M54/M74HCT257
M54/M74HCT258
HCT257 QUAD 2 CHANNEL MULTIPLEXER (3-STATE)
HCT258 QUAD 2 CHANNEL MULTIPLEXER (3-STATE,INVERTING)
.HIGH SPEED
tPD= 16 ns(TYP.) at VCC=5V
.LOWPOWER DISSIPATION
ICC=4µA(MAX.) atTA=25°C
.COMPATIBLE WITH TTL OUTPUTS
VIH= 2V(MIN.)VIL= 0.8V (MAX)
.OUTPUTDRIVECAPABILITY
15 LSTTLLOADS
B1R
(PlasticPackage)
F1R
(CeramicPackage)
.SYMMETRICALOUTPUT IMPEDANCE
IOH =IOL= 6 mA (MIN.)
.BALANCEDPROPAGATIONDELAYS
t
PLH=tPHL
.PIN AND FUNCTION COMPATIBLE
WITH 54/74LS257/258
M1R
(MicroPackage)
ORDER CODES :
M54HC TXXX F 1R M74H CTXXXM1R
M74HC TXXX B1R M74HCT XXX C1R
C1R
(Chip Carrier)
DESCRIPTION
The M54/74HCT257 and the M54/74HCT258 are
highspeed CMOSMULTIPLEXERsfabricated with
silicongate C2MOS technology.
They have the same high speed performance of
LSTTL combined with true CMOS low power consumption.
These IC’s are composed of an independent 2channelmultiplexer withcommonSELECT andENABLE INPUT.
The M54/74HCT258 is an inverting multiplexer
while the M54/74HCT257 is a non-inverting multiplexer. When the ENABLE INPUT is held ”High”,
outputs of both IC’sbecome high-impedance state.
IfSELECTINPUTisheld”Low”,”A”dataisselected,
when SELECT INPUT is high ”H”, ”B” data is
chosen.
All inputs are equipped with protection circuits
against static discharge and transient excess voltage.
This integrated circuit has input and output characteristicsthat are fully compatible with 54/74 LSTTL
logic families. M54/74HCT devices are designed to
directly interface HSC2MOSsystems with TTLand
NMOS components. They are also plug in replace-
PIN CONNECTIONS(topview)
HCT257
HCT258
February 1993
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M54/M74HCT257/258
INPUT AND OUTPUT EQUIVALENT CIRCUIT
CHIP CARRIER
HCT257 HCT258
NC = No Internal Connection
PIN DESCRIPTION ( HCT 257)
PIN No SYMBOL NAME AND FUNCTION
1 SELECT Common Data Select
Input
2, 5, 14, 11 1A to 4A Data Input From Source A
3, 6, 13, 10 1B to 4B Data Inputs from Source B
4, 7, 12, 9 1Y to 4Y 3 State Multiplexer
Outputs
15 OE 3 State Output Enable
Inputs (Active LOW)
8 GND Ground (0V)
16 V
CC
Positive Supply Voltage
PIN DESCRIPTION (HCT258)
PIN No SYMBOL NAME AND FUNCTION
1 SELECT Common Data Select
Input
2, 5, 14, 11 1A to 4A Data Input From Source A
3, 6, 13, 10 1B to 4B Data Inputs from Source B
4, 7, 12, 9 1Y to 4Y 3 State Multiplexer
Outputs
15 OE 3 State Output Enable
Inputs (Active LOW)
8 GND Ground (0V)
16 V
CC
Positive Supply Voltage
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IEC LOGIC SYMBOL
LOGIC DIAGRAM
M54/M74HCT257/258
HCT258HCT257
HCT257 HCT258
TRUTH TABLE
OE SELECT A B Y (257) Y (258)
HXXXZZ
LLLXLH
LLHXHL
LHXLLH
LHXHHL
X =DON’TCARE Z = HIGHIMPEDANCE
INPUTS OUTPUTS
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M54/M74HCT257/258
ABSOLU TE MAXIMU M RAT I NG S
Symbol Parameter Value Unit
V
CC
V
V
O
I
IK
I
OK
I
O
I
or I
CC
P
D
T
stg
T
AbsoluteMaximumRatingsarethosevalues beyondwhichdamagetothedevicemayoccur.Functionaloperationunder theseconditionisnotimplied.
(*)500 mW:≅ 65oC derateto 300mW by 10mW/oC: 65oCto85oC
RECO MM ENDED OPERATIN G CONDI TI O NS
Symbol Parameter Value Unit
V
CC
V
I
V
O
T
op
t
r,tf
Supply Voltage -0.5 to +7 V
DC Input Voltage -0.5 to VCC+ 0.5 V
I
DC Output Voltage -0.5 to VCC+ 0.5 V
DC Input Diode Current ± 20 mA
DC Output Diode Current ± 20 mA
DC Output Source Sink Current Per Output Pin ± 35 mA
DC VCCor Ground Current ± 70 mA
GND
Power Dissipation 500 (*) mW
Storage Temperature -65 to +150
Lead Temperature (10 sec) 300
L
Supply Voltage 4.5 to 5.5 V
Input Voltage 0 to V
Output Voltage 0 to V
Operating Temperature: M54HC Series
M74HC Series
CC
CC
-55 to +125
-40 to +85
Input Rise and Fall Time (VCC= 4.5 to 5.5V) 0 to 500 ns
o
C
o
C
V
V
o
C
o
C
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