Hitachi dp2x schematic
Dec 2004
(ver g)
Training Materials Prepared by: ALVIE RODGERS C.E.T.
MODEL RELEASE
HD READY PTV
Chassis Model # Aspect
DP-27 51SWX20B 16X9
57SWX20B
65SWX20B
DP-27D 57TWX20B 16X9
65TWX20B
DP-26 65XWX20B 16X9
57XWX20B
51XWX20B
DP-24 43FWX20B 16X9
DP-23G 57GWX20B 16X9
51GWX20B
DP-23K 46F500 16X9
DP-23 57UWX20B 16X9
57F500
57G500
51UWX20B
51F500
51G500
2002 and 2003
DIGITAL
CONTENTS... 2002 DP-2X Chassis Projection Television Information
INSTRUCTOR… Alvie Rodgers C.E.T. (Chamblee, GA.)
THIS PAGE LEFT BLANK
Dec 2004
(ver f)
TOPICS PAGE
SECTION (1) POWER SUPPLY DIAGRAMS:
•
+6V Lo Voltage Regulation
•
+6V Lo Voltage Regulation
•
+6V Lo Voltage Regulation
•
Power On Relay Controls
•
Power On Relay Controls
•
Power On Relay Controls
•
Power On Relay Controls
•
Low Voltage Shut Down
•
Low Voltage Shut Down
•
SW +115V Hi Voltage Regulation
•
SW +115V Hi Voltage Regulation
•
Additional
•
Additional
•
Protect (Deflection) Hi Volt Shut Down
•
Protect (Deflection) Hi Volt Shut Down
•
LEDs
•
LEDs
•
LEDs
•
LEDs
SECTION (2) MICROPROCESSOR INFORMATION:
•
Microprocessor
•
Microprocessor
•
Microprocessor
•
Microprocessor
•
Microprocessor
•
Microprocessor
•
Microprocessor
SECTION (3) VIDEO CIRCUIT INFORMATION:
•
Video NTSC
•
Video NTSC
•
Video NTSC
•
Video NTSC
•
Video Component, OSD & NTSC
•
Video Component, OSD & NTSC
•
Video Component, OSD & NTSC
•
Video Component, OSD & NTSC
•
ATSC (Digital Tuner)
Hi Voltage Shut Down
Hi Voltage Shut Down
(Visual Trouble Shooting) Lo Voltage Power Supply Circuit Diagram Explained ----
(Visual Trouble Shooting)
(Visual Trouble Shooting)
(Visual Trouble Shooting)
DP-2X TABLE OF CONTENTS
Circuit Diagram Explained ------------------------------------------
Circuit Diagram
Circuit Diagram
Circuit Diagram Explained ---------------------------------------------
Circuit Diagram
Circuit Diagram
Circuit Diagram
Circuit Diagram Explained ---------------------------------------------
Circuit Diagram -----------------------------------------------------------
Circuit Diagram Explained ----------------------------------
Circuit Diagram -----------------------------------------------
Circuit Diagram Explained -----------------------------------
Circuit Diagram ------------------------------------------------
Circuit Diagram DP-23, 23G and DP-24
Circuit Diagram DP-26
Circuit Diagram DP-27 and DP-27D
DATA COMMUNICATION
DATA COMMUNICATION
DATA COMMUNICATION
Sync Input
Sync Input
Sync Input
Sync Input
Circuit Diagram Explained
Circuit Diagram
Circuit Diagram
Circuit Diagram
Circuit Diagram Explained
Circuit Diagram
Circuit Diagram
Circuit Diagram
----------------------------------------------------------- 03-01
Circuit Diagram DP-23, 23G, 27 & 27D
Circuit Diagram DP-24
Circuit Diagram DP-26
Circuit Diagram Explanation --------------------------------
Circuit Diagram
Circuit Diagram
Circuit Diagram
Block Diagram
DP-26 Only
Materials prepared by
Alvie Rodgers C.E.T.
DP-26 and DP-27
DP-23, DP-23G and DP-24
DP-23, DP-23G and DP-24
DP-26
---------------------------------------------------
DP-27 and DP-27D
Circuit Diagram Explained ---------------------------
Circuit Diagram ----------------------------------------
------------------------------------------------
Explanation
Circuit Diagram DP-23, 23G, 24, 27 & 27D
Circuit Diagram DP-26
Circuit Diagram DP-23, 23G, 27 & 27D
Circuit Diagram DP-24
Circuit Diagram DP-26
------------------------------------------------ 03-04
------------------------------------------------ 03-05
DP-23, 23G, 27 & 27D
DP-24
DP-26
------------------------------------------------- 03-11
-------------------------------------
----------------------------
-------------------------------
-------------------------------------
-------------------------------
-----------------------------------
------------------------------------- 02-01
---------- 02-04
------------------------------ 02-05
----------------------------------------- 02-06
---------------- 02-07
-------------------------------- 02-08
-------------------------------- 02-09
-------------------------------- 03-03
------------------------
----------------------------------------
----------------------------------------
Continued on Next Page
01-01
01-02
01-03
01-04
01-06
01-07
01-08
01-09
01-13
01-14
01-15
01-16
01-17
01-18
01-19
01-20
01-21
01-22
01-23
03-06
03-08
03-09
03-10
Table of Contents Page 1 of 4
Dec 2003 (ver g)
SECTION (3) VIDEO CIRCUIT INFORMATION: (Continued)
•
•
•
•
•
•
•
•
•
SECTION (4) AUDIO CIRCUIT INFORMATION:
•
•
SECTION (5) DEFLECTION CIRCUIT:
•
•
•
•
•
•
•
•
•
SECTION (6) DIGITAL CONVERGENCE CIRCUIT INFORMATION:
•
•
•
•
•
•
•
•
•
•
•
SECTION (7) ADJUSTMENT INFORMATION:
•
•
•
•
TOPICS PAGE
Rainforest IC Pulse
Circuit Diagram Explanation
ABL
Circuit Diagram
ABL
ABL Switch
Audio Video Mute
Audio Video Mute
Input Circuit Diagram
DVI
Component Sync
Component Sync
Main Terminal Circuit Diagram Explanation
Audio
Main Terminal Circuit Diagram
Audio
Horizontal Drive
Horizontal Drive
IH01 Horizontal Drive IC
Sweep Loss
Sweep Loss
Vertical Output
Vertical Output
Pincushion Circuit
Pincushion Circuit
Digital Convergence Interconnect
Digital Convergence Interconnect
Digital Convergence Interconnect
Remote CLU4321UG
Remote CLU5721TSI
Remote CLU5722TSI
43" Overlay
46" Overlay
51" Overlay
57" Overlay
65" Overlay
Adjustment Order ------------------------------------------------------------------------------------ 07-01
Pre Heat Run ------------------------------------------------------------------------------------------ 07-02
Cut Off
Pre-Focus
Adjustment
DP-2X TABLE OF CONTENTS
Explanation Explained
------------------------------------------------------------------- 03-13
---------------------------------------------------------------------------------- 03-14
(Black Side Bars) Circuit Diagram and Explanation
Circuit Diagram Explanation
Circuit Diagram
---------------------------------------------------------------------------- 03-19
Circuit Diagram Explanation ----------------------------------------------------Circuit Diagram ---------------------------------------------------------------------
Circuit Diagram Explanation
Circuit Diagram
Voltages and Waveforms (Also, Not Running Info.)
Detection Circuit Diagram Explanation
Detection Circuit Diagram
Circuit Diagram Explanation
Circuit Diagram
Diagram
Diagram
(Digital Convergence Mode Functions)
(Digital Convergence Mode Functions)
(Digital Convergence Mode Functions)
Dimensions
Dimensions
Dimensions
Dimensions
Dimensions
Adjustment
----------------------------------------------------------------------------- 06-10
----------------------------------------------------------------------------- 06-11
----------------------------------------------------------------------------- 06-12
----------------------------------------------------------------------------- 06-13
----------------------------------------------------------------------------- 06-14
----------------------------------------------------------------------------------- 07-03
-------------------------------------------------------------------------------- 07-04
----------------------------------------------------------------- 03-18
------------------------------------------------------------------ 05-03
-------------------------------------------------------------------- 05-08
-------------------------------------------------------------------------- 05-09
-------------------------------------------------------------------------- 05-10
Circuit Diagram Explanation
Circuit Diagram DP-23, 23G, 26, 27 & 27D
Circuit Diagram DP-24
-------------------------------------------------------- 03-12
------------------------------------------------- 03-16
---------------------------------------------- 04-01
------------------------------------------------------------- 04-02
--------------------------------------------------- 05-01
---------------------------------------------- 05-05
------------------------------------------------------------- 05-06
---------------------------------------------------- 05-07
------------------------------------------ 06-06
Materials prepared by
Alvie Rodgers C.E.T.
