Sony DXC-S500, Руководство по обслуживанию

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6-10
DXC-S500 (E)
Gigabit transceiver (IC114)
IC114 consists of a transmitter that encodes 16-bit parallel input data, converts the data into 20-bit serial
data, and outputs it as a differential signal with an amplitude of about 0.5 V and a receiver that decodes
20-bit differential serial input data and outputs it as 16-bit parallel data. In this unit, the transfer rate of
the differential serial data is 20 times the normal, that is, 900 Mbps (Mbits/sec) because 45 MHz (that is
the same as the clock input of TG) is used as a clock of parallel data (the transfer rate of video data is 22.5
MHz). By mutually connecting with the gigabit transceiver on the SY-301 board of CHU, a 10-bit video
signal, timing pulses (HD, VD, and ID), and serial communication data to a microcomputer are
transmitted in the route of CHU to CCU. A serial communication clock from a microcomputer, serial
data, chip select signals of each device, and an external trigger signal are received in the route of CCU to
CHU.
45 MHz clock and PLL circuit
A clock of 45 MHz generated in VCXO of X101 becomes a master clock of CHU and operates TG and a
gigabit transceiver. PLL is constituted by IC105 and IC106 for phase locking to prevent the beat
interference that occurs between a 45 MHz clock described above and a 45 MHz clock reproduced in the
reception part of the gigabit transceiver.
Serial A/D converter (IC111)
The serial A/D converter sends the analog voltage of a CCD temperature detection circuit to the
microcomputer of CCU as serial digital data.
12-channel D/A converter (IC112)
The 12-channel D/A converter receives the serial data sent from the microcomputer of CCU and outputs a
Peltier element’s power control signal, a draft/frame mode switching signal, and an SHP phase
adjustment voltage.
Serial EEPROM (IC113)
Serial EEPROM (IC113) memorizes the data peculiar to CHU. Immediately after the power is turned on,
the microcomputer of CCU reads data and initializes the unit. During line adjustment, the CCD
sensitivity, pre-white balance adjustment value, and CCD PPN position information are written as data.
Readjustment is not required even if the combination of CHU and CCU is changed by this system.
However, the unit must be readjusted when CCD of CHU is replaced or IC113 is replaced.