beautypg.com

Analog Devices ADSP-21020 User Manual

Page 18

background image

ADSP-21020

REV. C

–18–

Memory Read

K/B/T Grade

K/B/T Grade

B/T Grade

K Grade

20 MHz

25 MHz

30 MHz

33.3 MHz Frequency Dependence*

Parameter

Min

Max

Min

Max

Min Max Min Max Min

Max

Unit

Timing Requirement:
t

DAD

Address, Select to Data Valid

37

27

20

17

37 + DT

ns

t

DRLD

xRD

Low to Data Valid

24

18

13

11

24 + 5DT/8

ns

t

HDA

Data Hold from Address, Select

0

0

0

0

ns

t

HDRH

Data Hold from xRD High

–1

–1

–1

–1

ns

t

DAAK

xACK Delay from Address

27

18

12

9

27 + 7DT/8

ns

t

DRAK

xACK Delay from xRD Low

15

10

6

5

15 + DT/2

ns

t

SAK

xACK Setup before CLKIN High

14

12

10

9

14 + DT/4

ns

t

HAK

xACK Hold after CLKIN High

0

0

0

0

ns

Switching Characteristic:
t

DARL

Address, Select to xRD Low

8

4

2

0

8 + 3DT/8

ns

t

DAP

xPAGE Delay from Address, Select

1

1

1

1

ns

t

DCKRL

CLKIN High to xRD Low

16

26

13

24

12

22

11

21

16 + DT/4 26 + DT/4

ns

t

RW

xRD

Pulse Width

26

20

15

13

26 + 5DT/8

ns

t

RWR

xRD

High to xRD, xWD Low

17

13

11

9

17 + 3DT/8

ns

NOTES
*DT = t

CK

– 50 ns

x = PM or DM; Address = PMA23-0, DMA31-0; Data = PMD47-0, DMD39-0; Select = PMS1-0, DMS3-0.