------------------------------ 03-15
------------ 05-04
------------------------------ 06-01
----------------------- 06-05
DP-23, DP-23G & DP-24
DP-26
-------------------------- 06-08
DP-27
-------------------------- 06-09
-------- 06-07
03-20
03-21
Continued on Next Page
Table of Contents Page 2 of 4
Dec 2003 (ver f)
TOPICS PAGE
DP-2X TABLE OF CONTENTS
Materials prepared by
Alvie Rodgers C.E.T.
SECTION (7) ADJUSTMENT INFORMATION (Continued):
•
DCU Crosshatch Phase Settings ------------------------------------------------------------------- 07-05
•
Horizontal Position (Coarse)
•
Raster Tilt
•
Beam Alignment
•
Off-Set for Red and Blue Raster Position
•
Vertical Size
•
Horizontal Size
•
Beam Form
•
Lens Focus
•
Static Focus
•
DCU Character Set-Up
•
DCU Pattern (Sensor Position) Set-Up
•
43" Overlay
•
51" Overlay
•
57" Overlay
•
65" Overlay
•
Remote CLU5721TSI
•
Remote CLU5722TSI
•
Remote CLU4321UG
•
Read from ROM Notes ------------------------------------------------------------------------------ 07-24
◊
DIGITAL CONVERGENCE ALIGNMENT PROCEDURE
◊
(Clearing RAM)
◊
Centering Magnet
◊
Static Centering
◊
Green
◊
Red and Blue
◊
Green
◊
Red and Blue
◊
Green
◊
Red and Blue
◊
Storing
◊
Initializing Magic Focus Sensors ------------------------------------------------------------------- 07-34
◊
Convergence Touch Up
◊
ERROR CODES for DCU HD FOCUS Description -------------------------------------------- 07-36
•
Blue De-Focus
•
White Balance and Sub Brightness
•
White Balance
•
Sub Picture (PIP) Amplitude
•
Horizontal Position (Fine)
•
Magnet Locations ------------------------------------------------------------------------------------- 07-42
Adjustment
Adjustment
Adjustment
Adjustment
Adjustment
Adjustment
Adjustment
Dimensions
Dimensions
Dimensions
Dimensions
(Digital Convergence Mode Functions)
Clearing Digital Convergence Data
Adjustment
Adjustment (Freeze Button)
Mode Adjustment
3X3
Mode Adjustment
3X3
Mode Adjustment
7X5
Mode Adjustment
7X5
Mode Adjustment
9X13
Mode Adjustment
9X13
Digital Convergence Data (
Adjustment
Adjustment Flow Chart
Adjustment
------------------------------------------------------------------------------- 07-07
------------------------------------------------------------------------ 07-08
----------------------------------------------------------------------------- 07-10
-------------------------------------------------------------------------- 07-11
------------------------------------------------------------------------------ 07-12
------------------------------------------------------------------------------- 07-13
------------------------------------------------------------------------------ 07-14
and
DCU Data Confirmation
----------------------------------------------------------------------------- 07-17
----------------------------------------------------------------------------- 07-18
----------------------------------------------------------------------------- 07-19
----------------------------------------------------------------------------- 07-20
(Digital Convergence Mode Functions)
(Digital Convergence Mode Functions)
---------------------------------------------------------------------- 07-25
------------------------------------------------------------------------ 07-27
------------------------------------------------------------------------ 07-29
----------------------------------------------------------------------- 07-31
Minor Adjustments
--------------------------------------------------------------------------- 07-37
Adjustment
Adjustment
--------------------------------------------------------- 07-06
Adjustment
Adjustment
------------------------------------------------------ 07-26
--------------------------------------------------------------- 07-28
--------------------------------------------------------------- 07-30
-------------------------------------------------------------- 07-32
Write to ROM) ---------------------------------------------- 07-33
------------------------------------------------------ 07-35
Adjustment
------------------------------------------------------------ 07-39
--------------------------------------------------------- 07-40
------------------------------------------------------------- 07-41
----------------------------------------- 07-09
Adjustment
--------------------------------------------- 07-16
--------------------------------- 07-21
--------------------------------- 07-22
---------------------------------- 07-23
-------------------------------------------- 07-25
------------------------------------------------- 07-38
-------------------------- 07-15
------------------------------ 07-25
Continued on Next Page
Table of Contents Page 3 of 4
Dec 2003
SECTION (8) MISCELLANEOUS IN FOR MATI O N:
•
•
•
•
•
•
•
•
•
•
SECTION (9) THINGS YOU SH OULD KNOW / SERVICE BULLETINS / ETC ….:
•
•
(ver f)
TOPICS PAGE
Rear Panel
Rear Panel
Rear Panel
Rear Panel
Signal PWB
Deflection PWB
Power Supply PWB
CRT PWBs
All but DP-24
DP-24
Front Control PWBs
This section changes often, the index for this section is shown on the
Things You Should Know section divider.
Please go to Section 9 section divider cover page for details -------------------------------------
Download this Section Separately.
DP-2X TABLE OF CONTENTS
DP-27 and DP-27D (Terminal Input) Drawing
DP-23 and DP-23G (Terminal Input) Drawing
DP-26 (Terminal Input) Drawing
DP-24 (43FWX20B Only Terminal Input) Drawing
Drawing
Drawing
Front Control PWBs
--------------------------------------------------------------------------------- 08-05
Drawing
---------------------------------------------------------------------------- 08-06
Drawing
---------------------------------------------------------------------------------- 08-08
----------------------------------------------------------------------- 08-07
Drawing
Drawing
----------------------------------------------------- 08-03
---------------------------------------------------- 08-09
-------------------------------------------------------------- 08-10
-------------------------------------- 08-01
-------------------------------------- 08-02
------------------------------- 08-04
Materials prepared by
Alvie Rodgers C.E.T.
09-00
Table of Contents Page 4 of 4
POWER SUPPLY
INFORMATION
DP-2X
CHASSIS DIAGRAMS
SECTION 1
THIS PAGE LEFT BLANK
DP-2X +6V POWER SUPPLY REGULATION EXPLANATION
+6V Power Supply Circuit Diagram explanation:
(See DP-26, DP-27 and DP-27D +6V Regulation Circuit Diagram for details).
(Also, see DP-23, DP-23G and DP-24 +6V Regulation Circuit Diagram for details).
Note: Items described below for the DP-23, 23G and DP-24 are shown in brackets [ ].
THIS POWER SUPPLY RUNS ALL THE TIME:
When a Projection set is plugged into an AC outlet, it must produce a power supply to energize certain circuits.
These circuits are responsible for monitoring the Infrared input or Front control Keys as well as the Auxiliary
inputs if the Auto Link feature is active.
These power supplies are generally labeled as Always power supplies or Standby power supplies. As an example
would indicate a +6V power supply that’s always present. If the power supply has an Sby prefix, (example
A+6V
Sby +6V) this too is always present if the set is plugged into the AC outlet.
The DP-2X power supply Standby voltages are regulated by monitoring the
Sby +5V
The
by
REGULATION:
The primary route for the
However, the regulation route is to pin 1 of
the
pin 4 to pin 3 ground. This action causes pin 6 of
turn causes the frequency of the drive pulse delivered to the Gate of the internal SMOSFET (Switch Metal Oxide
Semiconductor Field Effect Transistor) to manipulate the frequency of the pulse generated on the primary of
T901
internally to pin 2 and then to floating ground pin
low ohm resistors,
SMOSFET is monitored. If this current exceeds a specific value, the voltage developed by these low ohm resistors is routed back into pin 5 which is the Over Current Protection circuit. This pin will inhibit the drive signal to
the gate of the SMOSFET. As soon as the excessive current situation is eliminated, the IC will recover and continue functioning.
B+ GENERATION FOR THE LOW VOLTAGE POWER SUPPLY DRIVER IC:
Vcc for the Driver IC is first generated by the AC input. This voltage is called Start Up Voltage.
