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PHILIPS TECHNICAL TRAINING

L05HD TRAINING MANUAL




PHILIPS CONSUMER ELECTRONICS
64 PERIMETER CENTER EAST
PO BOX 467300
ATLANTA, GA 31146-7300

MM032205
TABLE OF CONTENTS

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

POWER SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

AUXILIARY POWER SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

MAIN POWER SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

DEFLECTION SYNC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

TV SIGNAL PROCESSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

DEFLECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

VIDEO SIGNAL FLOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

CRT DRIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18

AUDIO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

SIDE JACK PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

TROUBLESHOOTING TO PANEL LEVEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Introduction

The L05HD TV chassis is designed for the model year 2005. This set is High Definition ready
with an NTSC tuning system. To receive the ATSC channels a set top box is required.

This design is used in large screen sizes of 27 and 30 inch with the 27-inch having a 4:3
aspect ration and the 30 inch version having a 16:9 aspect ratio. There are three types of
CRTs used which are the 100 degrees, 110 degrees, and wide screen version.

The standard architecture consists of a Main panel (called the family board), a Picture Tube
panel, a Side I/O panel, a HDMI panel, a HD panel, and a Top Control panel. The panels
consists primarily of conventional components with some surface mounted devices.

The functions for 1fH video and audio processing is performed in one IC (TDA1200xx, IC
7200), the Hercules chip. This chip is located on the solder side of the main panel.

The functions for the HD signals and 1fH to 2fH conversion is performed on the HD panel.
Except for switching, OSD, Closed Caption, Text, and A/D conversion, the bulk of the pro-
cessing is performed by the Trident chip, IC 7201.

The L05HD chassis has two signal processing sections, one for the 1fH (NTSC), and one for
2fH (HD) processing. Whatever signal is applied to the set, it is displayed on the CRT in a
1080i format.

The NTSC tuning system features 181 channels with on-screen display. The main tuning
system uses a tuner, a microcomputer, and a memory IC mounted on the main panel. The
microcomputer communicates with the memory IC, Remote Receiver, Tuner, Signal process-
ing IC, and HD processing section. The Memory IC retains the settings for favorite stations,
customer-preferred settings, and circuit settings. The circuit settings can be accessed by the
service technician via the Service Alignment mode.

The On-screen graphics and Closed Caption decoding are done within IC 7206 located on
the HD panel. They are added to the main signal in the Display Processor, 7221, located on
the HD panel.

Customer Operation

The L05 customer menu is similar to the L04 customer menu. The L05HD does not have
Picture-in-Picture.

Press the Menu button to make a selection. Press the Cursor up-down buttons on the
remote to highlight the desired selection. Press the right Cursor button to make the selection.




Page1
Press the Menu button on the remote and press the Cursor up-down button to obtain the
following screens.




Page 2
Setting up the access code.

1. Press the Menu button on the remote Main Features
Timer
to display the on-screen menu. Picture
Sound
Timer
Rotation Rotation
Timer
Start Time
Features AutoLock AutoLock Stop Time
Install Active Control Active Control Channel
2. Press the Cursor up or down buttons Digi. Pic. Demo Digi. Pic. Demo Activate
Display
until the word features are highlighted.

3. Press the Cursor right button to display
the features menu options. Features Features
Timer Access Code T imer Access Code
Rotation ---- Rotation XXXX
4. Press the Cursor up or down buttons AutoLock
Active Control
AutoLock
Active Control
until the words autolock are highlighted. Digi. Pic. Demo Digi. Pic. Demo



5. Press the Cursor right button. The
screen will read, "Access Code ----"
Features Features
T imer Access Code T imer New Code
6. Using the number buttons, enter 0, 7, Rotation XXXX Rotation ----
1, 1. XXXX will appear as you press AutoLock
Active Control
Incorrect AutoLock
Active Control
the buttons. Digi. Pic. Demo Digi. Pic. Demo




Incorrect code will appear on the screen.
Enter 0711 again.
Features AutoLock
T imer Confirm Code Block Channel
7. The screen will ask you to enter a new Rotation XXXX Setup Code Of fStop T ime
code. Enter any 4 digit code. AutoLock
Active Control
Clear All
Block All
Channel
Activate
Digi. Pic. Demo Movie Rating Display
TV Rating




1 2
4

2 VOL
3
4 5
6
7


Page 3
Power Supply Block (Figure 1)

The Power supplies are both located on the Family board. The supplies are divided into two
sections, the Auxiliary and Main section. A single filter and rectifier circuit supplies both
sections. The Auxiliary supply operates in a low power mode when the load is reduced. In
the standby mode, the 3.3 and 6 volt supplies are operating. The 3.3 volt supply provides
power to the processor section of the Hercules. The 6 volt supply provides power to the IR
receiver. The Main supply is switched Off via the Standby line.

When the set is turned On, the "B" line from the Hercules processor goes High switching
7547 which turns 7535, 7509, and 7545 On. The +3V3A, +6VA, +12VA, and +8VA supplies
are then switched On. The load placed on the Aux Power supply will cause it to switch to the
full power mode. At the same time, the STBY line switches Low turning the Main SMPS
supply On. The supply produces a +6 volt, +140 volt, -16 volt, and +16 volt supplies.

