Sony HCD-GTR888 Service Manual ▷ View online
5
There are 2 type of Switching regulator.
One is the same PWM control type as conventional of GTR333 .
And the other is Frequency control type of GTR555/777/888 which is
One is the same PWM control type as conventional of GTR333 .
And the other is Frequency control type of GTR555/777/888 which is
newly-used .
Following are descriptions of the Frequency control type.
Following are descriptions of the Frequency control type.
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(1) Input the AC power.
(2) The power-supply voltage passes through the rectifier.
(3) The power-supply voltage will be applied to the sub-transformer.
(4) The sub-transformer outputs 7.5V when Standby - mode.
(5) When it is in DEMO-mode, the SUB ON (H) will be applied from the
(2) The power-supply voltage passes through the rectifier.
(3) The power-supply voltage will be applied to the sub-transformer.
(4) The sub-transformer outputs 7.5V when Standby - mode.
(5) When it is in DEMO-mode, the SUB ON (H) will be applied from the
SYSTEM CONTROLLER(IC500).
(6) The SUB ON (H) is synchronized with input and supplies 13.5V.
(7) Also the power-supply voltage will be applied to the main-
(7) Also the power-supply voltage will be applied to the main-
transformer.
(8) When it is in Standby -mode and DEMO- mode, the main-
transformer supplies 0V.
When it is in Power on- mode, the MAIN ON(H) will be applied
from SYSTEM CONTROLLER.
(9) The MAIN ON(H) is synchronized with input and supplies DC104V to
DAMP BOARD.
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< Judgmental standard of the Switching regulator >
Due to switch over to Standby -mode, Demo-mode, Power on-mode,
the Input of SUB ON and MAIN ON switches
Due to switch over to Standby -mode, Demo-mode, Power on-mode,
the Input of SUB ON and MAIN ON switches
to H ,then confirm whether
the power output is
within the voltage limit of the Judgmental standard .
When the
Judgmental standard is out of the voltage limit ,replace the
whole Switching regulator.
<
Note
>
This Switching regulator is purchased by module,
when replace the part in Service or Business establishment,
the vender and designer cannot guarantee reliability .
Therefore, the repair with the part replacement including fuse
replacement do not perform.
when replace the part in Service or Business establishment,
the vender and designer cannot guarantee reliability .
Therefore, the repair with the part replacement including fuse
replacement do not perform.
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(1)AC input
(2)Fuse
(3)Rectifier
(4) Sub Power transformer
(5) CN3 Connector
pin1:7.5V-13.5V , pin3:GND , pin4: AC DET , pin5: MAIN ON,
pin6: SUB ON
(6) DC/DC Converter for Main Converter (=> DC400V)
(7) Switching regulator controller
(8) MAIN Power transformer
(9) CN2 Connecter
(2)Fuse
(3)Rectifier
(4) Sub Power transformer
(5) CN3 Connector
pin1:7.5V-13.5V , pin3:GND , pin4: AC DET , pin5: MAIN ON,
pin6: SUB ON
(6) DC/DC Converter for Main Converter (=> DC400V)
(7) Switching regulator controller
(8) MAIN Power transformer
(9) CN2 Connecter
pin4-6
: GND,
pin
1-3:
P
VDD(DC77V for GTR333)
(DC85V for GTR555/GTR777)
(DC104V for GTR888)
(DC104V for GTR888)
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