Platinenabbildungen und Schaltpläne / Layout of PCBs and Circuit Diagrams
GDV 100 D
k
4 - 44
GRUNDIG Service
With the following commands, the Audio deemphasis and Audio mute
can be checked.
Ref. #
Command
Remark
Testpoint
Level
30a
AudioDeemp0On Audio-Deemphasis 0 On
1400-(3)
>4.5V
30b
AudioDeemp0Off Audio-Deemphasis 0 Off
1400-(3)
<0.2V
30a
AudioDeemp1On Audio-Deemphasis 1 On
1400-(4)
>4.5V
30b
AudioDeemp1Off Audio-Deemphasis 1 Off
1400-(4)
<0.2V
31a
AudioMuteOn
Audio-Mute On
1400-(11)
>4.5V
31b
AudioMuteOff
Audio-Mute Off
1400-(11)
<-4.0V
With the following commands we test if the S2B communication with
the B.E .-Emulator is O.K. and then via the second test the Digital Board
will operate in CDDA transparent mode.
Ref. #
Command
Remark
20
PapS2bEcho
S2B Echo
28
AudioSig
Audio Signatur
4. LSI-MPEG-Decoder IC7303
Check operating voltages: >3.0V
– IC7303 (VDD1…13, AVCD)
– DRAMs IC7302, IC7304…IC7306 (VCC1…3)
Check ground connections: <0.2V
– IC7303 (GND1…15, GNDA)
– DRAMs IC7302, IC7304…IC7306 (GND1…3)
With the following commands the LSI-MPEG-Decoder can be checked:
Ref. #
Command
Remark
63
CompLsiAcc
LSI accesible
65
CompLsiDramAcc
LSI DRAM’s accesible
25
CompLsiDramWrR
LSI DRAM Write Read
5. DVP IC7201
The DVP is located in the same chip as the DSM. This means that the
communication has already been checked.
Check operating voltages VCC1/2 of IC7202 (FIFO): >4.7V
Check ground connections VSS1/2 of IC7202 (FIFO): <0.2V
With the following command the connection to FIFO can be checked:
Ref. #
Command
Remark
23
CompDvpFifoSig
DVP FIFO Signatur
6. Video
6.1 Video Encoder IC7406
For the next test, the A/V-MUX Board must be connected to the Digital
Board.
Check operating voltages VDD, VAA1…3 of IC7406: >4.75V
Check ground connections GND1…3, GNDA1…7 of IC7406: <0.2V
Check following signals:
Signal
Testpoint
Level
Y0…Y7
IC7406-(16…25)
<0.2V
Blank
IC7406-(48)
>4.75V
Slave
IC7406-(42)
>4.75V
Altador
IC7406-(26)
<0.2V
Sleep
IC7406-(39)
<0.2V
RGBout
IC7406-(14)
<0.2V
For a correct adjustment of analog video, check the value of R3400 :
150
Ω
. Check VREF of IC7406-(3): 1.355V
±
5%
Generate a colourbar via next software commands:
Ref. #
Command
Remark
36a
VideoColDencOn
Colourbar DENC On
36b
VideoColDencOff
Colourbar DENC Off
Check RGB- and CVBS-voltages at following testpoints:
– CVBS:
1400-(17)
– R:
1400-(18)
– G:
1400-(20)
– B:
1400-(21)
6.2 Video Path
To check a large part of the video-path (DSM-LSI-DVP-Denc) a
colorbar can be generated via next commands:
Ref. #
Command
Remark
37a
VideoColDsmOn
Colourbar DSM On
37b
VideoColDsmOff
Colourbar DSM Off
To check the videopath with the commands 32…33 a B.E.-Emulator
must be conected to the I2S input.
Ref. #
Command
Remark
32a
VideoSigFullOn
Signatur Full On
32b
VideoSigFullOff
Signatur Full Off
33
VideoSigFullChk
Signatur Full Check
67a
VideoSigLsiOn
Signatur LSI On
67b
VideoSigLsiOff
Signatur LSI Off
With Signature Full On(32a), the following can be measured on the
EURO-AV socket:
Signal
EURO-AV contact
Level
CVBS burst
19
300mV
PP
±
15%
CVBS sync
19
300mV
PP
±
15%
CVBS white level
19
700mV
PP
±
15%
CVBS chroma
19
450mV
PP
±
15%
EURO-AV – blue
7
900mV
pp
±
15%
EURO-AV – green
11
900mV
PP
±
15%
EURO-AV – red
15
900mV
PP
±
15%
The scart-switching voltage can be 0V, 6V, 12V.
Check at connector 1400-(15) the output-voltage while using next
commands:
Ref. #
Command
Remark
57a
VideoScartLo
Output Level 0V
±
10%
57b
VideoScartMi
Output Level 6V
±
10%
57c
VideoScartHi
Output Level 12V
±
10%
