Sony STR-DB725 User manual

– 1 –
MICROFILM
AEP Model
UK Model
SPECIFICATIONS
SERVICE MANUAL
FM STEREO/FM-AM RECEIVER
STR-DB725/DB825
— Continued on next page —
Photo: STR-DB825

– 13 – – 14 –
STR-DB725/DB825
3-3. SCHEMATIC DIAGRAM – VIDEO INPUT SECTION –
• See page 43 for IC Block Diagrams.
(Page 21)
(Page 32)
(Page 17)
(Page 21)

– 17 – – 18 –
STR-DB725/DB825
3-5. SCHEMATIC DIAGRAM – INPUT SECTION –
• See page 43 for IC Block Diagrams.
(Page 32)
(Page
14)
(Page
37) (Page 31, 32) (Page 33)
(Page
26)
(Page
25)
(Page
37)
(Page 22)
(Page 22)
(Page 21,
22)

– 21 – – 22 –
STR-DB725/DB825
3-7. SCHEMATIC DIAGRAM – S-VIDEO SECTION –
• See page 43 for IC Block Diagrams.
(Page 14) (Page 14) (Page 18) (Page 18)
(Page 18)

– 25 – – 26 –
3-9. SCHEMATIC DIAGRAM – SPEAKER SECTION –
• See page 43 for IC Block Diagrams.
STR-DB725/DB825
(Page 38)
(Page 37)
(Page 37)
(Page 31)
(Page 41)
(Page 38)
(Page 31)
(Page 18)
(Page 18)

– 31 – – 32 –
3-12. SCHEMATIC DIAGRAM – DISPLAY SECTION –
• See page 11 forWaveforms.
• See page 46 for IC Pin Function.
STR-DB725/DB825
(Page
34)
(Page
26)
(Page
38)
(Page
26)
(Page 17,18) (Page 14) (Page 17)
(Page
34)
(Page
34)
(Page
33)

– 33 – – 34 –
3-13. SCHEMATIC DIAGRAM – FRONT PANEL SECTION –
STR-DB725/DB825
(Page 32)
(Page 32)
(Page 32) (Page 31)
(Page 18)

– 37 – – 38 –
3-15. SCHEMATIC DIAGRAM – POWER AMP SECTION –
STR-DB725/DB825
(Page 25)
(Page 41)
(Page 41)
(Page 26)
(Page 31)
(Page 25)
(Page 17)
(Page
18)
(Page 25)

– 41 –
3-17. SCHEMATIC DIAGRAM – TRANS SECTION –
STR-DB725/DB825
(Page 38)
(Page 38)
(Page 26)

– 43 –
3-19. IC BLOCK DIAGRAMS
IC001, 601, 701 uPC2581V
PROTECTOR
DRIVE
12 3 4 5 6 7 8 9 10 11 12 13 14 15
PRE
DRIVE
PRE
DRIVE
BIAS CIRCUIT
REG DRIVE
MUTE
+VOUT1 –VOUT1
COMP1
NF1
IN1
GND
IN2
NF2
COMP2
–VOUT2 +VOUT2
VCC1 VCC2
VEE
IC106 BA6208
1 2 3 4 5 6 7 89
NC
OUTPUT 2
Vcc
GND
NC
INPUT 2
INPUT 1
NC
MOTOR
DRIVE
MOTOR
DRIVE
REG
SWITCH
SWITCH
OUTPUT1
IC251 NJM2296D
9
S5
S6 S7
S4
S1 S2
S3
Vout1
Vout2 Vout3
V-
GND
SW3
SW2SW1
SW5 SW4
Vin1 Vin2
Vin3Vin4Vin5
V+
10111213141516
1 52 3 4 6 7 8
IC302 LC7822
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
CONTROL
LATCH
SHIFT RESISTOR
LEVEL SHIFT
CL
DI
CE
VEE
OUT
IN
OUT
IN
OUT
IN
VSS
S
RESET
VDD
OUT
IN
IN
OUT
IN
OUT
IN

