Philips 47PFL5403 Service Manual page 98

EN 98 9. LC8.2A LA
9.2 LCD Power Supply
The Power Supply Unit (PSU) in this chassis is a buy-in and is
a black-box for Service. When defective, a new panel must be
ordered and the defective panel must be returned for repair,
unless the main fuse of the unit is broken. Always replace the
fuse with one with the correct specifications! This part is
commonly available in the regular market.
Different PSUs are used in this chassis:
• 42" sets use an "LG" PSU (LGIT PLHL-T721A or -T720A)
• 47" sets use an "LG" PSU (LGIT PLHL-T722A)
• 52" sets use a "Delta" PSU (DPS-411AP A).
The 42" and 47" Power Supply Units deliver the high voltage to
drive the backlight units (no inverters needed). In addition, all
Power Supply Units deliver the following voltages to the
chassis:
• +3V3 to SSB
STBY
• +12 V to SSB
display
• +12 V and -12 V
audio
• +12 V to DC-DC converters to SSB
• +12 V to Bolt-on Supply (where applicable) to SSB
• +24 V to Bolt-on Supply (where applicable) to SSB.
9.3 DC/DC converters
On-board DC-DC converters convert the +12 V coming from
the PSU and deliver the following voltages:
• +5 V (+5V )
tuner
Circuit Descriptions, Abbreviation List, and IC Data Sheets
Figure 9-3 SSB bottom view
to SSB
audio
FLASH
MEMORY
AUDIO
PROCESSING
• +VTUN
• +5 V (+5V_SW)
• +3.3 V (+3V3_SW)
• +2.5 V (+2V5_SW)
• +1.8 V (+1V8_SW)
• +1.2 V (+1V2_SW)
• +8 V (+8V)
The following diagram shows the power supply architecture of
the SSB:
DC - DC CONVERSION
I_17760_059.eps
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