5.08

10

IDT72V01/72V02/72V03/72V04 3.3 VOLT CMOS ASYNCHRONOUS FIFO

512 x 9, 1,024 x 9, 2,048 x 9, 4,096 x 9

COMMERCIAL TEMPERATURE RANGE

TABLE II—RESET AND FIRST LOAD TRUTH TABLE

Depth Expansion/Compound Expansion Mode

Inputs

Internal Status

Outputs

Mode

RS

RS

FL

FL

XI

XI

Read Pointer

Write Pointer

EF

EF

FF

FF

Reset First Device

0

0

(1)

Location Zero

Location Zero

0

1

Reset All Other Devices

0

1

(1)

Location Zero

Location Zero

0

1

Read/Write

1

X

(1)

X

X

X

X

NOTE:

2679 tbl 10

1.

XI is connected to XO of previous device. See Figure 14. RS = Reset Input, FL/RT = First Load/Retransmit, EF = Empty Flag Output, FF = Flag Full Output,

XI = Expansion Input, HF = Half-Full Flag Output

TABLE I—RESET AND RETRANSMIT

Single Device Configuration/Width Expansion Mode

Inputs

Internal Status

Outputs

Mode

RS

RS

RT

RT

XI

XI

Read Pointer

Write Pointer

EF

EF

FF

FF

HF

HF

Reset

0

X

0

Location Zero

Location Zero

0

1

1

Retransmit

1

0

0

Location Zero

Unchanged

X

X

X

Read/Write

1

1

0

Increment

(1)

Increment

(1)

XX

X

NOTE:

2679 tbl 09

1. Pointer will increment if flag is High.

Figure 12. Block Diagram of Single 1024 x 9 FIFO

2679 drw 15

Figure 13. Block Diagram of 1024 x 18 FIFO Memory Used in Width Expansion Mode

WRITE (

W)

DATA IN (D)

FULL FLAG (

FF)

RESET (

RS)

9

READ (

R)

9

DATA OUT (Q)

EMPTY FLAG (

EF)

RETRANSMIT (

RT)

EXPANSION IN (

XI)

(

HF)

IDT

72V01

72V02

72V03

72V04

(HALF–FULL FLAG)

2679 drw 14

IDT

72V01

72V02

72V03

72V04

XI

XI

99

18

9

18

HF

HF

9

DATA

WRITE (

W)

FULL FLAG (

FF)

RESET (

RS)

(D)

IN

READ (

R)

EMPTY FLAG (

EF)

RETRANSMIT (

RT)

DATA

(Q)

OUT

IDT

72V01

72V02

72V03

72V04