SN74ABT3611

64

× 36

CLOCKED FIRST-IN, FIRST-OUT MEMORY

SCBS127E – JULY 1992 – REVISED APRIL 1998

1

POST OFFICE BOX 655303

Asynchronous or Coincident

Port A to Port B

Almost-Empty Flags

Synchronized by CLKA

Synchronized by CLKB

Port

Quad Flat (PCB) and 132-Pin Plastic Quad

Flat (PQ) Packages

description

The SN74ABT3611 is a high-speed, low-power BiCMOS clocked FIFO memory. It supports clock frequencies

up to 67 MHz and has read access times as fast as 10 ns. A 64

× 36 dual-port SRAM FIFO buffers data from

port A to port B. The FIFO has flags to indicate empty and full conditions and two programmable flags (almost

full and almost empty) to indicate when a selected number of words is stored in memory. Communication

between each port takes place through two 36-bit mailbox registers. Each mailbox register has a flag to signal

when new mail has been stored. Parity is checked passively on each port and can be ignored if not desired.

Parity generation can be selected for data read from each port. Two or more devices are used in parallel to create

wider datapaths.

The SN74ABT3611 is a clocked FIFO, which means each port employs a synchronous interface. All data

transfers through a port are gated to the low-to-high transition of a port clock by enable signals. The clocks for

each port are independent of one another and can be asynchronous or coincident. The enables for each port

are arranged to provide a simple bidirectional interface between microprocessors and/or buses with

synchronous control.

The full flag (FF) and almost-full (AF) flag of the FIFO are two-stage synchronized to the port clock that writes

data to its array (CLKA). The empty flag (EF) and almost-empty (AE) flag of the FIFO are two-stage

synchronized to the port clock that reads data from its array.

The SN74ABT3611 is characterized for operation from 0

°C to 70°C.

For more information on this device family, see the following application reports:

number SCAA007)

(literature number SCAA015)

Copyright

© 1998, Texas Instruments Incorporated

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.