23

Rev. 0A | October 2022

www.issi.com - dram@issi.com

IS43/46LR32320C

IS43/46LR16640C

Note:

1. The table applies when both CKE

n-1 and CKEn are HIGH, and after tXSR or tXP has been met if the previous state was Self Refresh or

Power Down.

2. DESELECT and NOP are functionally interchangeable.

3. All states and sequences not shown are illegal or reserved.

4. Current State Definitions:

Idle: The bank has been precharged, and tRP has been met.

Row Active: A row in the bank has been activated, and tRCD has been met. No data bursts/accesses and no register accesses are in

progress.

Read: A READ burst has been initiated, with AUTO PRECHARGE disabled, and has not yet terminated or been terminated.

Write: a WRITE burst has been initiated, with AUTO PRECHARGE disabled, and has not yet terminated or been terminated.

5. Read with AP enabled and Write with AP enabled: The read with Autoprecharge enabled or Write with Autoprecharge enabled states

can be broken into two parts: the access period and the precharge period. For Read with AP, the precharge period is defined as if the

same burst was executed with Auto Precharge disabled and then followed with the earliest possible PRECHARGE command that still

accesses all the data in the burst.

For Write with Auto precharge, the precharge period begins when tWR ends, with tWR measured as if Auto Precharge was disabled.

The access period starts with registration of the command and ends where the precharge period (or tRP) begins.

During the precharge period, of the Read with Autoprecharge enabled or Write with Autoprecharge enabled states, ACTIVE,

PRECHARGE, READ, and WRITE commands to the other bank may be applied; during the access period, only ACTIVE and PRECHARGE

commands to the other banks may be applied. In either case, all other related limitations apply

(e.g. contention between READ data and WRITE data must be avoided).

6. AUTO REFRESH, SELF REFRESH, and MODE REGISTER SET commands may only be issued when all bank are idle.

7. A BURST TERMINATE command cannot be issued to another bank;

It applies to the bank represented by the current state only.

8. READs or WRITEs listed in the Command column include READs and WRITEs with AUTO PRECHARGE enabled and READs and WRITEs

with AUTO PRECHARGE disabled.

9. Requires appropriate DM masking.

10. A WRITE command may be applied after the completion of data output, otherwise a BURST TERMINATE command must be issued to

end the READ prior to asserting a WRITE command.