Techwell
Mixed Signal Semiconductor Solutions
TECHWELL
VIDEO
DECODERS
NTSC/PAL/SECAM Video Decoder for Portable Applications
Features
Low Power NTSC/PAL/SECAM
Video Decoder with VBI Slicer
TW9900
Target Applications
Mobile Phone
Portable Media Player
Portable DVD player
Picture in Picture (PIP) decoder
DVD Recorder
The TW9900 is Techwell’s next generation low-cost multi-standard video
decoder chip that is designed for portable applications. It consumes less
than 100mW in typical composite input application. The available power
down mode further reduces the power consumption. It uses the 1.8V for
both analog and digital supply voltage and 3.3V for I/O power. A single
27MHz crystal is all that needed to decode all analog video standards.
The video decoder decodes the base-band analog CVBS or S-video signals
into digital 8-bit 4:2:2 YCbCr for output. It consists of analog front-end
with input source selection, variable gain ampli er and analog-to-digital
converters, Y/C separation circuit, multi-standard color decoder (PAL
BGHI, PAL M, PAL N, combination PAL N, NTSC M, NTSC 4.43 and SECAM)
and synchronization circuitry. The Y/C separation is done with high quality
adaptive 4H comb lter for reduced cross color and cross luminance. The
advanced synchronization processing circuitry can produce stable pictures
for non-standard signal as well as weak signal. The output of
the decoder is line-locked and formatted to the ITU-R 656 output with
embedded sync.
The TW9900 also includes circuits to detect and process vertical blanking
interval (VBI) signal. It slices and process VBI data for output through video
bus. Some information can also be alternatively retrieved through host
interface. It also detects copy-protected signal according to Macrovision
standard including AGC and colorstripe pulses.
A 2-wire serial host interface is used to simplify system integration. All the
functions can be controlled through this interface.
Video Decoder
NTSC (M, 4.43) and PAL (B, D, G, H, I, M, N, N
combination), PAL (60), SECAM support with
automatic format detection
Software selectable analog inputs allows any of
the following combinations, e.g. 2 CVBS or ( 1
CVBS and 1 Y/C ).
Built-in analog anti-aliasing lter
Two 10-bit ADCs and analog clamping circuit
Fully programmable static gain or automatic gain
control for the Y channel
Programmable white peak control for the Y
channel
Video Processing
4-H adaptive comb lter Y/C separation
PAL delay line for color phase error correction
Image enhancement with peaking and CTI
Digital sub-carrier PLL for accurate color
decoding
Digital Horizontal PLL for synchronization
processing and pixel sampling
Advanced synchronization processing and sync
detection for handling non-standard and weak
signal
Programmable hue, brightness, saturation,
contrast, and sharpness
Automatic color control and color killer
Chroma IF compensation
Detection o evel of copy protection according
to Macrovision standard
Application Diagram
NTSC/PAL
SECAM
Composite
S-Video
TV Tuner
TW9900
ITU-R 656
Techwell
Mixed Signal Semiconductor Solutions
www.techwellinc.com
NTSC/PAL/SECAM Video Decoder for Portable Applications
Low Power NTSC/PAL/SECAM Video Decoder with VBI Slicer
TW9900
TW9900 Block Diagram
Analog Video In
Chroma
Demodulation
CIN0
10-bit
ADC
VBI Slicer
U
Scaling / Video Interface
VD (7:0)
MUX0
4H Adaptive
Comb Filter
AGC
10-bit
ADC
MUX
V
Luma/Chroma
Processor
MUX1
HS
VS
CLKx2
Y
Clock
Sync
Processor
27Mhz
Line-lock
clock
Generator
MPOUT
PDN
SDAT
2 Wire
Serial Bus
SCLK
Miscellaneous
Two wire MPU serial bus interface
Support Real Time Control interface
Power save and Power down mode
Typical power consumption < 100mW
Single 27MHz crystal for all standards
Supports 24.54MHz and 29.5MHz crystal for high
resolution square pixel format decoding
3.3 V tolerant I/O
1.8V/3.3 V power supply
5x5mm² 32 TQFP package
Video Output
8-bit ITU-R 656 compatible YCbCr(4:2:2) output format
VBI slicer supporting industrial standard data services
VBI data pass through, raw ADC data output
LLC output support
About Techwell
Techwell is a fabless semiconductor company that designs, markets and sells mixed signal integrated circuits for multiple digital video
applications in the consumer, security surveillance and automotive markets, including advanced TVs, multifunction LCD monitors,DVD
Recorders, security surveillance systems and in-car LCD displays. Founded in 1997,we currently have over 160 employees and are
headquartered in San Jose,California, with additional R&D and sales activities in South Korea, Japan,Taiwan and China.
Techwell
For more information on Techwell, please contact us at 1-408-435-3888
© 2009 Techwell Inc. All rights reserved.
All other trademarks are property of their respective owners
Mixed Signal Semiconductor Solutions
TECHWELL INC.
TEL 1-408-435-3888 www.techwellinc.com
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
