Yamaha GX-505 Service Manual page 54

A B
GX-505/GX-505VCD
SCHEMATIC DIAGRAM (GX-505VCD OPERATION)
1
P65 G-2
2
-11.8
0 4 5
0
3
0 2
0 7
8 0
6
1
0
BUFFER 12.0
12.0
1 4 0
2
0 3 0
3
7 0
0 8
6 0
5
-11.8
MIC MIXING
4
DIGITAL ECHO
5
6
7
IC800 : M65853FP
Mic Amp with Digital Echo
42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22
VCC GND
LPF D/A
PHASE
µ–COM I/F SHIFTER
SURROUND
(L+R)/2 L R STEREO
MIC SW
8
ECHO ECHO 16kbit
VOL F.BVOL SRAM
MAIN LOGIC
MIC
MIC
MCLK VOL LPF A/D 1/2Vcc
VOL
ALC ALC
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
67
C D E
MUTING
0
-6.1
0
0
-6.1
0
YMERSION
P65
G-9
4.9
4.9
0
IC804 : YSS247-D
YMERSION
11 8 3 2 1 24 23 22
AVDD
14
FILTER SWITCH
+1
VREF 17 VREF
–1 +1
SWITCH SWITCH
YMERSION TONE CONTROL
TO SWITCHES
SWITCH –1 SWITCH +1
SW 13
+1
COMPARATORS
FILTER SWITCH
AVSS 15
12 10 7 6 5 20 19 18
F G
P65
H-2
12.3
4.9
0
12.9
0 3 1
2
0 4 0
0 6
8
0 7 0
5
-11.9
BUFFER
4.8
4.9
0.9
0
0
0.6
LED DRIVER
IC802 : BU2092
Serial In/Parallel Out Driver
VSS 1 18 VDD
DATA 2 17 OE
CONTROL
CLOCK 3 16 Q11
CIRCUIT
LCK 4 Q10
15
Q0 5 14 Q9
µ
IC805~807 : PC4570HA
Q1 6 13 Q8
Dual OP-Amp
Q2 12 Q7
7
Q3 8 11 Q6
Q4 9 10 Q5
1
– +
1 2 3 4
V CC V O1 –Vm 1 +Vm
H I
-27.4
-22.0
P65
H-9
IC803 : M66004MASP
FL Driver
DISPLAY CODE
CS 14 SERIAL
REGISTER CGROM
SCK 15 RECEIVE 59 SEG00
(8BITx16) (35BITx160)
SDATA CIRCUIT
16
CODE SEGMENT 33 SEG26
WRITE OUTPUT
31 SEG27
CIRCUIT
CGRAM SEG35
23
(35BITx16)
CORD/
COMMAND
RAM
CONTROL
WRITE
CIRCUIT
18 P0
OUTPUT
PORT
(2BIT)
17 P1
DISPLAY
CONTROL
RESET 13
REGISTER CODE
SELECT
12 DIG00
2 XIN 21
CLOCK DISPLAY DIGITAL
1 DIG11
+ – GENERATOR CONTROLLER OUTPUT
XOUT 20 64 DIG12
CIRCUIT
5 6 7 8 9
61 DIG15
1 V EE +Vm 2 –Vm 2 V O2 V CC
J K L
FL
DRIVER
* All voltage are measured with a 10M Ω /V DC electric volt meter.
* Components having special characteristics are marked Z and
must be replaced with parts having specifications equal to those
originally installed.
* Schematic diagram is subject to change without notice.