Video In
Video In
Video In
Video In
Audio In
Audio In
Audio In
Audio In
I2S
I2S
Baseband
Audio Out Amp Speaker
BT.656
ch4ch3ch2ch1ch4ch3ch2ch1
Cb0 FF Cr6 Y11 Y0 00 Y6 Cr12
4-Channel D1 Time Division Multiplexed
Techwell
Techwell
Target ApplicationsTarget Applications
FeaturesFeatures
The TW2864 is Techwell’s 4th generation 4-in-1 video decoder and audio
codec for security surveillance applications. The device includes four high
quality NTSC/PAL video decoders that convert analog composite video
signal to digital component YCbCr data. The TW2864 contains four 10-bit
ADCs and proprietary clamp and gain controllers and utilizes adaptive 4H
comb filter for separating luminance & chrominance to reduce cross noise
artifacts. The TW2864 adopts the image enhancement techniques such as
IF compensation filter, CTI and programmable peaking. The TW2864 also
includes audio codec which has four audio ADCs and one audio DAC. A
built-in audio controller can generate digital outputs for recording/mixing
and accepts digital input for playback.
TW2864
Embedded DVR
Video Server
DVR PCI Card
4-Channel Video Decoder and Audio Codec
For Security Applications
Improved adaptive 4H comb filters for all
NTSC/PAL standards
Supports ITU-R BT.656 format or time
multiplexed output with 54MHz or 108MHz
Provides simultaneous 4-channel Full D1 or CIF
time-multiplexed outputs
PCM 8/16-bit and u-Law/A-Law 8-bit for audio
word length
Programmable audio sample rates: 8, 16, 32,
44.1 and 48kHz
Video Decoder
Accepts all NTSC(M/N/4.43) /
PAL(B/D/G/H/I/K/L/M/N/60) standards with auto
detection
Integrated four video analog anti-alias filters
and 10 bit CMOS ADCs
IF compensation filter for improvement of color
demodulation
Color Transient Improvement (CTI)
Automatic white peak control
Programmable hue, saturation, contrast,
brightness and sharpness
Proprietary fast video locking system for
non-realtime application
Field lock mode
Audio Codec
Integrated four audio ADCs and one audio DAC
Provides multi-channel audio mixed analog
output
Supports a standard I2S interface for record
output and playback input
Other Features
Audio and video sync function
Supports a two-wire serial host interface
Ultra low power consumption (Typical 500mW)
100 pin TQFP package
ch1
ch2
ch3
ch4
TW2864
MUX/
CODEC
108MHz Digital Video Output Mode
Typical Application Diagram
Techwell
90
NASDAQ:TWLL
TW2864
4-Channel Video Decoder and Audio Codec
For Security Applications
2007 Techwell Inc. All rights reserved.
TW2864 Block Diagram
