EDJ1108BABG, EDJ1116BABG
Notes: 1. All DDR3 commands are defined by states of /CS, /RAS, /CAS, /WE and CKE at the rising edge of the
clock. The most significant bit (MSB) of BA, RA, and CA are device density and configuration dependent.
2. /RESET is an active low asynchronous signal that must be driven high during normal operation
3. Bank Addresses (BA) determine which bank is to be operated upon. For MRS, BA selects an mode
register.
4. Burst READs or WRITEs cannot be terminated or interrupted and fixed/on the fly BL will be defined by
MRS.
5. The power-down mode does not perform any refresh operations.
6. The state of ODT does not affect the states described in this table. The ODT function is not available
during self-refresh.
7. Self-refresh exit is asynchronous.
8. VREF (Both VREFDQ and VREFCA) must be maintained during self-refresh operation.
9. The No Operation command (NOP) should be used in cases when the DDR3 SDRAM is in an idle or a
wait state. The purpose of the NOP command is to prevent the DDR3 SDRAM from registering any
unwanted commands between operations. A NOP command will not terminate a previous operation that is
still executing, such as a burst read or write cycle.
10. The DESL command performs the same function as a NOP command.
11. Refer to the CKE Truth Table for more detail with CKE transition.
12. No more than 4 banks may be activated in a rolling tFAW window. Converting to clocks is done by
dividing tFAW (ns) by tCK (ns) and rounding up to next integer value. As an example of the rolling
window, if (tFAW/tCK) rounds up to 10 clocks, and an activate command is issued in clock N, no more
than three further activate commands may be issued in clock N+1 through N+9.
No Operation Command [NOP]
The No Operation command (NOP) should be used in cases when the DDR3 SDRAM is in an idle or a wait state.
The purpose of the NOP command is to prevent the DDR3 SDRAM from registering any unwanted commands
between operations. A NOP command will not terminate a previous operation that is still executing, such as a burst
read or write cycle.
The no operation (NOP) command is used to instruct the selected DDR3 SDRAM to perform a NOP (/CS low, /RAS,
/CAS, /WE high). This prevents unwanted commands from being registered during idle or wait states. Operations
already in progress are not affected.
Device Deselect Command [DESL]
The deselect function (/CS high) prevents new commands from being executed by the DDR3 SDRAM. The DDR3
SDRAM is effectively deselected. Operations already in progress are not affected.
Mode Register Set Command [MR0 to MR3]
The mode registers are loaded via row address inputs. See mode register descriptions in the Programming the
Mode Register section. The mode register set command can only be issued when all banks are idle, and a
subsequent executable command cannot be issued until tMRD is met.
Bank Activate Command [ACT]
This command is used to open (or activate) a row in a particular bank for a subsequent access. The values on the
BA inputs select the bank, and the address provided on row address inputs selects the row. This row remains active
(or open) for accesses until a precharge command is issued to that bank. A precharge command must be issued
before opening a different row in the same bank.
Note: No more than 4 banks may be activated in a rolling tFAW window. Converting to clocks is done by dividing
tFAW (ns) by tCK (ns) and rounding up to next integer value. As an example of the rolling window, if
(tFAW/tCK) rounds up to 10 clocks, and an activate command is issued in clock N, no more than three further
activate commands may be issued in clock N+1 through N+9.
Data Sheet E1248E40 (Ver. 4.0)
67
ELPIDA [ ELPIDA MEMORY ]
