w9425g6dh Winbond Electronics Corp America, w9425g6dh Datasheet - Page 7

• Manufacturer Part Number: w9425g6dh
• Description: 4m X 4 Banks X 16 Bits Ddr Sdram
• Manufacturer: Winbond Electronics Corp America

5. PIN DESCRIPTION
11, 13, 54, 56, 57,
59, 60, 62, 63, 65
6, 12, 52, 58, 64
2, 4, 5, 7, 8, 10,
PIN NUMBER
3, 9, 15, 55, 61
14, 17, 19, 25,
23, 22, 21
34, 48, 66
43, 50, 53
1, 18, 33
28 − 32,
35 − 42
26, 27
20, 47
45, 46
16,51
24
44
49
LDM, UDM
CAS , WE
BS0, BS1
A0 − A12
NAME
LDQS,
DQ0 −
UDQS
DQ15
V
V
RAS ,
CLK,
V
CKE
CLK
V
PIN
V
NC
CS
DDQ
SSQ
REF
DD
SS
Reference Voltage V
Data Input/ Output
Power (+2.5V) for
Command Inputs
Differential Clock
No Connection
Power (+2.5V)
Ground for I/O
Clock Enable
FUNCTION
Bank Select
Data Strobe
Chip Select
Write Mask
I/O Buffer
Address
Ground
Inputs
Buffer
Select bank to activate during row address latch time, or
bank to read/write during column address latch time.
Disable or enable the command decoder. When command
decoder is disabled, new command is ignored and previous
operation continues.
When DM is asserted “high” in burst write, the input data is
masked. DM is synchronized with both edges of DQS.
All address and control input signals are sampled on the
crossing of the positive edge of CLK and negative edge of
Power for logic circuit inside DDR SDRAM.
Separated ground from V
Multiplexed pins for row and column address.
Row address: A0 − A12.
Column address: A0 − A8. (A10 is used for Auto-precharge)
The DQ0 – DQ15 input and output data are synchronized
with both edges of DQS.
DQS is Bi-directional signal. DQS is input signal during write
operation and output signal during read operation. It is Edge-
aligned with read data, Center-aligned with write data.
Command inputs (along with
being entered.
CKE controls the clock activation and deactivation. When
CKE is low, Power Down mode, Suspend mode, or Self
Refresh mode is entered.
Ground for logic circuit inside DDR SDRAM.
Separated power from V
improve noise.
improve noise.
No connection
floating)
CLK
REF
- 7 -
.
is reference voltage for inputs.
(NC pin should be connected to GND or
Publication Release Date:Feb. 12, 2008
DESCRIPTION
DD
SS
, used for output buffer, to
, used for output buffer, to
CS
) define the command
W9425G6DH
Revision A8