BBK SP550S Service Manual

ENGLISH

SP550S

Service manual

CAUTIONS

SP550S SERVICE MANUAL

There is high voltage inside this unit. Make sure to pull out the plug of this unit before repairing! There are many high voltage components inside this unit. Please pay attention to all warnings and instructions marked on this unit to avoid electric shock! Specifications of the replaced components must be the same as that of the original components. Do not change the components' specifications to prevent risks!

CONTENTS

Contents

CAUTIONS

1 SP550S FEATURES

2 CIRCUIT CONNECTION DIAGRAM & BLOCK DIAGRAM

3 DETAILED CIRCUIT EXPLANATIONS

10 THE EXPLANATION FOR KEY COMPONENTS

VOLUME CONTROL IC PT2258 CPU IC AT89C2051 POWER IC TDA7370B POWER IC TDA2003 POWER IC LM1875

SP550S SERVICE MANUAL

SP550S FEATURES

5.1CH volume and level adjustment incorporate IC PT2258 and realize the standby and mute functions. CPU incorporates IC AT89C2051. Small signal amplification and amplified LPF incorporate IC NJM4558. Power amplification of L, R, SL and SR channels incorporates power IC TDA7370B. Power amplification of the C channel employs power IC TDA2003. Power amplification of the SW channel employs two LM1875 to form BTL. Status display employs a LED digital tube, displayed range: 0~16. Full function remote control. Square power transformer, bridge and full wave rectifying circuit. Satellite speakers employ plastic body. Subwoofer speaker's body employs xyloid MDF construction with PVC cover. Satellite speakers employ 3-foot wide frequency band high performance unit. Subwoofer incorporates 8-foot aluminum audio coil with dual magnetic circuits exclusively for the subwoofer unit. All-in-one flat radiator board with long radiator sluts for excellent heat radiation.

SP550S SERVICE MANUAL

CIRCUIT CONNECTION DIAGRAM & BLOCK DIAGRAM

CIRCUIT CONNECTION DIAGRAM

INPUT BOARD

XP2

BLOCK DIAGRAM

INPUT BOARD

1. 1. SR

2. 2. SL

4. 4.

R L

GND

~14V

1. 0 ~14V

Transformer

SW SR SL

C R

1.1.

2.2.

GND

3.3.

5.1CH

INPUT

XS1

POWER AMPLIFYING BOARD

XS2

XS3

VsRMb1+c1b2a2

c2c26. 6.d2e2f2GND

1.1.2.2.2.

3.3.3.4.4.

7.7.

8.8.

VsRMb1+c1b2a2

FRONT PANEL'S BOARD

MAIN POWER AMPLIFYING BOARD

LL R SL SR

VOLUME CONTROL

L R

5. 5.

XP3

d2e2f2

9.9.

10.10.

GND

11. 11.

LPF

AMPLIFICATION

GND

1. 1. GND

2. 2. C

3. SR

4. 4.

XS4

L R SL

SW SPEAKER

L R SL SR

POWER AMPLIFICATION

BUFFER

AMPLIFICATION

POWER AMPLIFICATION

GND GND C

3. SR

XP4

1.1. R

2.2. SL

3.3.

OUTPUT BOARD

POWER AMPLIFICATION

OUTPUT BOARD

CPU

REMOTE CONTROL RECEPTION

FRONT PANEL'S CONTROL BOARD

LED

DISPLAY

POWER SUPPLY

NO LOCATION SP ECIFICATI ONS DESCRIP TIO N SPECIFICATIONS / PART NUMBER

1 R405 Carbon-film Resistor 1/6W680

¦¸

±5% SHAPED 7.5 2 R406~R412,R451,R455,R470 Carbon-film Resistor 1/6W1.5K±5% SHAPED 7.5 3 R415,R419,R421,R424,R425,R428 Carbon-film Resistor 1/6W4.7K±5% SHAPED 7.5 4 R404,R434,R437,R440,R443,R466 Carbon-film Resistor 1/6W10K±5% SHAPED 7.5 5 R435,R438 Carbon-film Resistor 1/6W12K ±5% SHAPED 7.5

R450,R458,R452,R454,R456,R416,R418, R422,R423, R426,R427,R441,R444,R459,R465

Carbon-film Resistor 1/6W22K±5% SHAPED 7.5

7 R446,R467 Carbon-film Resistor 1/6W47K±5% SHAPED 7.5

R432,R433,R439,R442,R447,R448,R464, R445,R436

Carbon-film Resistor 1/6W100K±5% SHAPED 7.5

9 R417,R420,R429~R431 Carbon-film Resistor 1/6W150K±5% SHAPED 7.5

10 R413,R414,R453,R457,R463 Carbon-film Resistor 1/4W10

¦¸

±5% SHAPED 10

11 R462 Carbon-film Resistor 1/6W2.2

¦¸

±5% SHAPED 7.5

12 R401,R402 Carbon-film Resistor 1/2W220

¦¸

±5% SHAPED 12.5

13 R449 Carbon-film Resistor 1/6W220

¦¸

±5% SHAPED 7.5

15 R460 Carbon-film Resistor 1/6W47

¦¸

±5% SHAPED 7.5

16 R403 Carbon-film Resistor 1/4W180

¦¸

±5% SHAPED 10

17 R461 Carbon-film Resistor 1W220

¦¸±5£¥

18 C459 Porc el ain Capaci tor 50V 33P ±10% NPO 2.5mm 19 C462,C428,C430,C460,C461 Porc el ain Capaci tor 50V 151 ±10% 2.5mm 20 C417,C418 Porcel ain Capaci tor 50V 20P ±10% NPO 2.5mm

C405,C406,C409,C410,C413,C416,C456, C458

Porc el ain Capaci tor 50V 104 ±10% 5mm

22 C424,C436 Terylene Capacitor 100V 103 ±10% 3.5mm 23 C440,C442,C445 Terylene Capacitor 100V 104 ±10% 7mm 24 C401,C402 Terylene Capacitor 100V 224 ±10% 8mm 25 C425,C437 Terylene Capacitor 100V 182 ±5% 3.5mm

26 C447~C450

Metal Polyester Film Capacitor

CL21X 100V224±10% 7.5

27 C415,C432,C457 CD CD11 16V10U±20%5×11 2 28 C414,C451 CD CD11 16V47U±20%5×11 2 29 C412 CD CD11 16V220U±20%6×12 2.5 30 C407,C408,C444 CD CD11 16V470U±20%8×123.5 31 C439,C441 CD CD11 25V22U±20%5×11 2

C419~C423,C426,C427,C429,C431,C433, C434,C435,C438,C443

CD CD11 50V2.2U±20%5×11 2

33 C403,C404,C411 CD CD11 25V4700U±20%16×35 7.5 34 C446,C452~C455 CD CD11 25V220U±20%8×12 3.5 35 VD412,VD413 Diode 1N4004 36 VD401~VD406 Diode RL254 37 VD41 1 Voltag e Regul ator Di ode 5.1V 1/2W 38 VD409,VD410 Voltag e Regul ator Di ode 12V 1/2W

39 N402

Software Program CPU , AT89C2051 DIP

CPUHT60(EN)-0

40 N404~N406 IC 4558C DIP

SP550S SERVICE MANUAL

DETAILED CIRCUIT EXPLANATIONS

1. THE POWER AMPLIFYING BOARD

MAIN PARTS LIST OF THE MAIN POWER AMPLIFYING BOARD

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