M5M4V64S20ATP-8, -10, -12
64M (4-BANK x 4194304-WORD x 4-BIT) Synchronous DRAM
The M5M4V64S20ATP provides basic functions, bank (row) activate, burst read / write, bank (row)
precharge, and auto / self refresh.
Each command is defined by control signals of /RAS, /CAS and /WE at CLK rising edge. In addition to 3
signals, /CS ,CKE and A10 are used as chip select, refresh option, and precharge option, respectively.
To know the detailed definition of commands, please see the command truth table.
Chip Select : L=select, H=deselect
Refresh Option @refresh command
Precharge Option @precharge or read/write command
define basic commands
Activate (ACT) [/RAS =L, /CAS =/WE =H]
ACT command activates a row in an idle bank indicated by BA.
Read (READ) [/RAS =H, /CAS =L, /WE =H]
READ command starts burst read from the active bank indicated by BA. First output data appears after
/CAS latency. When A10 =H at this command, the bank is deactivated after the burst read (auto-precharge,
Write (WRITE) [/RAS =H, /CAS =/WE =L]
WRITE command starts burst write to the active bank indicated by BA. Total data length to be written is
set by burst length. When A10 =H at this command, the bank is deactivated after the burst write (auto-
Precharge (PRE) [/RAS =L, /CAS =H, /WE =L]
PRE command deactivates the active bank indicated by BA. This command also terminates burst read /
write operation. When A10 =H at this command, both banks are deactivated (precharge all, PREA).
Auto-Refresh (REFA) [/RAS =/CAS =L, /WE =CKE =H]
REFA command starts auto-refresh cycle. Refresh address including bank address are generated inter-
nally. After this command, the banks are precharged automatically.