16V
When AC is applied, AC is routed through the main fuse
to prevent any internal high frequency radiation for radiating back into the AC power line. After passing the filters it arrives at the main full wave bridge rectifier
supplied to the power supply switching transformer
However, one leg of the AC is routed to a half wave rectifier
R907
of
begins the operation of
When the power supply begins to operate by turning on and off the internal Switch MOS FET, the Raw 150V DC
routed through
Switch MOS FET is routed out of pin 2 through three low ohm resistors to hot ground. When the internal Switch
MOS FET turns on, it causes the transformer to saturate building up the magnet field. When the internal Switch
MOS FET turns off, the magnet field collapses and the EMF is coupled over to the secondary windings, as well
as the drive windings. The drive windings at pin
D905
Note too that Hot Ground is the Negative Leg of the bridge rectifier
T901.
after it is regulated by
Control +6V
and becomes a
C954
Control +6V
. Pin
DC to operate normal. However, it will begin operation at
(both a 68K ohm resistor), filtered by
as start up voltage. When this voltage reaches 6.8Vdc, the internal Regulator of
I901
, filtered by
is generated on the Secondary of
Power Supply.
+6V
Note: Items for the DP-23, 23G and DP-24 are shown in brackets [ ].
Control +6V
voltage fluctuations. The internal receiver receives this light and acts as a variable resistor from
6 [3]
of
T901
is routed to pin 1 of
T901
R908, R909
.
I901
, to
C911
in on pin 1 (Drain) and out on pin 2 which is the Source. The Source of the internal
I901
then routed clamped by
.
I909
is to pin 3 of
and
R910 [R908, R909
I904
I901
C911
The Primary Chassis Discussed is the DP-27 and DP-27D.
Control +6V
pin
T901
and output as
I909
. Internally, the LED is illuminated by degrees dependant upon
to manipulate the internal oscillator within
I901
which is the Drain of the SMOSFET. The source is connected
of
9 [6]
, clamped by a 30V Zener
8 [5]
D907
T901
] to hot ground. Here, the current drain of the internal
F901
where it is converted to Raw 150V DC voltage to be
D901
pin 2 [1].
T901
of
T901
and now becomes run voltage (
. The pulse is rectified by
10 [7]
Sby. +5V
. The floating ground is monitored by three [two]
6.8V DC
(a 6 Amp fuse), then through the Line filter
D904
produce a run voltage pulse which is rectified by
on pin 3 of
where it is rectified, routed through
and made available to pin (3)
D907
and the Floating Ground is pin
D901
which becomes the
from pin 2.
.
I901
is turned On and
I901
) for
16V
D941
I901
I901
I901
and filtered
. This in
requires
L901
R906
pin 3.
9 [6]
and
of
PAGE 01-01
DP-26, DP-27 and DP-27D CHASSIS POWER SUPPLY Sby +6V REGULATION
Lo Voltage Power Supply
T902
AC
8
C910A
R917
D953
D901
F902
2
T901
150V
6
D908
C918
R958
D904
R957
R906
16.3V
1
D
I901
Driver/
Output IC
6
FB/OLP
ABS
R916
C917
2
1
Regulator Photocoupler
4
R907
3
C915
FB
I904
Osc B+
BD
OCP
S
Start Up
7
5
2
4
3
C911
D906
R915
Run
D905
D907
R908
R909
R910
9
0.47
Ohm
R913
D910
R911
R912
C914
Hot Ground from
negative leg of
Bridge D901
Floating Ground
from pin 9 of T901
Cold Ground Pin 11
Secondary of
T901
C916
R914
Control
T901
10
11
+6V
C969
D941
C954
1.79A
C904
I909
3 2
+5V
Reg
C985C972 C973
1
0.0685A
PPS3
2
Sby +5V
PAGE 01-02
AC
DP-23, DP- 23G and DP-24 Chassis
+6.0 V Low Voltage Regulation
T901
5
C910A
R917
D901
F902
1
T901
150V
3
D908
C918
D904
C913
R916
C917
R906
1
6
R907
16.3V
3
Osc B+
D
I901
Driver/
Output IC
FB/OLP
ABS
4
BD
OCP
C915
Start Up
7
5
2
S
R908
R909
0.47
Ohm
FB
C911
D906
D905
D907
6
Run
R912
C914
Hot Ground from
R913
D910
R911
negative leg of
Bridge D901
C916
R914
D953
Control
T901
+6V
7
8
R958
C969
D941
C954
2
I904
1
R957
Regulator Photocoupler
C904
1.79A
3 2
R915
4
3
Cold Ground from
pin 8 of T901
I909
+5V
Reg
C972 C973
C985
1
Floating Ground
from pin 6 of T901
PPS3
0.0685A
2
Sby +5V
PAGE 01-03
DP-2X POWER ON RELAY CONTROLS EXPLANATION
Relay Controls Circuit Diagram explanation:
(See DP-23, DP-23G, DP-24 and DP-27, DP-27D Relay Controls Circuit Diagram for details)
POWER ON:
When the Customer presses the Power On button on the Front control panel or the Remote control, the Microprocessor
and it’s collector connected to the Sty +5V line goes low. This action in turn causes the base of
and turns
5V.
This high is routed to the
(See the Lo Voltage Power Supply Shut Down Circuit for details), then the High from pin 4 is routed to the base
of
Q908
When
Q908
the base of
RELAYS ENERGIZED BY Q907 (DP-23, DP-23G, DP-24, DP-27 and DP-27D:
Note: This description refers specifically to the DP-27 and DP-27D chassis. Components identified inside brackets [ ] are for the DP-23, 23G and DP-24 chassis.
S901
This completes the path for AC to reach the High Voltage power supply bridge diode
age Regulation Circuit for details). This action starts the High Voltage power supply
circuit.
S902
This completes the path for the pulse generated from pin
and [+29V for DP-23, DP-23G and DP-24] to reach the Audio B+ rectifier diode
is generated and output from the
[+29V]
S903
This completes the path for the pulse generated from pin
which produces
and
IP53
S905
This completes the path for the pulse generated from pin
rectifier diode
Tuners pin 9.
DP-26 ONLY: RELAYS ENERGIZED BY POWER _1 and POWER _2:
(See DP-26 Relay Controls Circuit Diagram for details)
Power _1: (High when the Set is turned On.)
• When the Customer presses the Power On button on the Front control panel or the Remote control, the
• This high is routed to the
• When
output a High from pin 59. This high is routed to the base of
I001
to turn Off.
Q025
PPS3
turning it On.
turns on, it’s collector is connected to the
turning it On. When
Q907
SW+6V
(Switched +5V regulator) on the Signal PWB.
D943
Microprocessor
transistor On and it’s collector connected to the Sty +5V line goes low. This action in turn causes the
base of
line and it’s collector pulls up to 5V.
tivated, (See the Lo Voltage Power Supply Shut Down Circuit for details), then the High from pin 4 is
routed to the base of
Q025
Q907
to reach the
. Here the
I001
to go low and turns
turns on, it causes the following relays to energize.
collector is also connected to the
Q025
connector pin 4. Provided the
Q907
PPS5
PPS4
SW+35V
output a High from pin 59. This high is routed to the base of
Q907
is generated and output from the
connector pin 4. Provided the
PPS3
turning it On.
which turns this transistor On
Q026
Q025
Sby +5V
Short Detection
Sby +5V
turns on, it causes the following relays to energize.
connector pins 1, 2 and 3 and on to the Audio output circuit.
connector pins 7 and 6 and on to
to turn Off.
Q025
line. It’s emitter pulls up and supplies a high to
of
14 [11]
10 [7]
13 [10]
T901
of
T901
of
T901
collector is also connected to the
Q025
line and it’s collector pulls up to
transistor
D902
SW+115V
, (+38V for DP-26, DP-27 and DP-27D)
. Here the
D944
(Control +6V), rectified by diode
(Switched +3.3V regulator)
IP52
(+35V) to reach the Tuning Voltage B+
connector pin 8 and on to the
PPS3
Short Detection
isn’t activated,
Q903
. (See the High Volt-
for the deflection
Audio +38V
which turns this
Q026
transistor
to go low
Sby +5V
isn’t ac-
Q904
D941
(Continued on page 5)
PAGE 01-04
DP-2X POWER ON RELAY CONTROLS EXPLANATION
RELAYS ENERGIZED BY Q907: Activated by Power _1
•
•
•
Power _2: (High when the set is turned On and/or when the Timer is On).
RELAYS ENERGIZED BY Q909
•
•
TIMER (Unattended Recording) OPERATION:
NOTE: Power _2
Tuners, Selector IC and Monitor output become active. During this time,
This way, the Selector IC, Tuners, Audio Circuit and Monitor outputs remain active.
The Table below shows the logic state of Power _1 and Power _2.
S901
This completes the path for AC to reach the High Voltage power supply bridge diode
High Voltage Regulation Circuit for details). This action start the High Voltage power supply
SW+115V
S902
This completes the path for the pulse generated from pin 14 of
tifier diode
and on to the Audio output circuit.
