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The
Analogue
supply stages arrive at the main board
as +15V3 and –15V3 rails these are filtered L1002 and
L1015 before being regulated by the adjustable
regulators at locations
REG1000
and
REG1002
to
p/- 12V rails for the Analogue output stage.
Regulator
REG1001
is fed from the +15V3 rail and
forms the Audio DAC supply.
The
Display board
requires several supply voltages
these are simply passed through the main board,
being filtered on the way to prevent transmission of
noise through to the surrounding electronics. The
display takes the +5V, -19V, -13V5 and -9V the –13V5
and –9V form a floating 4.5V supply biased relative to
the –19V grid voltage.
Display Board
The main component of the Display board is
IC1
this is
a Vacuum Florescent Display driver with keyboard san
and a serial data in/out interface.
The Chip receives display drive serial data from the
Vaddis V
chip on the main board via Con1 on pins 12,
13 and 14 these will be seen a
DIN
,
STS
and
CLK
this
data is used to drive the VFD a
DOUT
line interfaces
with the VADDIS V and supplies Keyboard Scan
information. The keyboard scan is a 6 x 4 matrix with
the
Key Source
appearing at S3, S4, S5, S6 and the
Keyscan
data returns appearing a K2, K3 and K4.
Please see:
above for
power supply
information.
The
Infra red
pick-up at location RXI receives RC5
data and send the data to the Vaddis V on the main
board via transistors TR2 and TR3, LED 2 is used to
mix the rear panel RC5, this is covered in-depth within
the Coms and Video output section of this guide.
Main Board electronics.
Zoran Vaddis V.
The main processor/control chip on the main board is the
Zoran Vaddis V at location
IC202
, this is the latest
incarnation of the very popular Vaddis range of processors
and allows for a much lower component count when
compared to our earlier players as many of the playback
functions have moved onto the Vaddis V silicon.
Below you will see the
major functions
of the Vaddis V
o
20 Bit digital video output for external Video
DAC’s and HDMI output stage.
o
Decoded Analogue Video output (internal
DAC) used on the DV78 only.
o
Digital Audio output 3 data lines 6 channels for
internal L + R DAC’s and L + R + C + LS + RS
for DV79 and DV29 also used for HDMI for the
DV79 and DV29.
o
SPDIF output.
o
Internal display interface.
o
Internal ATAPI interface.
o
Internal IR interface.
o
Serial in/out for RS232
A more detailed explanation of the Vaddis V and
peripheral components follows.
Vaddis Power
The Vaddis V is powered by two separate supplies the
Vaddis requires a 1.8v supply for the core, this is regulated
from the 3.3v rail by
REG1003
, the 3.3v rail is used to
supply power to the I/P – O/P ports of the chip.
ATAPI interface
CON203
is an ATAPI interface on a 40 way IDE
connector. This is decoupled from the Drive via an array of
decoupling resistors as required by the ATAPI spec.