
1
Data sheet acquired from Harris Semiconductor
SCHS248A
Features
’AC257, ’ACT257. . . . . . . . . . . . . Non-Inverting Outputs
CD74ACT258 . . . . . . . . . . . . . . . . . . . Inverting Outputs
Buffered Inputs
Typical Propagation Delay
- 4.4ns at V
CC
= 5V, T
A
= 25
o
C, C
L
= 50pF
Exceeds 2kV ESD Protection MIL-STD-883, Method
3015
SCR-Latchup-Resistant CMOS Process and Circuit
Design
Speed of Bipolar FAST/AS/S with Significantly
Reduced Power Consumption
Balanced Propagation Delays
AC Types Feature 1.5V to 5.5V Operation and
Balanced Noise Immunity at 30% of the Supply
±
24mA Output Drive Current
- Fanout to 15 FAST ICs
Drives 50
Transmission Lines
Pinout
CD54AC257, CD54ACT257
(CERDIP)
CD74AC257, CD74ACT257, CD74ACT258
(PDIP, SOIC)
TOP VIEW
Description
The ’AC257, ’ACT257 and CD74ACT258 are quad 2-input
multiplexers with three-state outputs that utilize Advanced
CMOS Logic technology. Each of these devices selects four
bits of data from two sources under the control of a common
Select input (S). The Output Enable (OE) is active LOW.
When OE is HIGH, all of the outputs (Y or Y) are in the high-
impedance state regardless of all other input conditions.
Moving data from two groups of registers to four common
output buses is a common use of the ’AC257, ’ACT257, and
CD74ACT258. The state of the Select input determines the
particular register from which the data comes. The ’AC257,
’ACT257 and CD74ACT258 can also be used as function
generators.
14
15
16
9
13
12
11
10
1
2
3
4
5
7
6
8
S
1I
0
1I
1
1Y
2I
0
2I
1
GND
2Y
V
CC
4I
0
4I
1
4Y
3I
0
3I
1
3Y
OE
AC/ACT257
ACT258
ACT258
V
CC
AC/ACT257
4I
0
4I
1
4Y
3I
0
3I
1
3Y
OE
S
1I
0
1I
1
1Y
2I
0
2I
1
GND
2Y
Ordering Information
PART
NUMBER
TEMP.
RANGE (
o
C)
PACKAGE
CD54AC257F3A
-55 to 125
16 Ld CERDIP
CD74AC257E
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
16 Ld PDIP
CD74AC257M
16 Ld SOIC
CD54ACT257F3A
-55 to 125
16 Ld CERDIP
CD74ACT257E
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
0 to 70
o
C, -40 to 85,
-55 to 125
16 Ld PDIP
CD74ACT257M
16 Ld SOIC
CD74ACT258E
16 Ld PDIP
CD74ACT258M
16 Ld SOIC
NOTES:
1. When ordering, use the entire part number. Add the suffix 96 to
obtain the variant in the tape and reel.
2. Wafer and die for this part number is available which meets all
electrical specifications. Please contact your local TI sales office or
customer service for ordering information.
August 1998 - Revised May 2000
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
FAST is a Trademark of Fairchild Semiconductor.
Copyright
2000, Texas Instruments Incorporated
CD54/74AC257, CD54/74ACT257,
CD74ACT258
Quad 2-Input Multiplexer
with Three-State Outputs