3
S903
This completes the path for the pulse generated from pin 10 of
D941
+3.3V regulator) and
• When the Customer presses the Power On button on the Front control panel or the Remote control, the
Microprocessor
• DM +9V REGULATOR:
• When Power _2 goes high, it's routed to pin 2 of
tor and it turns on. Input to pin 5 is the
to the Digital Module (ATSC Tuner) pin 12 PMS1.
3
• The DM +9V is also routed to the Terminal PWB pin 21of the
tor IC
• Power _2 is also routed to the
to the base of
• When
S905
This completes the path for the pulse generated from pin 13 of
age B+ rectifier diode
and on to the Tuners pin 9. This voltage is also routed out the PPS7 connector pin 6
come tuning voltage for the Digital Tuner (ATSC) via pin 1 of the
S906
This completes the path for the pulse generated from pin
rectifier diode
and on to the DM +9V regulator
from pin 3 to the Digital Module (ATSC Tuner) pin
for the deflection circuit.
, (+38V) to reach the Audio B+ rec-
T901
. Here the
D944
which produces
I001
and the Monitor Out Circuit.
IX01
Q909
turns on, it causes the following relays to energize.
Q909
D945
is also high when the Timer is set for unattended recordings. When the Timer is activated, the
Audio +38V
SW+6V
IP53
output a High from pin 58. This high is routed to two different circuits.
turning it On.
D943
. Here the
to reach the
(Switched +5V regulator) on the Signal PWB.
PPS3
: Activated by Power _2
. Here the
DM +10V
is generated and output from the
(Control +6V), rectified by diode
T901
connector pins 7 and 6 and on to
PPS4
on the Signal PWB. This is the
IP01
DM +10V, IP01
connector pin 4 and then to the Power Supply. This high is routed
SW+35V
. Input to pin 5,
IP01
is generated and output from the
is generated and output from the
regulates this down to 9V and output it from pin
connector. This turns on the Selec-
PST2
(+35V) to reach the Tuning Volt-
T901
PMS2
Digital Module +10V) of
17 (
regulates this down to
IP01
12
of the
PMS1
connector.
Power_1
connector pins 1, 2 and
PPS5
IP52
PPS3
connector.
connector pin 2 and 3
PPS7
+9V
remains Low.
. (See the
D902
(Switched
DM +9V
connector pin 8
DM +28V
T901
and outputs it
regula-
, to be-
to reach the
MODE POWER _1 POWER _2
Stand By L L
Timer L H
Power ON H H
PAGE 01-05
I001
59
Micro
Audio + 29V
Audio Gnd
Audio Gnd
Audio Gnd
Audio Gnd
1
2
3
4
5
6
7
PPS5
1.30A
D965
R985
GREEN L.E.D.
C978
L922
L921
R992
Sby 5V comes from I909 pin 2
SW + 35V
8
PPS3
0.0165A
Gnd
3
C956
Gnd
7
Sby +5V
4
2
POWER _1
R962 R963
Q908
Q025 Q026
On
R961
C957
Off
SW + 6V
Gnd
Gnd
6
7
5
Gnd
4
3
PPS4
Short Det.
See Power Supply Shut Down Circuit
1.33A
Q903
Sby +5V
L923
AC to D902
High Voltage
Power Supply
D943
C962
D944
C957
DP-23, DP-23G and DP-24 Chassis Power On Relay Controls
C961
R960
R959
Q907
Off
Supply Relay
S-902 Audio Power
E911
11
+29V
T901
Sby +5V
12
Supply Relay
S-905 SW +35V
10
+35V
On
D954
8
T901
Supply Relay
S-903 SW +6V
Control +6V
S-901 Main
Power Relay
AC
D941
C959
C954
7
PAGE 01-06
Sby 5V comes
from I909 pin 3
_2
POWER
_1
POWER
MODE
L
H
L
L
Timer
Stand By
H
H
TV On
From Micro Pin 58
From I909
On
From Micro Pin 59
From I911
On
Audio + 38V
Audio Gnd
Audio Gnd
Audio Gnd
Audio Gnd
1
2
3
4
5
6
7
PPS5
1.55A
R985
D965
GREEN L.E.D.
DP-26 RELAY CONTROLS
L922
C978
L921
R992
DM +10V
2
1.55 A
DM +10V
Sby +10V
1
3
0.36 A
From D942
DM +28V
Audio Gnd
Audio Gnd
4
5
6
0.006 A
Q909
N/C
7
PPS7
R973
R963
C968
R984
Off
POWER _2
5
PPS3
C956
SW + 35V
1
1.30A
0.25 A
SBY + 5V
Gnd
3
2
R960
POWER _1
Gnd
7
4
R962 R963
Off
PPS4
Q904
C957
D972
SW + 9V
1
SW + 6V
6
7
2
1.06A
1.54A
Short Det.
Shut Down Circuit
See Power Supply
Sby +5V
L923
Gnd
5
Gnd
Gnd
4
3
AC to D902
High Voltage
Power Supply
D944
S-902
SW +35V Relay
E911
14
+38V
Audio
C952
T901
C957
Sby +5V
15
D945
S-906 Digital
Module 10 V Relay
E912
17
C963
16
T901
C958
Sby +5V
D943
Supply Relay
S-905 SW +35V
13
+35V
C961
Off
On
Q907
D954
T901
R959
11
Supply Relay
S-903 SW +6V
Control +6V
10
S-901 Main
Power Relay
D941
C954
C959
PAGE 01-07
AC
I001
59
Micro
Audio + 38V
Audio Gnd
Audio Gnd
Audio Gnd
Audio Gnd
1
2
3
4
5
6
7
PPS5
1.95A
D965
R985
GREEN L.E.D.
C978
L922
L921
R992
Sby 5V comes from I909 pin 3
SW + 35V
8
PPS3
0.0165A
Gnd
3
C956
Gnd
7
Sby +5V
4
2
POWER _1
R962 R963
Q908
Q025 Q026
On
R961
C957
Off
SW + 6V
Gnd
Gnd
6
7
5
Gnd
4
3
PPS4
Short Det.
See Power Supply Shut Down Circuit
1.33A
Q903
Sby +5V
L923
AC to D902
High Voltage
Power Supply
C961
R960
R959
Supply Relay
S-903 SW +6V
D944
C962
C957
D943
Q907
Off
DP-27 and DP-27D CHASSIS RELAY CONTROLS on the POWER SUPPLY
Supply Relay
S-902 Audio Power
E911
14
+38V
T901
Sby +5V
15
Supply Relay
S-905 SW +35V
13
+35V
On
D954
11
Control +6V
10
D941
S-901 Main
Power Relay
C959
AC
C954
PAGE 01-08
DP-2X LOW VOLTAGE POWER SHUT DOWN EXPLANATION
Low Voltage Power Supply Shut Down Circuit Diagram explanation:
(See DP-27 Signal Power Supply (Low Voltage) Shut-Down Circuit Diagram for details)
The Low Voltage power supply is centered around the Switching Transformer
This power supply creates the Standby voltages
let. It also creates other voltages that are Switched on when the Set is turned on.
Audio +38V
SW +35V
SW +9V
SW +HVcc
The following explanation will describe the Low Voltage Power Supply Shut Down Circuit.
POWER SUPPLY SHUTDOWN PHOTO COUPLER I905 EXPLANATION
This chassis utilizes I901 as the Osc.\Driver \Switch for the Low Voltage power supply, just as the previous chassis have done. The Shutdown circuit, (cold ground side detection), removes
circuit,
signal to the Hot Ground side,
it removes B+ from pin (3) of
The Power Supply utilizes a Shutdown circuit that can trigger
tection circuits are not operational in Stand By mode).
forward biases the internal LED. The light from this internal LED is then coupled to the receiver transistor. The
receiver transistor turns On and output a High from pin 3. This high is routed to the base of
which grounds out the Vin at pin (3) of
Q902
The individual Shut Down circuits will be discussed later.
GENERAL INFORMATION:
All of the Power Supply Shutdown circuitry can be broken down into the following category;
•
•
•
•
The following will explain all of these commonly used circuits. The Service Technician should become familiar
with the appearance of these circuit and their function.
VOLTAGE LOSS or SHORT DETECTION
(See Figure 1)
One circuit used is the
cuit. This is a very simple circuit that detects a loss of
a particular power supply and supplies a Pull-Down
path for the base of a PNP transistor.
