74ACT11648 Datasheet, PDF (1/10 Pages) Texas Instruments – OCTAL BUS TRANSCEIVER AND REGISTER WITH 3-STATE OUTPUTS

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74ACT11648
OCTAL BUS TRANSCEIVER AND REGISTER
WITH 3ĆSTATE OUTPUTS
SCAS115 − D3458, MARCH 1990 − REVISED APRIL 1993
• Inputs Are TTL-Voltage Compatible
DW PACKAGE
• Independent Registers A and B Buses
(TOP VIEW)
• Multiplexed Real-Time and Stored Data
• Inverting Data Paths
G1
A1 2
28 CAB
27 SAB
• Flow-Through Architecture to Optimize
A2 3
26 B1
PCB Layout
A3 4
25 B2
• Center-Pin V_CC and GND Configurations
Minimize High-Speed Switching Noise
• EPICt (Enhanced-Performance Implanted
CMOS) 1-mm Process
• 500-mA Typical Latch-Up Immunity
at 125°C
A4 5
GND 6
GND 7
GND 8
GND ⁹
A5 ¹⁰
A6 ¹¹
24 B3
23 B4
22 V_CC
21 V_CC
20 _B5
19 _B6
18 _B7
description
A7 ¹²
A8 ¹³
17 _B8
16 _CBA
The 74ACT11648 consists of bus transceiver
DIR ^{14 15} SBA
circuits with 3-state outputs, D-type flip-flops, and
control circuitry arranged for multiplexed trans-
mission of data directly from the data bus or from
the internal storage registers. Data on the A or B bus will be clocked into the registers on the low-to-high
transition of the appropriate clock pin (CAB or CBA). Examples of the four fundamental bus-management
functions that can be performed with the octal bus transceivers and registers are shown in Figure 1.
Enable (G) and direction (DIR) pins are provided to control the transceiver functions. In the transceiver mode,
data present at the high-impedance port may be stored in either register or in both. The select controls (SAB
and SBA) can multiplex stored and real-time (transparent mode) data. The circuitry used for select control will
eliminate the typical decoding glitch that occurs in a mulitplexer during the transition between stored and
real-time data. The direction control determines which bus will receive data when enable G is active (low). In
the isolation mode (control G high), A data may be stored in one register and/or B data may be stored in the
other register.
When an output function is disabled, the input function is still enabled and may be used to store and transmit
data. Only one of the two buses, A or B, may be driven at a time.
The 74ACT11648 is characterized for operation from − 40°C to 85°C.
EPIC is a trademark of 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.
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Copyright  1993, Texas Instruments Incorporated
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