Boss Dr. Rhytm DR-550 MK II Service Notes page 11

APRIL.1992
DR-550mk2
ICDATA/ICx-^ MB1
-*Main Board (1/2) (pcb
2292586803
1/2)
MB2-*Main
Board (2/2) (pcb
2292586803
2/2)
MASK CPU
(IC1
on
MB1)
U
PD7531 6GF- 237- 3B9
(15199803)
64
41
65
80
40
iiiiiiiiiiiiiii(nnnn
1
24
(TOP VIEW)
F— 25
1
S12 21
COMO
41 P03 61 P61
2 SI 3 22
COM1 42 P10 62 P62
3
S14 23
COM2
43 P11 63
P63
4 SI 5 24
COM3 44 P12 64 P70
5 SI 6
25 BIAS 45 PI 3 65 P71
6 SI 7 26
VLCO 46 P20 66 P72
7 SI 8
27 VLC1 47 P21 67
P73
8 S19 28
VLC2 48 P22 68 RESET
9 S20
29 P40 49 P23 69
SO
10 S21 30 P41
50 P30 70 SI
11
S22
31
P42 51 P31 71
S2
12 S23 32
P43 52 P32 72 S3
13 S24 33 VSS 53
P33 73 S4
14 S25
34 P50 54
VDD
74 S5
15 S26 35 P51
55 XT1 75 S6
16
S27 36 P52 56
XT2 76
S7
17 S28
37 P53 57
N.C.
77 S8
18 S29 38 POO 58 XI
78 S9
19 S30
39 SCK 59 X2 79 S10
20 S31
40 SBO 60 P60 80
,111
Gate Array (IC2
on
MB2)
MB87604PF-G-BND
(15239138)
(TOP VIEW)
2
INPUT
NAND
GATE
(IC4
on
MB1)
TC7S00F
(15259883)
5
VDD
4
OUT X
PHOTO COUPLER
(IC7
on
MB1)
PC- 400 (OPTO- ISOLATOR)
(15289124)
2
CATHODE
ANODE
(TOP VIEW)
D/A
Converter
p
PD6376GS
(15289701)
(IC103 on
MB2)
+ 5V
Voltage
LM2931 Z-5.0
(15199216)
Regulator
(IC1
01 on
MB2) + 3V
Voltage Regulator (IC102 on
MB2)
SCI771
OYDA
(15289401)
TRANSISTOR (Q1 -3 on
MB1)
(Q101 on
MB2)
2SC2412KR (NPN
type)
(15319101)
fs
SEL
E
E
CLK
D.GND
E E
SI
NC
E E
LRSEL/SI
D.VDD
E
LRCK
A.GND
E
1
A.GND
ROUT
E
E
LOUT
A.VDD
E
E
L.REF
A.
VDD
E
E
.
R.REF
1
OUT
2
GND
3
IN
1
2 3
a
7j
U
1
Emitter
2 Base
3
Collector
(FRONT VIEW)
(TOP VIEW)
(TOP VIEW)
(TOP VIEW)
11