IDT723631 Просмотр технического описания (PDF) - Integrated Device Technology

Номер в каталоге

Компоненты Описание

Список матч

IDT723631

CMOS SyncFIFO 512 x 36, 1024 x 36, 2048 x 36

Integrated Device Technology 

IDT723631/723641/723651 CMOS SyncFIFO™

512 x 36, 1024 x 36, 2048 x 36

PIN DESCRIPTION (CONTINUED)

COMMERCIAL TEMPERATURE RANGE

Symbol

Name

MBF2 Mail2 Register Flag

OR Output-Ready Flag

RFM Read From Mark

RST Reset

RTM Retransmit Mode

W/RA Port-A Write/Read

Select

W/RB Port-B Write/Read

Select

I/O

Description

O MBF2 is set LOW by the LOW-to-HIGH transition of CLKB that writes data to

the mail2 register. MBF2 is set HIGH by a LOW-to-HIGH transition of CLKA

when a port-A read is selected and MBA is HIGH. MBF2 is set HIGH by a

reset.

O OR is synchronized to the LOW-to-HIGH transition of CLKB. When OR is

LOW, the FIFO is empty and reads are disabled. Ready data is present in the

output register of the FIFO when OR is HIGH. OR is forced LOW during the

reset and goes HIGH on the third LOW-to-HIGH transition of CLKB after a

word is loaded to empty memory.

I When the FIFO is in retransmit mode, a HIGH on RFM enables a LOW-to-

HIGH transition of CLKB to reset the read pointer to the beginning retransmit

location and output the first selected retransmit data.

I To reset the device, four LOW-to-HIGH transitions of CLKA and four LOW-to-

HIGH transitions of CLKB must occur while RST is LOW. The LOW-to-HIGH

transition of RST latches the status of FS0 and FS1 for AF and AE offset

selection.

I When RTM is HIGH and valid data is present in the FIFO output register (OR

is HIGH), a LOW-to-HIGH transition of CLKB selects the data for the begin-

ning of a retransmit and puts the FIFO in retransmit mode. The selected word

remains the initial retransmit point until a LOW-to-HIGH transition of CLKB

occurs while RTM is LOW, taking the FIFO out of retransmit mode.

I A HIGH selects a write operation and a LOW selects a read operation on

port A for a LOW-to-HIGH transition of CLKA. The A0-A35 outputs are in the

high-impedance state when W/RA is HIGH.

I A LOW selects a write operation and a HIGH selects a read operation on

port B for a LOW-to-HIGH transition of CLKB. The B0-B35 outputs are in the

high-impedance state when W/RB is LOW.

3023 tbl 02

5

Share Link: