SN74ACT2235 Datasheet, PDF (1/18 Pages) Texas Instruments – 1024 × 9 × 2 ASYNCHRONOUS BIDIRECTIONAL FIRST-IN, FIRST-OUT MEMORY

SN74ACT2235
1024 × 9 × 2
ASYNCHRONOUS BIDIRECTIONAL FIRST-IN, FIRST-OUT MEMORY
SCAS148F – DECEMBER 1990 – REVISED JUNE 2003
D Independent Asynchronous Inputs and
Outputs
D Low-Power Advanced CMOS Technology
D Bidirectional
D Dual 1024 by 9 Bits
D Programmable Almost-Full/Almost-Empty
Flag
D Empty, Full, and Half-Full Flags
D Access Times of 25 ns With a 50-pF Load
D Data Rates up to 50 MHz
D Fall-Through Times of 22 ns Maximum
D High Output Drive for Direct Bus Interface
D Package Options Include 44-Pin Plastic
Leaded Chip Carriers (FN) and 64-Pin Thin
Quad Flat (PAG, PM) Packages
description
A FIFO memory is a storage device that allows data to be written into and read from its array at independent
data rates. The SN74ACT2235 is arranged as two 1024 × 9-bit FIFOs for high speed and fast access times.
It processes data at rates up to 50 MHz, with access times of 25 ns in a bit-parallel format.
The SN74ACT2235 consists of bus-transceiver circuits, two 1024 × 9-bit FIFOs, and control circuitry arranged
for multiplexed transmission of data directly from the data bus or from the internal FIFO memories. Enable (GAB
and GBA) inputs are provided to control the transceiver functions. The select-control (SAB and SBA) inputs are
provided to select whether real-time or stored data is transferred. The circuitry used for select control eliminates
the typical decoding glitch that occurs in a multiplexer during the transition between stored and real-time data.
Figure 2 shows the eight fundamental bus-management functions that can be performed with the
SN74ACT2235.
For more information on this device family, see the application report, 1K × 9 × 2 Asynchronous FIFO
SN74ACT2235, literature number SCAA010.
The SN74ACT2235 is characterized for operation from 0°C to 70°C.
FN PACKAGE
(TOP VIEW)
A3
A4
V_CC
A5
A6
A7
A8
GND
AF/AEA
HFA
LDCKA
6 5 4 3 2 1 44 43 42 41 40
7
39
8
38
9
37
10
36
11
35
12
34
13
33
14
32
15
31
16
30
17
29
18 19 20 21 22 23 24 25 26 27 28
B2
B3
B4
V_CC
B5
B6
B7
B8
GND
AF/AEB
HFB
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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.
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