74AC11648
OCTAL BUS TRANSCEIVER AND REGISTER
WITH 3-STATE OUTPUTS
SCAS114 – MARCH 1990 – REVISED APRIL 1993
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
Copyright  1993, Texas Instruments Incorporated
2–1
• Independent Registers for A and B Buses
• Multiplexed Real-Time and Stored Data
• Inverting Data Paths
• Flow-Through Architecture Optimizes
PCB Layout
• Center-Pin V
CC
and GND Configurations
Minimize High-Speed Switching Noise
• EPIC  (Enhanced-Performance Implanted
CMOS) 1-m m Process
• 500-mA Typical Latch-Up Immunity
at 125°C
• Package Options Include Plastic
Small-Outline Packages and Standard
Plastic 300-mil DIPs

description
The 74AC11648 consists of bus transceiver
circuits, D-type flip-flops, and control circuitry
arranged for multiplexed transmission of data
directly from the input bus or from the internal
registers. Data on the A or B bus is clocked into the registers on the low-to-high transition of the appropriate clock
(CLKAB or CLKBA) input. Figure 1 illustrates the four fundamental bus-management functions that can be
performed with the 74AC11648.
Output-enable (OE) and direction-control (DIR) inputs 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-control (SAB and SBA) inputs can multiplex stored and real-time (transparent mode) data. The
direction control (DIR) determines which bus will receive data when OE is low. In the isolation mode (OE 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 74AC11648 is characterized for operation from –40°C to 85°C.
DW OR NT PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
OE
A1
A2
A3
A4
GND
GND
GND
GND
A5
A6
A7
A8
DIR
CLKAB
SAB
B1
B2
B3
B4
V
CC
V
CC
B5
B6
B7
B8
CLKBA
SBA
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.