Universum FT-81015, Service Manual

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12
100Hz FEATURE BOX
VPC3215, CIP3250, SDA9400, DDP3310
The feature box consists of four I2C controlled ICs:
Video Processor VPC3215
Component Interface Processor CIP3250
Digital Image Processor SDA9400
Digital Deflection Processor DDP3310
The input supplies to the feature box are +12V, +5V. The ICs do also need a supply of 3.3V, which is regulated
by IC4 LM314.
Besides the composite video in normal operation and luma/chroma inputs in the SVHS applications, there are also R-G-
B-FB inputs from the PIP module.
OSD R-G-B-FB inputs from the Megatext IC or from the controller in the case of TV-text option. While the 50Hz sync
signals for PIP are supplied by the VPC3215, the 100Hz sync signals for OSD are supplied by the DDP3310.
Control signals for HV stage such as VertQ, Vert, HDrive, EW (East-West) and SVM (Scan Velocity Modulation) are
produced by this module. VProt and HProt input signals are used for protection. There are also a flyback sample signal
from HV stage and the sense signal from the CRT board.
The feature box also supports the VGA mode.
VPC32X5 (Video Processor)
Figure 1
As seen in figure 1 all the processings in VPC are digital. This IC has four composite, one SVHS input, and one composite
output which is used for teletext. In AK28 the main video input is Vin2, which is also used for luma input in SVHS applications.
After switching the inputs the signals are converted to digital via two 8 bit ADCs. And these digital data are processed to
produce the 4:2:2 formatted digital YUV signals. The main features are, multi-standard color decoding including all sub-
standards, multi-standard sync processing, adaptive 4H comb filter, linear horizontal scaling, as well as nonlinear horizontal
scaling (panorama vision.) It provides 50Hz vertical and 15625Hz horizontal sync signals for the PIP module.
Features:
n all-digital video processing
n high-performance adaptive 4H comb filter Y/C separator with adjustable vertical peaking
n multi-standard color decoder PAL/NTSC/SECAM including all substandards
n 4 composite, 1 S-VHS input, 1 composite output
n integrated high-quality A/D converters and associated clamp and AGC circuits
n multi-standard sync processing
n linear horizontal scaling (0.25 ... 4), as well as non-linear horizontal scaling ‘panorama vision’
n PAL+ preprocessing (VPC 3215)
n line-locked clock, data and sync output (VPC 3215)
n display/deflection control (VPC 3205)
n submicron CMOS technology
n I2C-Bus Interface
n one 20.25 MHz crystal, few external components
n 68-pin PLCC package