Daewoo DQD-2100D User manual

S/M No. : VD6100NET0
Service Manual
MODEL :DQD-6100D
DQD-2100D
DAEWOO ELECTRONICS CO., LTD.
Jun. 2002
http : //svc.dwe.co.kr
✔ Caution
: In this Manual, some parts can be changed for improving, their
performance without notice in the parts list. So, if you need the
latest parts information,please refer to PPL(Parts Price List) in
Service Information Center (http://svc.dwe.co.kr).

EXTERNAL VIEWS .........................................................................................................2
1. FRONT VIEWS ........................................................................................................................ 2
2. REAR VIEWS............................................................................................................................2
SPECIFICATIONS...........................................................................................................3
CIRCUIT DIAGRAM....................................................................................................................4
CIRCUIT OPERATIONAL DESCRIPTION ...............................................................................13
TROUBLE SHOOTING..............................................................................................................26
WAVEFORMS............................................................................................................................36
COMPONENTS LOCATION GUIDE ON PCB BOTTOM VIEW............................................45
DISASSEMBLY.........................................................................................................................47
ELECTRICAL PARTSLIST.........................................................................................................51
1
CONTENTS

1. FORNT VIEWS
1)DQD-2100D
2) DQD-6100D
2. REAR VIEWS
1) DQD-2100D
2) DQD-6100D
2
EXTERNAL VIEWS
EURO AV
DIGITAL AUDIO OUT
AUDIO OUT (2 CH) VIDEO OUT
EURO AV
DIGITAL AUDIO OUT
AUDIO OUT (5.1 CH) AUDIO OUT (2 CH) VIDEO OUT

3
SPECIFICATIONS
1. Prodcut features
- Over 500 resolution of horizontal frequency
- Disc playback of DVD, VCD, CD, CD-R, CR-RW
- Dolby Digital decoding
- 5.1ch Analog signal output(6100, 6101)
- DTS output
- Screen zoom function
- Special playback function(slow playback/fast playback)
- Component output(Y, Cr, Cb)
2. Specifications
Basic spec orizontal frequency over 500 resolution
available disc DVD, CD, VCD, CD-R, CD-RW, DVD-R
Audio Dolby Digital Analog 5.1ch output and digital output
DTS Digital output
Convenience Screen zoom function OK
Volume control function OK
Special playback function OK
MP3 playback function OK
Connecting terminal Video terminal Composite terminal : 2 unit
Component terminal : 1 unit
S-VHS terminal : 1 unit
Audio terminal 2ch terminal : 2 unit
5.1ch terminal : 1 unit
Optical terminal : 1 unit
Coaxial terminal : 1 unit
Size 420x65x250 (WxHxD) Module : mm

4
CIRCUIT DIAGRAM
POWER SUPPLY SCHEMATIC DIAGRAM(DQD-6100,220V)

5
CIRCUIT DIAGRAM
VIDEO

6
CIRCUIT DIAGRAM
AUDIO

7
CIRCUIT DIAGRAM
VFD/JOG

8
CIRCUIT DIAGRAM
ETC

9
CIRCUIT DIAGRAM
VCR_INT(DVD)

10
CIRCUIT DIAGRAM
ATAPI(DVD)

11
CIRCUIT DIAGRAM
CPU-ZR36703(DVD)

12
CIRCUIT DIAGRAM
MPEG DECODER

2) Primary rectification and smoothing circuit
AC voltage passed through AC lnlet is rectified to Brige Rectification Diode D801 and changes to
DC voltage. After that it smooths the Smoothing Condenser C806.
When C806 is charged at first, Resistor R802 intercepts voltage current and protects D801, F801.
Start Resistor R803, R804 supply Control IC VCC terminal with rectified DC voltage.
13
1. POWER SUPPLY OPERATION
1) AC input and EMI FILTER
AC inlet consists of Line Filter, X-Cap, Y-Cap, Varister. Line Filter(L801, L802), X-Cap(C803,
C888), Y-Cap(C801) belong to EMI Filter section. They decrease noise to get into and out of AC
Line.
CIRCUIT OPERATIONAL DESCRIPTION
POWER SECTION
Picture 1. [AC Input section]
Picture 2 [Rectification, smoothing and starting circuit]

14
CIRCUIT OPERATIONAL DESCRIPTION
Picture 3 [ Sunbber circuit ]
3) Sunbber circuit
Sunbber circuit protects speedy voltage rising between Collector and Emitter when Main Switching TR is
turned off. So Collector and Emitter voltage enter into safety operation and noise is decreased. When TR
is turnd off, because high reverse voltage is generated between Collector and Emitter, it is rectified to
D802, smoothed to C807 and consumed to R809. C808 is Speed-Up Capacitor.
4) Switching and Control Drive Circuit
When Base of TR is charged through starting part, TR is turned on. So voltage is added to primary
winding of transformer and genertaed at Base Drive. Because this voltage becomes to Positive Feedback
voltage, TR is turned on again and Primary Winding of Trans is charged with electricity .
Picture 4 [Drive Circuit]