This circuit consist of a diode connected by its cathode to a positive B+ power supply. Under normal
conditions, the diode is reversed biases, which keeps
the base of Q1 pulled up, forcing it OFF. However, if
there is a short or excessive load on the B+ line that’s
being monitored, the diode in effect will have a LOW
on its cathode, turning it ON. This will allow a current path for the base bias of Q1, which will turn it
ON and generates a Shutdown Signal.
(the Photo Coupler), which isolates the Hot ground from the Cold ground and couples the Shutdown
I905
on the hot ground side and
Q902
(the Vin pin).
I901
I901
as long as there is any voltage available at its Emitter.
Voltage Missing Detection or Short Detection
Voltage Too High Detection
Excessive Current Detection
Negative Voltage Loss Detection
Voltage Loss Detection
SBY +5V
, disabling the power supply.
cir-
which runs anytime the set is plugged into an AC out-
Q901
Q902
is activated by a Low being applied to pin 2, which
I905
Voltage
Loss
Detector
Figure 1
and
T901
B+ at pin 3 via the following
I901
which latches
from 2 input sources. (1 of these Short De-
Q901
Q902
will keep a high on the base of
I901.
on. When
turning it On,
Q902
Any Positive
B+ Supply
Q902
B+
is on,
Q1
Shut-Down Signal
(Continued on page 10)
PAGE 01-09
DP-2X LOW VOLTAGE POWER SHUT DOWN EXPLANATION
VOLTAGE TOO HIGH DETECTION
(See Figure 2)
Another circuit used is the
circuit. In the example shown in Figure 2, the
tion
zener diode
the voltage source rises too high, the voltage at the
divider center point will rise as well and trigger or fire
the zener diode which produces a Shutdown signal.
EXCESSIVE CURRENT DETECTION
(See Figure 3)
One very common circuit used in many Hitachi television products is the B+
circuit. In this circuit is a low ohm resistor in series
with the particular power supply, (labeled B+ in the
drawing). The value of this resistor is determined by
the maximum current allowable within a particular
power supply. In the case of Figure 1, the value is
shown as a
ohm value. When the current demand increases, the
voltage drop across the resistor increases. If the voltage drop is sufficient to reduce the voltage on the base
of the transistor, the transistor will conduct, producing
a Shutdown signal that is directed to the appropriate
circuit.
NEGATIVE VOLTAGE LOSS DETECTION
(See Figure 4)
The purpose of the Negative Voltage Loss detection circuit is to
compare the negative voltage with its’ counter part positive voltage. If at any time, the negative voltage drops or disappears, the
circuit will produce a Shutdown signal.
In Figure 5, there are two resistors of equal value. One to the
positive voltage, (shown here as +12V) and one to the negative
voltage, (shown here as -12V). At their tie point, (neutral point),
the voltage is effectually zero (0) volts. If however, the negative
voltage is lost due to an excessive load or defective negative
voltage regulator, the neutral point will go positive. This in turn
will cause the zener diode to fire, creating a Shutdown Signal.
SPECIFIC INFORMATION:
In addition, there are 7 Hot Ground side Shutdown inputs that are specifically detected by the main power driver
IC
HOT GROUND SIDE SHUT DOWN SENSING CIRCUITS. (Specific to I901).
LATCHED SHUT DOWN MONITORS:
1. (OVP)
2. (TSD)
3. (OLP) Over Load Protection monitors the difference between the Hot Ground and Floating Ground.
RECOVERING SHUT DOWN INPUT:
4. (OCP)
. These sensors circuits protect
I901
is connected to a voltage divider. If
D1
0.47 ohm
is monitored for Over Voltage Protection at pin 3 of
Pin 3
itself is monitored for Excessive Heat. This block is labeled TSD. (Thermal Sensing Device).
I901
monitors the low ohm resistors,
Pin 5
Voltage Too High Detec-
Excessive Current Sensing
, however it could be any low
Voltage Too High
Detector
Shut-Down Signal
B+
Current Sensor
Figure 3
R1
0.47
Shut-Down Signal
Shut-Down Signal
Any Positive
Voltage
Loss
Detector
from excessive current, temperature or over voltage.
I901
(AC must be removed to recover).
(Driver IC will recover on it’s own when trouble is removed.)
R908, R909,
and
Figure 4
.
I901
. If these resistors have an excessive
R910
+12V -12V
(Continued on page 11)
B+ Supply
Figure 2
Base
Bias
PAGE 01-10
DP-2X LOW VOLTAGE POWER SHUT DOWN EXPLANATION
current condition caused by monitoring the current through the internal Switch MOS FET, the voltage will
rise and pin 5 has an internal Over Voltage detection op-amp. If this voltage rises enough to trigger this opamp, the IC will stop producing a drive signal.
5. (ABS)
of High Voltage.
6. (BD)
COLD GROUND SIDE SHUT DOWN SENSING CIRCUITS.
(See DP-27 Signal Power Supply (Low Voltage) Shut-Down Circuit Diagram for details)
Looking at Pin 2 of
D963, D962:
The cathode of
connected directly to the
this line down,
a Shut Down event. See Power Supply Shutdown Photo Coupler I905 Explanation on the previous page.
Q910:
This transistor’s base is connected to
the Shut down enable circuit.
DP-27 SHUT DOWN CIRCUIT:
There are a total of 3 individual Shutdown inputs to the photo coupler
There are a total of 3 individual Shutdown inputs to the Relay Inhibit transistor
There are a total of 4 individual Shutdown inputs to the Relay Inhibit transistor
cuit. For a total of 10 individual Shutdown inputs that will kill the Lo Voltage Power Supply. (Note: The Hi Volt-
age Power Supply Shutdown will be discussed later.)
All of the Cold Ground side Shutdown detection circuits can be categorized by the two previously described circuits
In the following explanation, the Shutdown circuits will be grouped. This will assist the Service Technician with
trouble shooting the Chassis, by understanding these circuits and having the associated circuit routs, the technician can then “Divide and Conquer”.
Voltage Loss Detection through I905 Photo coupler
• Shorted STBY +3.3V generated by
to (
• Shorted SW+2.2V (
on Low Voltage Power Supply PWB. Labeled
• Shorted SW+3.3V (
(
• Shorted SW+5V (
(
Q903 Relay Inhibit Activation.
From the Power Supply.
SW +115V Voltage Too High Detection
• Monitored by (
SW +115V Excessive Current Detection
• Monitored by (
also has
Pin 4
Monitors the Run Voltage generated by pin 18 of
Pin 7
I905
is connected through
D963
would forward bias and supply a current path for pin 2 of
D963
) on Low Voltage Power Supply PWB. Labeled
D963
) on Low Voltage Power Supply PWB. Labeled
D961
) on Low Voltage Power Supply PWB. Labeled
D961
D927
Q905
monitoring spike current in case the CRTs “Snap” indicating a quick discharge
C915
the shut down events are triggered by two routes.
to pin 10 of
R982
power supply produced by
3.3V
through
Q911
pin 5) on Signal PWB monitored by
IP52
pin 2) on Signal PWB monitored by
IP52
pin 2) on Signal PWB monitored by
IP53
) See additional Shut Down Circuit Diagram for details.
) See additional Shut Down Circuit Diagram for details
D955. Q911
and monitored by (
IP81
IP81
PROT-SW
for excessive voltage.
T901
(AC must be removed to recover).
. This in turn is connected to
PPS3
on the Signal PWB. If something were to load
This in turn would produce
I905.
emitter is connected to
.
I905
Q903
Q903
) on Signal PWB through
R298
PROT-SBY
RP53
on the Schematic.
DP53, RP53
PROT-SW
DP54, RP53
PROT-SW
on the Schematic.
through
on the Schematic.
on the Schematic.
Q912
from the power supply.
from the Deflection Cir-
pin 11 to to (
PPS3
through
through
PPS3
PPS3
which is
R298
. This transistor is
pin 10
PPS3
D961
pin 11 to to
pin 11 to to
(Continued on page 12)
)
PAGE 01-11
DP-2X LOW VOLTAGE POWER SHUT DOWN EXPLANATION
SW –28V Loss Detection
• Monitored by (
From the Deflection Circuit PPD3 connector pin 6.
Vertical B+ 28V Voltage Excessive Current Detection
• Monitored by (
Excessive High Voltage Detection
• Monitored by (
-5V Loss Detection
• Monitored by (
Side Pincushion Failure Detection
• Monitored by (
If any one of these circuits activate the base of
connector pin 4 and the power supply will STOP.
SOME SHUTDOWN CIRCUITS ARE DEFEATED IN STANDBY MODE. (Set Off).
As indicated in the Power Supply (Lo Voltage) Shutdown circuit diagram, 3 of the shut down inputs are not active when the set is in standby.
