XOCECO LC-42R27, Service Manual

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10
2. TVP5160
The TVP5160 device is a high quality; digital video decoder that digitizes and decodes all popular
baseband analog video formats into digital component video. The TVP5160 decoder supports the
A/D conversion of component YPbPr and RGB (SCART) signals, as well as the A/D conversion and
decoding of NTSC, PAL, and SECAM composite and S-Video into component YCbCr. Additionally,
component progressive signals can be digitized. The chip includes two 11-bit, 60-MSPS, A/D
converters (ADCs). Prior to each ADC, each analog channel contains an analog circuit, which
clamps the input to a reference voltage and applies a programmable gain and offset. A total of 12
video input terminals can be configured to a combination of YPbPr, RGB, CVBS,
and S-Video video inputs. Progressive component signals are sampled at 2x clock frequency (54
MHz) and are then decimated to the 1x rate. In SCART mode the component inputs and the CVBS
inputs are sampled at 54 MHz alternately, then decimated to the 1x rate. Composite or S-Video
signals are sampled at 4x the ITU-R BT.601 clock frequency (54 MHz), line-locked for correct pixel
alignment, and are then decimated to the 1x rate. CVBS decoding utilizes advanced 3D Y/C filtering
and 2-dimensional complementary 5-line adaptive comb filtering for both the luma and chroma data
paths to reduce both cross-luma and cross-chroma artifacts. 3D Y/C color separation may be used
on both PAL and NTSC video signals. A chroma trap filter is also available. On CVBS and Y/C
inputs, the user can control video characteristics such as hue, contrast, brightness, and saturation
via an I2C host port interface. Furthermore, luma peaking with programmable gain is included, as
well as a patented color transient improvement (CTI) circuit. Attenuation at higher frequencies or
asymmetrical color subcarrier sidebands are compensated using the IF compensation block. Frame
adaptive noise reduction may be applied to reduce temporal noise on CVBS, S-Video, or
component inputs. 3D noise reduction and 3D Y/C separation may be used at the same time or
independently. The TVP5160 decoder utilizes Texas Instruments’ patented technology for locking
to weak, noisy, or unstable signals and can auto-detect between broadcast quality and VCR-style
(nonstandard) video sources. The TVP5160 decoder generates synchronization, blanking, field,
active video window, horizontal and vertical syncs, clock, genlock (for downstream video encoder
synchronization), host CPU interrupt and programmable logic I/O signals, in addition to digital video
outputs. The TVP5160 decoder includes methods for advanced vertical blanking interval (VBI) data
retrieval. The VBI data processor (VDP) slices and performs error checking on teletext, closed
caption, and other VBI data. A built-in FIFO stores up to 11 lines of teletext data, and, with proper
host port synchronization, full-screen teletext retrieval is possible. The TVP5160 decoder can pass
through the output formatter 2x sampled raw Luma data for host-based VBI processing. Digital RGB
overlay can be synchronously switched with any video input, with all signals being oversampled at
4x the pixel rate.