～
220V 50HZ
Rectification
Filtering
Left/right channel
power amplifying
level
C , SL, SR channel
power amplifying
level
～
16.3V
～
38V
Panel display
～
26 V
Filament voltage
Rectification
Filtering
～
2.2V
N101
PT6311
VFD
Display
Button control
MCU
Remote control receiving
Panel indicator light control area
DDA
DCK
DST
Figure 3.2.3.1 Control panel circuit block diagram
VFD101 is vacuum flourescent display screen and the most distinct feature is high brightness. The
working principle is similar with that of kinescope of TV set. Pin 1, 2, 46, 47 are filament power supply,
MCU controls SEG electrode through the control of PT6311 (N101) to make characters of corresponding
working state display on screen.
Remote control receiving circuit is mainly composed of remote control receiver HS0038A2 (N102),
in whicj pin 1 is grounded, pin 2 power supply end, pin 3 is signal receiving output pin and sent to MCU
directly to control corresponding circuit.
3.2.4 Power board
The function of power board is to provide all kinds of working voltage required by each unit circuit.
Shown as in the figure 3.2.4.1 AV321T (RU) adopts large-power round transformer. Centre and surround
channel of AV321T (RU) adopt CD1875 and 2
TDA2052 respectively, TDA2052 is mono channel power
amplifying and adopts separate positive/negative power supply.
×
Figure 3.2.4.1 Power block diagram
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Summary of Contents for AV311T
Page 1: ...service manual AV311T...
