EM636327Q-7 Etron Technology Inc., EM636327Q-7 Datasheet - Page 9

• Manufacturer Part Number: EM636327Q-7
• Description: 512K x 32 High Speed Synchronous Graphics DRAM(SGRAM)
• Manufacturer: Etron Technology Inc.

Preliminary
6
7
CLK
COM MAND
DQ0 - DQ3
CLK
ADDRESS
COM M AND
CAS# latency=1
t CK1 , DQ's
CAS# latency=2
t CK2 , DQ's
CAS# latency=3
t CK3 , DQ's
Read and AutoPrecharge command
(RAS# = "H", CAS# = "L", WE# = "H", DSF = "L", BS = Bank, A9 = "H", A0-A7 = Column Address)
the read operation. Once this command is given, any subsequent command cannot occur within a
time delay of {t
this command and the auto precharge function is ignored.
Write command
(RAS# = "H", CAS# = "L", WE# = "L", DSF = "L", BS = Bank, A9 = "L", A0-A7 = Column Address)
row in an active bank. The bank must be active for at least t
issued. During write bursts, the first valid data-in element will be registered coincident with the Write
command. Subsequent data elements will be registered on each successive positive clock edge
(refer to the following figure). The DQs remain with high-impedance at the end of the burst unless
another command is initiated. The burst length and burst sequence are determined by the mode
register, which is already programmed. A full-page burst will continue until terminated (at the end of
the page it will wrap to column 0 and continue).
command is a masked write (Write-Per-Bit). Data is written to the 32 cells (bits) at the selected
column location subject to the data stored in the Mask register. The overall mask consists of the
DQM inputs, which mask on a per-byte basis, and the Mask register, which masks also on a per-bit
basis. This is shown in the following block diagram.
The Read and AutoPrecharge command automatically performs the precharge operation after
The Write command is used to write a burst of data on consecutive clock cycles from an active
Any Write performed to a row that was opened via an BankActivate & Masked Write Enable
The first data element and the write
are registered on the same clock edge.
READ A
Col A
T0
Bank,
T0
Burst Write Operation
NOP
RP
(min.) + burst length}. At full-page burst, only the read operation is performed in
WRITE A
DIN A 0
T 1
DOUT A 0
T 1
NOP
Read to Precharge
DIN A 1
DOUT A 0
T2
NOP
T2
DOUT A 1
NOP
(Burst Length = 4, CAS# Latency = 1, 2, 3)
DIN A 2
DOUT A 2
DOUT A 0
T3
T3
NOP
DOUT A 1
NOP
9
(CAS# Latency = 1, 2, 3)
DIN A 3
Precharge
Bank(s)
DOUT A 2
T4
NOP
T4
DOUT A 3
DOUT A 1
Extra data is masked.
don't care
RCD
DOUT A 2
T5
T5
NOP
DOUT A 3
NOP
(min.) before the Write command is
t
RP
T6
NOP
DOUT A 3
T6
NOP
EM636327
Activate
NOP
T7
T7
Bank,
Row
December
NOP
T8
NOP
T8
1998