• Shorted SW+2.2V (
on Low Voltage Power Supply PWB. Labeled
• Shorted SW+3.3V (
(
) on Low Voltage Power Supply PWB. Labeled
D961
• Shorted SW+5V (
(
) on Low Voltage Power Supply PWB. Labeled
D961
These voltage loss sensing circuits are defeated because the SW (Switched) power supplies are turned off in
standby. So to prevent faults triggering of the shutdown circuit, the sensing circuits are turned off also..
supplies the high for shutdown if any of the voltage loss circuits become activated.
Q911
voltage to operated. Emitter voltage is supplied from the emitter of
on/off line. When the set is not on or turned off, the power on/off line goes Low. This Low pulls the cathode of
low, removing the base voltage of
D956
this circuit can not function. The base of
for this circuit to function.
B+ GENERATION FOR THE LOW VOLTAGE POWER SUPPLY DRIVER IC:
Vcc for the Driver IC is first generated by the AC input. This voltage is called Start Up Voltage.
DC to operate normal. However, it will begin operation at
16V
When AC is applied, AC is routed through the main fuse
to prevent any internal high frequency radiation for radiating back into the AC power line. After passing the filters it arrives at the main full wave bridge rectifier
supplied to the power supply switching transformer
However, one leg of the AC is routed to a half wave rectifier
(both a 68K ohm resistor), filtered by
R907
of
as start up voltage. When this voltage reaches 6.8Vdc, the internal Regulator of
I901
begins the operation of
When the power supply begins to operate by turning on and off the internal Switch MOS FET, the Raw 150V DC
routed through
MOS FET is routed out of pin (2) through three low ohm resistors to hot ground. When the internal Switch MOS
FET turns on, it causes the transformer to saturate building up the magnet field. When the internal Switch MOS
FET turns off, the magnet field collapses and the EMF is coupled over to the secondary windings, as well as the
drive windings. The drive windings at pin (8) produce a run voltage pulse which is rectified by
then routed clamped by
C911
T901
) See additional Shut Down Circuit Diagram for details
D937
) See Deflection Protect Power Supply Shutdown Diagram for details.
Q604
) See Deflection Protect Power Supply Shutdown Diagram for details.
DH15
) See Deflection Protect Power Supply Shutdown Diagram for details.
DK90
D702, D703
IP53
.
I901
, in on pin 1 (Drain) and out on pin 2 which is the Source. The Source of the internal Switch
) See Deflection Protect Power Supply Shutdown Diagram for details
will go High and remove the Power On High from
Q903
pin 5) on Signal PWB monitored by
IP52
PROT-SW
pin 2) on Signal PWB monitored by
IP52
pin 2) on Signal PWB monitored by
turning it OFF. This removes the emitter voltage from
Q912
is also connected to the
Q912
F901
where it is converted to Raw 150V DC voltage to be
D901
pin (2).
T901
D904
, clamped by a 30V Zener
C911
and now becomes run voltage (
D907
on the Schematic.
PROT-SW
DP54, RP53
PROT-SW
Q912. Q912s
6.8V DC
(a 6 Amp fuse), then through the Line filter
where it is rectified, routed through
16V
through
RP53
DP53, RP53
on the Schematic.
on the Schematic.
SW +6V
on pin (3) of
D907
) for
through
through
base is connected to the power
line. This voltage must be active
and made available to pin (3)
pin 3.
I901
PPS3
Q911
I901
I901
PPS3
pin 11 to to (
PPS3
pin 11 to to
PPS3
requires emitter
I901
.
is turned On and
D905
D961
pin 11 to to
Q911
requires
R906
, filtered by
)
and
L901
and
PAGE 01-12
DP-2X SIGNAL POWER SUPPLY (Low Voltage) SHUT-DOWN CIRCUIT
D904
R906
R907
16.97V
T901
D905
D941
8
10
Control +6V
C911
AC
Monitors
SW +5V
SW +3.3V
SW +2.5V
and
Stby +3.3V
for Short
To R298
Monitors IP81
To RP53
Monitors IP52
and IP53
Sby +5V
S901
Relay
AC
To Hi Volt
Power
Supply
D954
HZS11B1
Protect _Def
4 from Deflection
See Deflection Shut
Down Circuits
Q907
16.3V
Q901
S-905
SW +35V
Supply
Relay
R960
R959
6
PPD3
Vin
3
I901
Power IC
Q902
C920
R921
Protect _Sby
3.3V Reg
Protect _Sw
+5V Reg
SW +35V
Q908
C957
Q904
D933
R940
C944
R919
C919
47 Ohm
R920
PPS3
10
11
R980
8
D946
See Relay Control
Diagram for all
Relay Controls
R962
R962
1K
C987
Q903
R938
D907
R922
D962
HZS3C1
D963
R982
D960D961
D957
4
R963
220
R939
10K
R913
I905
HZS4A1
C956
9
11
R956
1
23
Q910
C969
Q911
R967
R966
C970
SW +35V
R969
D956
C971
PPS3
Power _1
4
Off
On
See additional
Power Supply Shut
Down Circuits
A
C955
D952
D955
Q912
+6V
S-903 SW +6V
Supply Relay
2
R964
R965
SW +6V
R968
I909
Sby +5V
PAGE 01-13
DP-2X SW +115V POWER SUPPLY REGULATION EXPLANATION
Hi-Voltage Power Supply Circuit Diagram explanation:
(See DP-27 Chassis Power Supply SW+115V Regulation Circuit Diagram for details)
THIS POWER SUPPLY RUNS ONLY WHEN THE SET IS TURNED ON:
TURNING ON THE SW +115V POWER SUPPLY:
When the Set is turned on, the Microprocessor
command is routed through
provided the Short Detection Shut Down sensor
Q908
it’s emitter will go high and drive the base of
power on Relay
See Relay Controls on the Power Supply for details.
This rectifier develops raw 150V which is routed through
through the primary coil inside
Switch MOS FET. The Ground return path for the primary voltage is out pin 2 of
internal Switch MOS FET and then through three low ohm resistors
Regulation Circuit Diagram for details.
SW +115 REGULATION
SW +115V pulse is generated from pin 11 of
routed through the Excessive Current sensing circuit
The primary route for the
to the Deflection Circuit.
However, the regulation route is through
variable resistor whose resistance is dependant upon the
resistor manipulates the current flow from pin 2 to pin 3 ground. This will cause the voltage at pin 2 of
manipulated. Internally, the LED is illuminated by degrees dependant upon the
The internal receiver receives this light and acts as a variable resistor from pin 4 to pin 3 which is the regulation
control signal.
This action causes pin 1 of
quency of the drive pulse delivered to the Gate of the internal SMOSFET (Switch Metal Oxide Semiconductor
Field Effect Transistor) to manipulate the frequency of the pulse generated on the primary of
drain of the internal SMOSFET is monitored by the three low ohm resistors mentioned above. If this current exceeds a specific value, the voltage developed by these low ohm resistors is routed back into pin 1 which is the
Over Current Protection circuit as well as the Regulation Control pin. This pin will inhibit the drive signal to the
gate of the SMOSFET. As soon as the excessive current situation is eliminated, the IC will recover and continue
functioning.
B+ GENERATION FOR THE HIGH VOLTAGE POWER SUPPLY DRIVER IC:
Vcc for the Driver IC is first generated by the AC input. This voltage is called Start Up Voltage.
DC to operate normal. However, it will begin operation at
16V
When AC is applied to the main full wave bridge rectifier
to be supplied to the power supply switching transformer
However, one leg of the AC is routed to a half wave rectifier consisting of
sistor), filtered by
When this voltage reaches 6.8Vdc, the internal Regulator of
When the power supply begins to operate by turning on and off the internal Switch MOS FET, the Raw 150V DC
routed through
MOS FET is routed out of pin (2) through three low ohm resistors to hot ground. When the internal Switch MOS
FET turns on, it causes the transformer to saturate building up the magnet field. When the internal Switch MOS
FET turns off, the magnet field collapses and the EMF is coupled over to the secondary windings, as well as the
drive windings. The drive windings at pin (8) produce a run voltage pulse which is rectified by
then routed clamped by
C923
The RED LED
turning it on. When the relay is energized, AC is supplied to the Bridge rectifier
S901
SW +115V
, clamped by a 36V Zener
C923
, in on pin 1 (Drain) and out on pin 2 which is the Source. The Source of the internal Switch
T902
can be used to determine if the B+ to I902 is present or not.