– 44 –
IC400 CXA8081S
IC401 CXA8079S
RB
RB
DC-RS
AGND
DC-OT
NR-R NR-C RS-OUT LS-OUT R-OUT L-OUT
RB
VSS
CLK
DATA
ENABLE
DC-LS
DC-IN
VCC
L-IN
R-IN
S-IN
VREF
FCL-IN
FCR-IN
FCLS-IN
FCRS-IN
OSC
VDD
PDM
PDM-COUT SRA1-8K
20KH-L.P.F.
DEC
5K/7K-L.P.F.
B-NR
R-STEREO
VOL/MUTE
RS-TRIM
LS-TRIM
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
192021222324252627282930313233343536
INV-PHASE
R+DELAY
L+DELAY
-6dB
L+R
L-R
P
B
P
B
20K
20K
20K
20K
48
VCS2 VCS1 VCS-TH L+R-RC
T
L-R-RCT DCUT DCUT R-BPF3 R-BPF2 R-BPF1 CT-OUT2 CT-IN2 MIXOUT C-OUT S-OUT R-OUT L-OUT
VCC
CM-CAP FCC-IN2 ENABLE DATA CLK OSC1
NS-BPF1 NS-BPF2
VREF
S-DCUT C-DCUT
L-DCUT
R-DCUT
V
REF-BUF
L-IN
R-IN
GND
CT-OUT1
CT-IN1
FCC-IN1
L-BRF1 L-BRF2 L-BRF3
DCUT DCUT
R-RCT
VCR-TH
VCR1 VCR2
47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28
L+R-RECT
27 26 25
P. S
VCS-LOG
OSC DEC
N-GEN
N-BPF
N-OH
DIV
BAL-DET
BALCONT
VREF
VR VR
VCRX8
COMB-NET
CMODE SMUTE
C-TRIM
PB
PB
PBPB
R
B
R
B
R-B.P.F.
L-B.P.F.
L-R-RECT
R-RECT
L-RECT VLR-LOG
DUAL-TIME
P. S
24
23
2221
20
19
18
17
16
15
1413121110987654321
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
CONTROL
LATCH
SHIFT RESISTOR
LEVEL SHIFT
CL
D1
CE
VEE
L1
L2
L COM1
L3
L4
L COM2
L5
L6
L COM3
L7
R1
R2
R COM1
R3
R4
R COM2
R5
R6
R COM3
R7
L COM4
VSS
S
RES
VDD
R COM4
IC403 LC7823

– 45 –
IC452 BU1922
QUALITY BIT
GENERATOR
DEFFERENTIAL
DECODER
BIPHASE
SYMBOL
DECODER
OSCILLATOR
AND
DIVIDER
57kHz
BANDPASS
(8th ORDER)
CONTAS LOOP
VARIABLE AND
FIXED DIVIDER
REFERENCE
VOLTAGE
ANTI-
ALIASING
FILTER
CLOCKED
COMPARATOR
TEST LOGIC AND OUTPUT
SELECTOR SWITCH
RECONSTRUCTION
FILTER
141516 13 12 11 10 9
321 4 5 6 7 8
CLOCK REGENERATION
AND SYNC
VP1
RDCL TS7 OSCO OSCI VDDD VSSD TEST TSTL
D
QUAL
RDDA
Vref
MUX
VDDA
VSSA
CIN
SCOUT
IC502 TC9184P
16 15 14 13 12 11 10 9
12 345678
S. DATA
T. LAT +9V
–9V
GND
S. CLK
TONE
CE
BASS + BASS – COM
TREBLE – TREBLE +
BASS + BASS –
COM
TREBLE – TREBLE +
1
2
3
45
6
7
8
V+
VSB/SESIN
VSA
RESET
GND
OUTC
VSC
CR
VREF
+–
–+
–
+
–
+
Q
R S
IC901 NJM2103D