Sony SCD-XB940, Service Manual

Page: 34 / 73

34
• IC Block Diagrams
– MAIN Board –
IC621 SN74LV74APWR
IC628 MSM54V16258BSL-40TS-K
14
1 2 3 4 5 6 7
13 12 11 10 9 8
VCC
GND
CK
CLR
CK
CLR
Q
PR
Q
Q
PR
Q
D
D
NC
A8 A7 A6 A5 A4 VSS
A0 A1 A2 A3
VCC VCC DQ0 DQ1 DQ2 DQ3 VCC DQ4 DQ5 DQ6 DQ7
WE
RAS
NC
28 26 27 23 24 25
18 20 19 22 21 2 1 4 3 6 5 8 7 10 9
VSS DQ15 DQ14 DQ13 DQ12 VSS DQ11 DQ10 DQ9 DQ8
43 44 41 42 39 40 37 38 35 36 31
I/O
SELECTOR
OUTPUT
BUFFER
INPUT
BUFFER
OUTPUT
BUFFER
INPUT
BUFFER
SENSE
AMPLIFIER
COLUMN
DECODERS
MEMORY
CELLS
WORD
DRIVERS
ROW
DECODERS
COLUMN
ADDRESS
BUFFERS
LCAS
30
UCAS
29
OE
I/O
CONTROLLER
I/O
CONTROLLER
15 16 17
11 – 14
NC
34 – 32
ROW
ADDRESS
BUFFERS
INTERNAL
ADDRESS
COUNTER
REFRESH
CONTROL
CLOCK
TIMING
GENERATOR