HYB18H512321BF Datasheet, PDF(9/43 Page) Qimonda AG

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HYB18H512321BF Datasheet, PDF (9/43 Pages) Qimonda AG – 512-Mbit GDDR3 Graphics RAM

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Internet Data Sheet

2.3

Truth Tables

HYB18H512321BF

512-Mbit GDDR3

2.3.1

Function Truth Table for more than one Activated Bank

If there is more than one bank activated in the Graphics SDRAM, some commands can be performed in parallel due to the

chipâs multibank architecture. The following table defines for which commands such a scheme is possible. All other transitions

are illegal. Notes 1-11 define the start and end of the actions belonging to a submitted command. This table is based on the

assumption that there are no other actions ongoing on bank n or bank m. If there are any actions ongoing on a third bank tRRD,

tRTW and tWTR have to be taken always into account.

TABLE 4

Function Truth Table I

Current State

Ongoing action on bank n

Possible action in parallel on bank m

ACTIVE

ACTIVATE1)

WRITE3)

WRITE/A5)

READ7)

READ/A9)

PRECHARGE10)

PRECHARGE ALL 10)

POWER DOWN ENTRY12)

ACT, PRE, WRITE, WRITE/A, READ, READ/A2)

ACT, PRE, WRITE, WRITE/A, READ, READ/A4)

ACT, PRE, WRITE, WRITE/A, READ6)

ACT, PRE, WRITE, WRITE/A, READ, READ/A8)

ACT, PRE, WRITE, WRITE/A, READ, READ/A 8)

ACT, PRE, WRITE, WRITE/A, READ, READ/A11)

IDLE

ACTIVATE 1)

ACT

POWER DOWN ENTRY 12)

AUTO REFRESH13)

SELF REFRESH ENTRY 12)

MODE REGISTER SET (MRS)14)

EXTENDED MRS 14)

POWER DOWN

POWER DOWN EXIT15)

SELF REFRESH

SELF REFRESH EXIT16)

1) Action ACTIVATE starts with issuing the command and ends after tRCD.

2) During action ACTIVATE an ACT command on another bank is allowed considering tRRD, a PRE command on another bank is allowed

any time. WR, WR/A, RD and RD/A are always allowed.

3) Action WRITE starts with issuing the command and ends tWR after the first pos. edge of CLK following the last falling WDQS edge.

4) During action WRITE an ACT or a PRE command on another bank is allowed any time. A new WR or WR/A command on another bank

must be separated by at least one NOP from the ongoing WRITE. RD or RD/A are not allowed before tWTR is met.

5) Action WRITE/A starts with issuing the command and ends tWR after the first positive edge of CLK following the last falling WDQS edge.

6) During action WRITE/A an ACT or a PRE command on another bank is allowed any time. A new WR or WR/A command on another bank

has to be separated by at least one NOP from the ongoing command. RD is not allowed before or tWTR is met. RD/A is not allowed during

an ongoing WRITE/A action.

7) Action READ starts with issuing the command and ends with the first positive edge of CLK following the last falling edge of RDQS.

8) During action READ and READ/A an ACT or a PRE command on another bank is allowed any time. A new RD or RD/A command on

another bank has to be separated by at least one NOP from the ongoing command. A WR or WR/A command on another bank has to

meet tRTW.

9) Action READ/A starts with issuing the command and ends with the first positive edge of CLK following the last falling edge of RDQS.

10) Action PRECHARGE and PRECHARGE ALL start with issuing the command and ends after tRP.

Rev. 1.1, 2007-09

05292007-WAU2-UU95

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