JVC RC-BM5 Service Manual page 27

AS4C256KEO (IC701) : DRAM
1. Termianl layout
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
3. Pin function
Pin No. Symbol
1 VCC
2 to 5 I/O0 to I/O3
6 Vcc
7 to 10 I/O4 to I/O7
11,12 NC
13 WE
14 RAS
15 NC
16 to 19 A0 to A3
20 Vcc
21 GND
22 to 26 A4 to A8
27 OE
28 UCAS
29 LCAS
30 NC
31 to 34 I/O8 to I/O11
35 GND
36 to 39 I/O12 to I/O15
40 GND
2. Block diagram
WE
40
RAS CONTROL
39
CASL LOGIC
38
CASH
37
36
35
34
33
32
CLOCK
31
GENERATOR
30
29
28
27
COLUMN
26
25
ADDRESS
24
BUFFER
23
A0
22
21
A1
REFRESH
A2
CONTROLER
A3
A4
A5
REFRESH
A6
COUNTER
A7
A8
ROW.
ADDRESS
BUFFERS<9>
I/O
- Power (5V 0.5V)
I/O Input/output
- Power (5V 0.5V)
I/O Input/output
- Not connect
- Read/write control
- Row address strobe
- Not connect
I Address inputs
- Power (5V 0.5V)
- Ground
I Address inputs
O Output enable
- Column address strobe,upper byte
- Column address strobe,lower byte
- Not connect
I/O Input/output
- Ground
I/O Input/output
- Ground
DATA-IN
BUFFER
COLUMN
DECODER
512
SENSE AMPLIFIERS
I/O GATING
512 X 16
512 x 512 x 16
512
MEMORY
ARRAY
V
BB
GENERATOR
Function
RC-BM5
IO0
.
IO15
DATA-OUT
BUFFER
OE
V
CC
V
SS
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