as closed captioning (CC), wide-screen signaling (WSS), copy
generation management system (CGMS), Gemstar® 1×/2×,
extended data service (XDS), and teletext. The ADV7188 is
fully Macrovision certified; detection circuitry enables Type I,
Type II, and Type III protection levels to be identified and
reported to the user. The decoder is also fully robust to all
Macrovision signal inputs.
STANDARD DEFINITION PROCESSOR
EXTRACT
CHROMA
FILTER
FILTER
LUMA
SYNC
GLOBAL CONTROL
AUTODETECTION
STANDARD
RESAMPLE
RESAMPLE
RESAMPLE
CONTROL
CHROMA
LUMA
Y
Cr
Cb
OUTPUT CONTROL
2D COMB
2D COMB
(5H MAX)
CHROMA
(4H MAX)
LUMA
SYNTHESIZED
LLC CONTROL
FREE-RUN
Cr
Cb
Y
FAST BLANK
INSERTION
CONTROL
OVERLAY
AV CODE
AND
20
10
10
PIXEL
DATA
P19 TO P10
P9 TO P0
HS
VS
FIELD
LLC1
LLC2
SFL
INT