16

DEPTH EXPANSION — IDT72801/72811/72821/72831/72841/72851

can be adapted to applications that require greater than 256/512/1,024/

2,048/4,096/8,192 words. The existence of double enable pins on the read

and write ports allow depth expansion. The Write Enable 2/Load (WENA2,

WENB2) pins are used as a second write enables in a depth expansion

configuration, thus the Programmable flags are set to the default values.

Depth expansion is possible by using one enable input for system control

while the other enable input is controlled by expansion logic to direct the flow

of data. A typical application would have the expansion logic alternate data

accessfromonedevicetothenextinasequentialmanner. TheseFIFOsoperate

intheDepthExpansionconfigurationwhenthefollowingconditionsaremet:

1. WENA2/LDA and WENB2/LDB pins are held HIGH during Reset so

that these pins operate as second Write Enables.

2. External logic is used to control the flow of data.

Please see the Application Note" DEPTH EXPANSION OF IDT'S SYN-

CHRONOUS FIFOs USING THE RING COUNTER APPROACH" for details

of this configuration.

NOTES:

1

. Industrial temperature range product for 15ns and 25ns speed grade are available as a standard device.

2. Green parts are available. For specific speeds and packages contact your sales office.

LEAD FINISH (SnPb) parts are in EOL process. Product Discontinuation Notice - PDN# SP-17-02

ORDERING INFORMATION

BLANK

3034 drw 19

XXXXX

Device Type

XX

Power

Speed

Package

Process/

Temperature

Range

Clock Cycle Time

(tCLK), Speed in

Nanoseconds

Commercial (0°C to +70°C)

X

256 x 9 Dual SyncFIFO

Thin Quad Flatpack (TQFP, PN64-1)

10

72801

Commercial Only

PF

Low Power

XX

X

L

I(1)

Industrial (-40°C to +85°C)

TF

Slim Thin Quad Flatpack(STQFP, PP64-1)

15

25

Commercial and Industrial

Commercial and Industrial

72811

72821

72831

72841

72851

512 x 9 Dual SyncFIFO

1,024 x 9 Dual SyncFIFO

2,048 x 9 Dual SyncFIFO

4,096 x 9 Dual SyncFIFO

8,192 x 9 Dual SyncFIFO

X

G

(2)

Green

BLANK

8

Tube or Tray

Tape and Reel

X

DATASHEET DOCUMENT HISTORY

04/24/2001

pgs. 4, 5 and 16.

02/10/2006

pgs. 1 and 16.

01/13/2009

pg.

16.

03/20/2013

pg.

1, 3, 7 and 16.

02/01/2018

Product Discontinuation Notice - PDN# SP-17-02

Last time buy expires June 15, 2018.