Circuit Description; Optical System (Ohb Block); Signal Processing/Transmission System - Sony Power HAD FX HSC300R Service Manual

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Circuit Description

1-3-1.

Optical System (OHB Block)

PA-418 Board
This board consists of a CCD drive H driver and a sample-hold IC, performs correlated double sampling for signals
from the CCD and outputs them differentially. The sample-hold IC adjusts sensitivity.
DR-675 Board
This board consists of a CCD, a buffer for CCD and sample-hold IC drive pulses and CCD V driver circuit.
TG-285 Board
This board consists of the following circuits.
• A PLD that generates CCD and sample-hold IC drive pulses and a video amplifier
• A circuit to lock and synchronize the INT PLL H signal generated by the PLD with the PLL H signals sent from
the DPR-358 board
The adjustment data and the defect correction data of the CCD block are stored in EEPROM (IC019).
1-3-2.

Signal Processing/Transmission System

DPR-358 Board
This board converts analog R/G/B signals that are input from the CCD block to digital signals, and camera process
processing and enhanced processing such as Knee and Gamma processing are performed for the digital signals in the
camera signal processor LSI (IC301).
Then the digital signals are down-converted to SD signals and signals for the viewfinder are generated by the subsequent
PLD (IC2002).
Output digital signals are sent to the SDI-117 board (HSC300RF/100RF) or the CD-78 board (HSC300R/100R) and are
then transmitted to the camera control unit.
The board contains the A/D converter for the analog return signal, the D/A converter for an analog video, and the
generator of the reference clock signal.
SDI-117 Board (HSC300RF/100RF)
The main-line video signal that multiplexes audio signal and command on the DPR-358 board is converted to a serial
optical signal by the parallel/serial converter and the electrical/optical converter. Then the converted serial optical signal
is sent to the camera control unit.
Furthermore, this board converts the serial optical signal that is sent from the camera control unit to a parallel electrical
signal.
Then the prompter video signal, audio signal and command that are multiplexed with the return video are separated
from each other, and each signal is sent to the DPR-358 board.
HSC300RF/HSC100RF/HSC300R/HSC100R
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