74AC257
QUAD 2 CHANNEL MULTIPLEXER (3-STATE)
s
s
s
s
s
s
s
s
s
HIGH SPEED: tPD = 4.5ns (TYP.) at VCC = 5V
LOW POWER DISSIPATION:
ICC = 4µA(MAX.) at TA=25°C
HIGH NOISE IMMUNITY:
VNIH = V NIL = 28 % VCC (MIN.)
50Ω TRANSMISSION LINE DRIVING
CAPABILITY
SYMMETRICAL OUTPUT IMPEDANCE:
|IOH| = IOL = 24mA (MIN)
BALANCED PROPAGATION DELAYS:
tPLH ≅ tPHL
OPERATING VOLTAGE RANGE:
VCC (OPR) = 2V to 6V
PIN AND FUNCTION COMPATIBLE WITH
74 SERIES 257
IMPROVED LATCH-UP IMMUNITY
DESCRIPTION
The 74AC257 is an advanced high-speed CMOS
QUAD 2-CHANNEL MULTIPLEXER (3-STATE)
fabricated with sub-micron silicon gate and
double-layer metal wiring C2MOS tecnology.
It is composed of four independent 2-channel
multiplexer with common SELECT and ENABLE
(OE) inputs. It is a non-inverting multiplexer. When
the OE input is held HIGH,all the output become in
(s)
ct
DIP
SOP
TSSOP
ORDER CODES
PACKAGE
TUBE
DIP
SOP
TSSOP
74AC257B
74AC257M
s)
t(
T&R
ro
P
uc
d
74AC257MTR
74AC257TTR
high impedance state. If SELECT input is held
LOW, "A" data is selected, when SELECT input is
held HIGH, "B" data is chosen.
All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.
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PIN CONNECTION AND IEC LOGIC SYMBOLS
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74AC257
ABSOLUTE MAXIMUM RATINGS
Symbol
VCC
Parameter
Value
Supply Voltage
Unit
-0.5 to +7
V
-0.5 to VCC + 0.5
-0.5 to VCC + 0.5
V
DC Input Diode Current
± 20
mA
IOK
DC Output Diode Current
± 20
mA
IO
DC Output Current
± 50
mA
± 200
mA
VI
DC Input Voltage
VO
DC Output Voltage
IIK
ICC or IGND DC VCC or Ground Current
Tstg
Storage Temperature
TL
Lead Temperature (10 sec)
V
-65 to +150
°C
300
°C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied.
RECOMMENDED OPERATING CONDITIONS
Symbol
VCC
Parameter
Value
Supply Voltage
Input Voltage
VO
Output Voltage
Top
Operating Temperature
dt/dv
Unit
uc
2 to 6
VI
s)
t(
0 to VCC
od
r
V
V
0 to VCC
eP
let
Input Rise and Fall Time VCC = 3.0, 4.5 or 5.5V (note 1)
1) VIN from 30% to 70% of V CC
(s)
ct
V
-55 to 125
°C
8
ns/V
so
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