D915
and
Q025
and out pins 5 and 6 to pin 3 of
T902
to manipulate the internal oscillator within
I902
and now becomes run voltage (
D912
to the
Q026
is through
E906
Outputs a Power On command via pin 59. This Power On
I001
PPS3
high turning it on. This will supply a ground path for the
Q907
. This pulse is rectified by
T902
E907, L914
to pin 1 of
D912
connector pin 4. This High will be passed to the base of
isn’t activated. When the base of
Q903
to Pins 1 and 2 of
F903
which is the Drain of the internal
I902
R926, R927
D915
and
R941
to pin 9 and 10 of
I907
SW +115V
D902
T902
and made available to pin 4 of
I902
.
Q905
. Internally, the regulator transistor works as a
voltage fluctuations. The internal variable
I902
6.8V DC
where it is converted to Raw 150V DC voltage
pin 1 and 2.
on pin 4 of
R924
is turned On and begins the operation of
) for
16V
I902
. This voltage is routed
T902
which is the Source of the
I902
and
, filtered by
PPD6
SW +115V
. This in turn causes the fre-
and
pin 4.
. See SW+115V
R928
and output as
voltage fluctuations.
.
I902
(both a 3.9K ohm re-
R925
as start up voltage.
I902
Q908
C927
. The current
T902
I902
D911
goes high,
D902
and then
SW +115V
I906
requires
, filtered by
.
to be
I902
.
PAGE 01-14
T902
DP-2X CHASSIS POWER SUPPLY SW +115V REGULATION
High Voltage Power Supply
8
7.5P/P
9
AC
From Relay S901
C923
AC for D902
Supplied from
Relay S901
From Bridge D902
150V
1
F903
2
D912
T902
D915
RED L.E.D.
R934
R924
16.3V
4
I902
Driver/
Output IC
3 2
DS
6
R925
OCP
Start Up
Osc B+
1
R929
R926
R927
R928
0.22
Ohm
Run
D911
R930
D914
R931
R932
C926
D913
I907
1 2
4
3
Regulator Photocoupler
I906
Hot Ground from
pin 9 of T902
R936
SW + 115V
R937FB
1
R935
2
D922
T902
11
12
C933
D915
C927
C945
X-Ray
Protect
5
6
Q905
R941
0.47 Ohm
D924
D925
D926
R943
R942
D927
E906
0.5K
3K
E907
R945
R946
L914
Deflection
B+ 115V
D928
C942
3
PPD6
0.69A
9
10
Cold Ground from
pin 12 of T902
C905
C941
SW +115V
SW +115V
PAGE 01-15
DP-2X ADDITIONAL SHUTDOWN CIRCUITS EXPLANATION
Additional Power Supply Shut Down Circuit Diagram explanation:
(See DP-27 Additional Power Supply Shut Down Diagram for details)
Use this explanation and Diagram in conjunction with the following diagrams.
DP-2X Signal Power Supply (Low Voltage) Shut Down Circuit (Continuation A)
The following circuits are routed to the Lo Voltage Shut Down Circuit through connection point (A) depicted on the Circuit drawing:
SW +115V EXCESSIVE CURRENT DETECTION
(See Figure 1)
One very common circuit used in many Hitachi television products is the B+
circuit. In this circuit is a low ohm resistor in series
with the SW +115V. The value of this resistor
. When the current demand increases, the voltage
ohm
drop across the resistor increases. If the voltage drop
is sufficient to reduce the voltage on the base of
, the transistor will conduct, producing a Shut-
Q905
down signal that is directed to the appropriate circuit
indicated on the drawing as point
NEGATIVE VOLTAGE LOSS DETECTION
(See Figure 2)
The purpose of the Negative Voltage Loss detection circuit is to
compare the negative voltage with its’ counter part positive voltage. If at any time, the negative voltage drops or disappears, the
circuit will produce a Shutdown signal.
In Figure 2, there are two resistors of equal value, (15K). One to
the positive voltage SW +28V and one to the negative voltage
SW –28V. At their tie point, (neutral point), the voltage is effec-
tually zero (0) volts. If however, the negative voltage is lost, the
neutral point will go positive. This in turn will cause the zener
diode D937 to fire, creating a Shutdown Signal through
and on to the appropriate circuit indicated on the drawing as
point
Note: The LED
supply.
VOLTAGE TOO HIGH DETECTION
(See Figure 3)
Another circuit used is the
tion
zener diode
the voltage source rises too high, the voltage at the
divider center point will rise as well and trigger or fire
the zener diode which produces a Shutdown signal
through
cated on the drawing as point
.
(A)
D940
circuit. In the example shown in Figure 3, the
D927
and on to the appropriate circuit indi-
D926
Excessive Current Sensing
0.47
.
(A)
used for visual trouble shooting is illuminated by the current draw from +28V to the –28V
Voltage Too High Detec-
is connected to a voltage divider. If
.
(A)
SW +115V
D936
Figure 3
Figure 1
Figure 2
SW +28V
D927
D926
0.47
R941
Current Sensor
Q905
Shut-Down Signal
Shut-Down Signal
Voltage
Loss
Detector
D940
Voltage Too
High Detector
Base
Bias
D936
D937
SW -28V
SW +115V
Shut-Down
Signal
PAGE 01-16
T902
DP-2X ADDITIONAL POWER SUPPLY SHUT DOWN DIAGRAM
C933
3K
E907
Deflection B+ 115V
D915
Q905
R941
0.47 Ohm
11
C927
12
Deflection B+ (115V)
Excessive Current Det.
See Signal Power Supply
(Lo Voltage)
Shut Down Circuit
Diagram
for continuation.
C945
R943
D924
R944
C946
D925
A
SW-28V Short or Loss Det.
R942
D927
D926
R945
R946
D936
D937
Deflection B+ (115V)
Excessive Voltage Det.
D928
Deflection B+ 115V
PPD6
L914
0.69A
9
10
SW +115V
SW +115V
T902
T902
15
13
14
10K
E901
10K
E902
C934
D917
C928
C935
D918
C929
-
+
+
-
D940
R952
D971
L913
L912
C950
C949
R951
-
+
+
-
L915
L916
0.575A
1.09A
5
3
4
1
2
SW -28V
Gnd
Gnd
SW +28V
SW +28V
PAGE 01-17
DP-2X PROTECT SHUTDOWN CIRCUIT EXPLANATION
0.68
DK90
.
SW +28V
Figure 1
through
.
D703
PPD3
and
DH15
R629
Current Sensor
Q604
through
pin 6.
DH13
.
DH14
to stop producing the Hi
IH01
0.68
Shut-Down Signal
pin 6. This signal is
PPD3
Shut-Down Signal
DK90
+5V -5V
and
Base
Bias
Voltage
Loss
Detector
Protect Shut Down Circuit Diagram explanation:
(See DP-27 Protect Shut Down Diagram for details)
Use this explanation and Diagram in conjunction with the following diagram,
DP-2X Signal Power Supply (Low Voltage) Shut Down Circuit (PROTECT _DEF)
The following circuits are routed to the Lo Voltage Shut Down Circuit through connection point
(PROTECT _DEF) depicted on the Circuit drawing:
EXCESSIVE HIGH VOLTAGE DETECTION
Whenever the High Voltage fluctuates, every other pin off the flyback will fluctuate as well. In this case, a lower
voltage source can be used to determine the status of the High Voltage.
Pin 5 (50P) is used to monitor for excessive High Voltage. The pulse off the flyback is rectified by
filtered by
is a HZ22V zener. If the voltage at the cathode rises too high, the zener will fire and send a Shut Down
DH15
signal through
The Shut Down signal is depicted as
is a HZ36V zener. If the voltage at the cathode rises too high, the zener will fire and send a Shut Down
DH14
signal through to pin 7 of
Voltage Drive signal from pin 1.
EXCESSIVE CURRENT TO THE VERTICAL OUTPUT IC DETECTION
(See Figure 1)
This circuit uses a low ohm resistor
with the SW +28V. The value of this resistor
. When the current demand increases, the volt-
ohm
age drop across the resistor increases. If the voltage
drop is sufficient to reduce the voltage on the base of
, the transistor will conduct, producing a Shut-
Q604
down signal through
signal is routed to the appropriate circuit on the Lo
Voltage Shut Down Circuit. The Shut Down signal
is depicted as
SIDE PINCUSHION FAILURE DETECTION
If the side pincushion circuit fails in such a way as to produce an excessive high on the cathode of D702 (a
HZS7C3) the zener will fire producing a Shutdown signal through
routed to the appropriate circuit on the Lo Voltage Shut Down Circuit. The Shut Down signal is depicted as
PROTECT _DEF
-5V LOSS DETECTION
The purpose of the Negative Voltage Loss detection circuit is to compare the
negative voltage with its’ counter part positive voltage. If at any time, the negative voltage drops or disappears, the circuit will produce a Shutdown signal.