The +Vaudio (+16 volt) supply switches on the degauss relay.




Page 4 FIGURE 1 - POWER SUPPLY BLOCK
Auxiliary Power Supply (Figure 2)

IC 7510 is the heart of the Auxiliary Power supply. In the Standby mode, VIA the current
sensing and Control circuits, a low power condition is detected by the IC. The IC then goes
into a Burst Mode operation to reduce the power used by the circuit. In the Burst Mode, the
supply will operate at approximately 25 kHz. In full power operation the frequency will be
approximately 66 kHz.

When power is first applied to the set, Start up is supplied to the IC by the internal Start-Up
current through Pin 14. Startup voltage is also applied to the IC to Pin 2 by the AC_IN line
which is tied to the neutral side of the AC line. During normal operation, power is supplied to
the IC by the HOT windings, Pins 1 and 2, of transformer 5504. Output drive from Pin 11 is
applied to the Gate of Transistor 7525. Voltage developed across the current sensing resis-
tors in the Source of 7525 provides current sense information to the IC. When 7525 is
switched Off, the voltage on Pin 1 of 5504 goes High. This winding supplies the operating
voltage the power supply circuit. It also turns Transistor 7567 On causing the Gate of 7525 to
stay Low as long as Pin 1 of 5504 is High. This prevents 7525 from turning On until the field
of 5504 has collapsed.

Regulation is accomplished by monitoring the +3 volt supply. This voltage is fed to Shunt
regulator 7542 which controls the current through opto-isolator 7516. Shunt Regulator 7542
begins conducting when Pin 3 of the IC reaches 2.5 volts. At this point current flows through
the opto-isolator, 7516. The transistor inside 7516 turns On applying a control voltage to Pin
6 of 7510. If a problem should develop in the feedback circuit causing an excessive voltage
on Pin 6, Transistor 7549-2 will turn On, switching Transistor 7532 On. This will a voltage to
the Demag circuit on Pin 7 causing the IC to latch Off. The IC will stay latched until power is
removed and reapplied to the set.

In the Standby mode, the "B" control line from the Hercules Processor is Low. Only the +3,
+3V3, and +6 volt supplies are present. When the set is turned On, the "B" line will go High,
turning Transistors 7509, 7545, and 7535 On. This will switch On the +8VA, +12VA, +8V,
+3V3A, +6VA, and +5V supplies.

In normal operation, voltage from Pin 12 of 5504 is rectified by 6540 to produce a negative
voltage which prevents Transistor 7561 from turning On. If AC is removed from the set, this
negative voltage will disappear. The voltage across the filter capacitors on the +3V line will
turn 7561 On. The Power Down line will then go Low signaling the processor to shut the set
down.




Page 5
Page 6




To 1533 Of
AUXILIARY POWER SUPPLY VDC 1534
+3V3A
1533
1
2
+3V3A
+8V

1 Source Select + 3 Vaux_GND1
Vaux_GND
2 Microcontroller 4 9509
3 5 Vaux_GND




T 1000mA
4 6
Vaux_GND1




3535
1532
5 9554




4R7
2586 7
I565 Vaux_GND MAINSUPPLYGND
6 8 4567
VCC Vaux_GND
330p 21 On 7 9
I557 8 10
6532 11.8 Off +5V
2585


2582

100n



11 * 9536
1u0




+6VA




2592
* 12 9523




68p
BAV21WS F534 I534




2580


3592


2544
4551 POWER_DOWN




33K
E




10n




2n2
* 7585 Vaux_GND1 Vaux_GND1
3V2
0V BC857B C A4
I560 3551 I510 2524
I538 3563 6540 I588 6542 F577 6543




4585
1n0 B B 7561
4R7
BZX384-C18



* 4V5 0V PDTC143ZT To 1405
6533 I563 3525 I595 220R BAS316 BZX384-C12 BAS316
I528
6512


2526

100n




2510




2564

100n
C Of




22u
3V7 2539 3565 * Vaux_GND E
RGP10D 300K 3560 +8VA




3589
AC_IN 9534




10K
15K *




BAS316
* * 470p Vaux_GND1




470K
3588


6534




3567


3534
Deflection




3K3
I553 3599 6550 I558 6539 5524 7535 33R
I556 5523 I564 F578 +12VA
SI2307DS Controller
1M5 SARS03
* SB340L-7010 0086 10u F582
1535
4523 HEATSINK 1




470u 16V
15.5 On
BAS316
2528

470n
3528


6531




3598




2536




2534




9530
330K




5504 2
4M7




1m0
7510 3536 I568
11.5 Off TEA1507 6 7 * 3
FIGURE 2 - AUXILIARY POWER SUPPLY




7543
E L78L33ACZ
2 START-UP 14 2K2 5 Vaux_GND1
Vcc
SUPPLY
Drain 8
15V9 158V B Vaux_GND1 Vaux_GND +8V




3546
CURRENT SOURCE 1 3




68K
MANAGEMENT I599 5521 IN OUT Vaux_GND1
0V1 I536 4 2