Power Supply Board; Power Supply For Backlight System; Led Drive Board; 3D Ir Emitter Board - Sony KDL-32EX729 Service Training Manual

POWER SUPPLY BOARD

There are different Power Supply Boards used in the models in this
manual. The type of board depends on the size of LCD panel. They
are:
● G10 Board (32")
● G4B Board (40")
● G5 Board (46")
There are 3 distinct sections on the power supply:
Standby Supply: Continuously operational as long as AC power is
applied, the standby supply generates 3.3V for the circuits requiring
power while the unit is turned off. An unregulated 19V line is present
to provide power to the main relay, PFC and main power supply at
turn-on.
Main Supply: Once the power supply receives a power-on command
from the CPU on the Main Board, the main switching supply is turned
on to provide a regulated 12V source and an regulated 24V source
for the LED power supply circuits.
Converter: Generates the B+ for the local dimming (LED Drive
Board) circuits to control the backlighting level.

POWER SUPPLY FOR BACKLIGHT SYSTEM

Power for the LED backlights is provided for the LED Drive Board via
the G10 Board for the 32" models, G4B Board for the 40" models,
and the G5 Board for the 46" models.
KDL-32EX729/40EX729/46EX729
SECTION 3 - CHASSIS OVERVIEW

LED DRIVE BOARD

Designated as the LD Board the LED Drive Board is controlled by the
TCON/HFR Board to perform overall backlight power-on, backlight
level, and local dimming functions. The negative voltage rail is pulse
width modulated to control the on time of the LED backlights. LED
backlight brightness is controlled in 4 separate groups (quadrants).

3D IR EMITTER BOARD

Designated as the HEM2 Board, this board is the internal 3D IR
Emitter to synchronize the 3D shutter glasses..

SWITCH UNIT

This board contains the power, channel, and volume up/down and
menu buttons.

MOTION SENSOR BOARD

Designated as the HMS3 Board, the Motion Sensor Board contains
the circuits for the Motion Sensor. The Motion Sensor detects when
there is movement in front of the TV. If there is no movement in
front of the TV after a predetermine amount of time the backlight is
turned off (audio present). After an extended period of time the TV is
completely turned off.

IR BOARD

Designated as the HLR2 Board, the IR Board contains the power,
standby, and timer LED's are located on this board along with the IR
remote receiver and light level sensor.
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