EM638165 Etron Technology Inc., EM638165 Datasheet - Page 13

• Manufacturer Part Number: EM638165
• Description: 4Mega x 16 Synchronous DRAM (SDRAM)
• Manufacturer: Etron Technology Inc.

Preliminary
9
10
CLK
COMMAND
CAS# latency= 2, 3
DQ's
CAS# latency=2
t CK2 , DQ's
CAS# latency=3
t CK3 , DQ's
CLK
COMMAND
Termination of a Burst Write Operation
(RAS# = "H", CAS# = "H", WE# = "H")
is Low). This prevents unwanted commands from being registered during idle or wait states.
Burst Stop command
(RAS# = "H", CAS# = "H", WE# = "L")
command is only effective in a read/write burst without the auto precharge function. The terminated
read burst ends after a delay equal to the CAS# latency (refer to the following figure). The
termination of a write burst is shown in the following figure.
These two bits are used to enter the test mode and must be programmed to "00" in normal
operation.
This bit is used to select the burst write length.
No-Operation command
Termination of a Burst Read Operation
Test Mode field (A8~A7)
Write Burst Length (A9)
The Burst Stop command is used to terminate either fixed-length or full-page bursts. This
The No-Operation command is used to perform a NOP to the SDRAM which is selected (CS#
A8
A9
0
0
1
0
1
READ A
T0
T0
NOP
WRITE A
DIN A 0
T 1
T 1
NOP
A7
X
0
1
Write Burst Length
Single Bit
DIN A 1
DOUT A 0
T2
T2
NOP
NOP
Burst
DIN A 2
DOUT A 0
DOUT A 1
T3
T3
NOP
NOP
Vendor Use Only
Vendor Use Only
normal mode
Test Mode
13
Input data for the Write is masked.
Burst Stop
Burst Stop
don't care
(Burst Length = X, CAS# Latency = 1, 2, 3)
DOUT A 2
(Burst Length ¡ Ö 4, CAS# Latency = 2, 3)
DOUT A 1
T4
T4
DOUT A 2
DOUT A 3
T5
The burst ends after a delay equal to the CAS# latency.
T5
NOP
NOP
DOUT A 3
T6
NOP
T6
NOP
Rev 0.6
EM638165
T7
NOP
T7
NOP
Feb. 2001
NOP
T8
NOP
T8