E l e c t r i c a l C h a r a c t e r i s t i c s

SDRAM read

SDRAM read, CAS latency = 1

T1

active

read

T2

inhibit

prechg

bterm

BCLK

 

 

 

 

TA* (Note-3)

 

 

30

30

 

 

 

 

TEA*/LAST* (Note-3)

 

 

31

31

 

 

 

 

PortA2/AMUX

 

37

37

 

 

 

 

 

6

 

 

 

 

Non-muxed address

 

 

 

 

35

 

35

 

 

Muxed address

 

 

 

 

36

 

 

 

36

BE[3:0]* (DQM)

 

 

 

 

 

 

 

10

11

read D[31:0]

 

 

 

 

 

 

 

27

 

 

 

27

CS[4:0]*

 

 

 

 

34

 

34

 

 

CAS3* (RAS#)

 

 

 

 

CAS2* (CAS#)

 

34

34

 

 

 

 

 

34

34

 

34

34

CAS1* (WE#)

 

 

 

 

 

34

34

34

 

CAS0* (A10/AP)

A10

 

 

 

12

 

 

 

 

RW*

 

 

 

 

Notes:

 

 

 

 

1Port size determines which byte enable signals are active:

8-bit port = BE3*

16-bit port = BE[3:2]

32-bit port = BE[3:0]

T1

2The precharge and/or active commands are not always present. These commands depend on the address of the previous SDRAM access.

3The TA* and TEA*/LAST signals are for reference only.

w w w . d i g i . c o m

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Digi NS7520 manual Active Read Inhibit Prechg Bterm