
W981216AH
2M x 16 bit x 4 Banks SDRAM
Revision 1.0 Publication Release Date: March, 1999
- 3 -
Pin Assignment
Pin Number
23 ~ 26, 22,
29 ~35
20, 21
Pin Name
A0~ A11
Function
Address
Description
Multiplexed pins for row and column address.
Row address : A0 ~ A11. Column address: A0 ~ A8.
Select bank to activate during row address latch time, or bank to
read/write during address latch time.
Multiplexed pins for data output and input.
BS0, BS1
Bank Select
2, 4, 5, 7, 8,
10, 11, 13,
42, 44, 45,
47, 48, 50,
51, 53
19
DQ0 ~
DQ15
Data Input/
Output
CS#
Chip Select
Disable or enable the command decoder. When command
decoder is disabled, new command is ignored and previous
operation continues.
Command input. When sampled at the rising edge of the clock,
RAS#, CAS# and WE# define the operation to be executed.
Referred to RAS#
18
RAS#
Row Address
Strobe
Column
Address Strobe
Write Enable
input/output
mask
17
CAS#
16
39, 15
WE#
UDQM/
LDQM
Referred to RAS#
The output buffer is placed at Hi-Z(with latency of 2) when DQM
is sampled high in read cycle. In write cycle, sampling DQM
high will block the write operation with zero latency.
System clock used to sample inputs on the rising edge of clock.
CKE controls the clock activation and deactivation. When CKE
is low, Power Down mode, Suspend mode, or Self Refresh
mode is entered.
Power for input buffers and logic circuit inside DRAM.
Ground for input buffers and logic circuit inside DRAM.
Separated power from V
CC
, used for output buffers to improve
noise.
Separated ground from V
SS
, used for output buffers to improve
noise.
No connection
38
37
CLK
CKE
Clock Inputs
Clock Enable
1, 14, 27
28, 41, 54
3, 9, 43, 49
V
CC
V
SS
V
CC
Q
Power ( +3.3 V )
Ground
Power ( + 3.3 V
) for I/O buffer
Ground for I/O
buffer
No Connection
6, 12, 46, 52
V
SS
Q
36, 40
NC