Sony BM-21 Service Manual page 44

BM-21/23
• IC Block Diagrams
— AUDIO Board —
IC102, IC103 MM3111AWLE
SHUTDOWN
1
BIAS
BYPASS 2
+IN 3
-IN 4
IC502 MM1210-XFF
VCC
ROUT1 OP1
1
CO3
VCC
ROUT2 OP2
2
CO4
TC 3
ADJ 4
BM-21/23
8 VO2
7 GND
6 VDD
5
VO1
8 VCC
CO1
7 CF
CO3
6 RIPPLE
5 GND
IC601 LB1979VS-TLM-E
20 19 18
VCC
VCC
18 18
17 16 15 14 13 12
SPEED CONTROL STARTING
REFERENCE VOLTAGE DETECT
WAVEFORM DETECT
COMMUTATION STARTING LOGIC
SPEED CURRENT
DETECT DETECT
SOFT SWITCH
PRE DRIVER
TO
EACH
BLOCKS
1 2 3 4 5 6 7 8 9
11
OSCILLATING
CIRCUIT
POWER
SUPPLY
BIAS
REFERENCE
VOLTAGE
TO
CONTROL
BLOCKS
10