M65KG512AB Datasheet, PDF (14/54 Pages) STMicroelectronics – 512Mbit (4 banks x 8 Mb x 16) 1.8 V supply, DDR low power SDRAM

Commands
M65KG526AB
3.6
Burst Read Terminate command (BST)
The Burst Read Terminate command is used to terminate a Burst Read operation.
It is issued with KE held High, by driving E and W Low and CAS and RAS High. t_BSTZ after
issuing the Burst Read Terminate command, DQ0-DQ15 and LDQS, UDQS revert to the
high impedance state (see Figure 15: Burst Terminate during Read operation).
There is no such command for Burst Write operations.
3.7
Write command (WRIT)
This Write command is used to write to the memory array in Burst Write mode. In this mode,
data is input synchronized with the cross points of the clock signals, K and K.
The start address of the Burst Write is determined by the column address, A0 to A9, and the
address of the selected bank, BA0-BA1, at the beginning of the Burst Read operation. A
valid Write command is initiated by driving E, CAS and W Low, V_IL, and RAS High, V_IH.
3.8
Write with Auto Precharge command (WRITA)
This command is identical to the Write command except that a precharge is automatically
performed at the end of the Write operation. The precharge starts t_WPD (Burst Length/2 +3
clock periods) after the Write with Auto Precharge command is input.
Refer to Figure 19 for a description of Write operation with Auto Precharge.
3.9
Precharge Selected Bank/Precharge All Banks command
(PRE/PALL)
The Precharge Selected Bank and Precharge All Banks are used to place the bank selected
by BA0 and BA1 (see Table 2: Bank selection using BA0-BA1) and all banks in idle mode,
respectively.
The precharge commands are issued by driving E, RAS and W Low, with CAS and KE held
High. The value on A10 determines whether either the selected bank or all the banks will be
precharged:
● If A10 is High, BA0-BA1 are Don’t Care and all the banks are precharged.
● If A10 is Low when, only the bank selected by BA0-BA1 is precharged.
The bank(s) is/are placed in the Idle mode t_RP after issuing the Precharge command. Once
the bank is in Idle mode, the Bank (Row) Activate command has to be issued to switch the
bank back to active mode.
The precharge commands can be issued during Burst Read or Burst Write in which case the
Burst Read or Write operation is terminated and the selected bank placed in Idle mode.
The device needs to be in Idle mode before entering Self Refresh, Auto Refresh, Power-
Down and Deep Power-Down.
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