15
CIRCUIT OPERATIONAL DESCRIPTION
5) Costant-voltage Circuit
This circuit maintains constant voltage. When voltage is lower or higher than reference voltage(2.5V) of
IC801 pin1, this circuit compensates for a loss. Base voltage of Switching TR is controlled and final
voltage is regulated by increasing or decreasing Internal Diode Current of IC801.
Picture 5 [ Costant-voltage Circuit ]
6) Secondary rectification circuit
This circuit generates DC voltage needed to each terminal. It is rectified half-wave by D821, passes
through Electrolytic Condenser C825 and generates the rectified DC voltage. DC voltage passes
through L821, C822 and is removed of Ripple and Noise. The other terminal operation is same like
this.
Picture 6 [ Secondary rectification circuit ]

16
CIRCUIT OPERATIONAL DESCRIPTION
7) Output terminal
When power is turned off at power applied status, +3.3V is applied to Q822 Base terminal and Q824
MOS FET outputs MVCC(+5V) to Drain terminal. When power is turned on, low signal(0V) is
applied to Q822 Base terminal. At this time, Q824 MOS FET outputs MVCC(+5V) to Drain terminal
and +5V to Source terminal. Q823 funcionates in same process and outputs +12M(Ever +12V) and
+12V.
2. POWER SUPPLY BLOCK DIAGRAM
NOISE
FILTER
SUNBBER
Switching
Primary
rectification
voltage
Control Drive
Circuit
Costant-voltage
Control Drive
Circuit
Starting
Part
Secondery
rectification
voltage
Picture 7 [ Output terminal ]

17
CIRCUIT OPERATIONAL DESCRIPTION
GR7/P7
GR6/P6
GR5/P5
GR4/P4
GR3/P3
GR2/P2
GR1/P1
GR0/P0
VEE
VEE
SCLK
SOUT
SIN
CS
GR8/SEG17 GR9/SEG16 GR10/SEG15 GR11/SEG14 GR12/SEC13 GR13/SEG12 GR14/SEG11 GR15/SEG10 GR16/SEG9 GR17/SEG8 SEG7 SEG6 SEG5 SEG4 SEG3 SEG2 SEG1 SEG0 VCC
AN0 AN1 AN2 AN3 AN4 AN5
RESET OSC1 VSS OSC2 VCC
NOISE FILTER
NOISE FILTER
NOISE FILTER
SERIAL
I/O
MODE
REGISTER DISPLAY CONTROL
CIRCUIT
DISPLAY
MEMORY
TRANSFER
COUNTER
COMMAND ANALYTIC
CIRCUIT BIYE END
TRIGGER
A.D OSCILLATION
CIRCUIT
SELECTOR/A.D
CONTROL CIRCUIT
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11 10 9 8 7 6 5 4 3 2 1
FRONT SECTION
1. VFD DRIVER
1) Overview
IC710 implements following functions by serial communication with MICOM depending on the software.
* CMOS Technology
* Internal Pull-Low Resistance
* 4-step Dimming circuitry
* Output from 8 to 18 Segment
* Output from 7 to 10 Grid
* Built-in Noise filter in Serial clock and serial Input Pins with 2MHz sampling
* 8-bit x 6 channels Analog-to-Digital Converter with +-3LSB Accuracy
2) Input/output port description
* Input: It receives FPSEL, FPCLK and FPDOUT input from MICOM and KEY input by voltage Level.
* Output: It outputs FPDIN with MICOM and operates FLD.
3) Internal BLOCK DIAGRAM

18
CIRCUIT OPERATIONAL DESCRIPTION
2. Front Part Operational Description
1) KEY SCAN & FLD Driver Interface
2) Operation Description
* If user presses KEY while IC500(ZR36705) implements KEY SCAN using VFD DRIVER(PT6355), the
KEY input DATA go to IC500 by SERIAL Communication, then IC500 analyzes and processes the input
DATA.
* Implement the operation according to the input command and display the processing status on the VFD
through PT6355
3) Serial Communication Format

19
CIRCUIT OPERATIONAL DESCRIPTION
AUDIO SECTION
1. 5.1 CH AUDIO DAC IC
1) Overview
24-BIT, 192-kHZ SAMPLING
6-CHANNEL
ENHANCED MULTILEVEL
DELTA-SIGMA DIGITAL-TO-ANALOG CONVERTER
2) Functions
It, as a 5.1CH D/A converter IC, transforms Digital signals to Analog signals by receiving 3 CLOCK
(System CLOCK, Shift CLOCK, Left and Right CLOCK) and 3 DATA from MPEG DECODER.
Each 3 DATA associates to 2 CHANNELS.
->DATA1 : Main L.R CHANNEL
->DATA2 : Surround L.R CHANNEL
->DATA3 : Center, Woofer CHANNEL
During Downmix, it receives only DATA1 from MPEG DECODER.
cf) Downmix : Sound mixing method using 2 CH when the user doesn't have 6 CH amps or speakers but
only have 2 CH.
3) Internal Block Diagram