In Figure 2, there are two resistors of equal value. One to the positive voltage
+5V and one to the negative voltage -5V). At their tie point, (neutral point), the
voltage is effectually zero (0) volts. If the negative voltage is lost, the neutral
point will go positive. This high is routed through
This signal is routed to the appropriate circuit on the Lo Voltage Shut Down Circuit. The Shut Down signal is depicted as
. This voltage sets on the cathode of two zener diodes
CH17
pin 6. This signal is routed to the appropriate circuit on the Lo Voltage Shut Down Circuit.
PPD3
PROTECT _DEF
which is the OVP input pin. This high will cause
IH01
in series
R629
through
D608
PROTECT _DEF
.
.
pin 6. This
PPD3
PROTECT _DEF
Figure 2
PAGE 01-18
DP-2X DEFLECTION PROTECT POWER SUPPLY SHUTDOWN DIAGRAM
RH32 allows ABL fluctuations to
manipulate the Trigger Point of Shut
Down as screen brightness varies. ABL
is inverse proportionate to brightness.
This prevents false triggering.
Active
Normal
PPD3
PROTECT _DEF
See Power Supply Shut Down
Circuit Diagram for continuation.
Vertical Output Circuit
I601
10
28V
75
Hi Volt
H. Drive
IH01
OVP
Flyback
High Voltage
ABL Voltage
Too High Det.
ABL
RH32
TH01
3
5OP
4
6
DH15
Excessive Hi
Voltage Det.
RH24
Any fluctuations in High Voltage will
also be reflected by the 50P output P/P.
By monitoring the 50P (50 Pulse) rises
in High Voltage will be sensed. If High
Voltage climbs too high, DH15 will fire
and trigger a shut down event.
Sensing Circuit
RH23
LH06
29.01V
CH17
DH13
RH26
DH14
Stops H. Drive
R629 0.68 Ohm
Q604
R630
C610
Excessive Vertical
Current Det.
If the Vertical Output IC has a problem,
R629 will sense the current rise. The
voltage drop will be reflected at the base
of Q604 turning it on and producing a
Shut Down high.
R631
D608
R632
D702 monitors the Side Pin
Drive IC. If the voltage at
pin 7 rises too high, D702
will fire generating a Shut
Down high.
D703
Convergence Out Circuit
RK97
-5V
RK98
DK90
A loss of the Negative 5V will cause the
positive 5V to be felt on the anode of
DK90 which forward biases the diode
and delivers a Shut Down high.
+5V
Side Pincushion Circuit
R717
D702
HZS7C3
Side Pin Failure
-5V Loss
Detection
I701
7
High Det.
PAGE 01-19
DP-2X LED (Visual Trouble Detection) CIRCUIT EXPLANATION
LED Used for Visual Trouble Shooting Circuit Diagram explanation:
(See DP-2X LED (Visual Trouble Detection) Diodes Signal Power Supply Diagram for details)
5 LEDS, 4 GREEN AND 1 RED
In the DP-2X chassis, there are 5 total LEDs that can be used for Visual Trouble shooting. 4 Green and 1 Red.
Use these LEDs to determine if the set is experiencing a problem.
The LEDs can be used in the following ways.
OFF:
• If the LED is off, then the power supply that is being monitored is unavailable. (Excluding the possibility
that the LED itself is malfunctioning). NOTE: If
tion because of it’s current flow explained below.
• If the LED turns on but then quickly goes off before the others, then the power supply that is being moni-
tored can be suspected.
RED LED D915
is used to monitor the Start Up and Run voltage for the Driver IC
D915
lowing voltages.
SW +115V
220V
HEATER
SW+7V
SW-7V
SW +28V
SW -28V
This LED is attached to pin 4 of
GREEN LEDs D965, D954, D940 and D928.
D965 (Audio +38V)
• Monitors the
D954 (SW +9V)
• Monitors the
pin 1 and 2.
D940 (SW +28V)
• Monitors the SW +28V output from the
• Note: This LED requires the SW –28V power supply to be functioning to operated. If the LED opens, or
the negative SW –28V is shorted, this LED will not illuminate and the set will shut down.
D928 (SW +115V)
• Monitors the
Audio +38V
SW +9V
SW +115V
. If the voltage is missing, the LED will not light.
I902
output from the
generated by the SW +9V regulator
PPD6
output from the
PPD6
LED opens, then the set will be in shut down condi-
D940
connector pin 1, 2 and 3.
PPS5
connector pin 1 and 2.
connector pin 9 and 10.
. This IC is used to generate the fol-
I902
pin 3 output from the
I911
PPS4
connector
PAGE 01-20
DP-23, DP-23G and DP-24 CHASSIS
L.E.D. (Visual Troubleshooting) Low Voltage Power Supply
(5 Total L.E.D. for visual trouble sensing , 4 Green and 1 Red)
T901
T901
T902
E911
11
12
Off
Power _1
E909
9
8
14
E902
+28V
13
S-902 Audio Power
Supply Relay
Sty +5V
On
PPS3
4
D942
C960
D918
C935
R990
1.92A
1.13A
C929
D944
C962
C957
- 28V
C955
L913
C950
1.55A
2
5
L922
R992
L921
I911
SW+9V
Reg
1
D940
R951
4
R952
3
R977
R976
GREEN L.E.D.
C978
GREEN L.E.D.
C977
GREEN L.E.D.
D937 D936
R979
L916
See Shut
Down Circuit
R985
D965
1.30A
L924
D954
0.57A
1.09A
PPS5
1
2
3
4
5
6
7
PPS4
1
2
3
4
5
PPD6
1
2
Audio + 29V
Audio Gnd
Audio Gnd
Audio Gnd
Audio Gnd
SW + 9V
Gnd
Gnd
Gnd
+ 28V
+ 28V
+115V D915
T902
11
12
C933
C927
Osc B+
AC
From
Relay
S901
C923
Hot Ground from
pin 9 of T902
Q905
C945
RED L.E.D.
R941 0.47 Ohm
R925R924
D912
D915
R934
Start Up
E907
+115V
Over
Current
D928
Run
D911
16.3V
4
I902
Driver/Output IC
6
L914
R945
R946
GREEN L.E.D.
R931
1
D913
0.69A
R930
7.5P/P
D914
4
3
R932
Regulator Photocoupler
From I907 pin 2 of
Regulator IC
9
10
6
Gnd
7
Gnd
From Pin 8 T902
I906
SW + 115V
SW + 115V
SW + 115V
1
R935
2
R922
PAGE 01-21
DP-26 CHASSIS
L.E.D. (Visual Trouble Detection) Diodes Signal Power Supply
(5 Total L.E.D. for visual trouble sensing observation, 4 Green and 1 Red)
T901
T901
T902
E911
14
15
Off
Power _1
E909
12
11
14
+28V
13
S-902 Audio Power
Supply Relay
Sby+5V
On
PPS3
4
D942
C960
D918
E902
C935
R990
1.92A
1.13A
C929
D944
C962
C957
- 28V
2
5
C976
L913
C950
1.55A
L922
R992
L921
I911
SW+9V
Reg
1
D940
R951
4
R952
3
R977
R978
GREEN L.E.D.
C978
GREEN L.E.D.
C977
GREEN L.E.D.
D937 D936
R979
L916
Down Circuit
1.55A
R985
D965
D954
See Shut
L924
0.67A
1.09A
PPS5
1
2
3
4
5
6
7
PPS4
1
2
3
4
5
PPD6
1
2
Audio + 38V
Audio Gnd
Audio Gnd
Audio Gnd
Audio Gnd
SW + 9V
Gnd
Gnd
Gnd
+ 28V
+ 28V
+115V D916
T902
11
12
C933
C927
Osc B+
AC
From
Relay
S901
C923
Hot Ground from
pin 9 of T902
Q905
C945
RED L.E.D.
R941 0.47 Ohm
R925R924
D912
D915
R934
Start Up
E907
+115V
Over
Current
D928
Run
D911
16.3V
4
I902
Driver/Output IC
5
L914
R945
R946
GREEN L.E.D.
R931
1
D913
0.69A
R930
7.5P/P
D914
4
3
R932
Regulator Photocoupler
From I907 pin 2 of
Regulator IC
9
10
6
Gnd
7
Gnd
From Pin 8 T902
I906
SW + 115V
SW + 115V
SW + 115V
R937
1
R935
2
D922
PAGE 01-22
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