
.HIGH SPEED
tPD= 12 ns(TYP.) AT VCC=5V
.LOWPOWERDISSIPATION
ICC=4µA(MAX.) AT TA=25°C
.OUTPUTDRIVE CAPABILITY
10 LSTTL LOADS
.SYMMETRICALOUTPUT IMPEDANCE
IOH =IOL= 4 mA(MIN.)
.BALANCEDPROPAGATION DELAYS
t
PLH=tPHL
.HIGH NOISE IMMUNITY
V
NIH=VNIL
=28%VCC(MIN.)
.WIDE OPERATINGVOLTAGE RANGE
VCC(OPR)= 2 V TO6 V
.PIN ANDFUNCTION COMPATIBLE
WITH 54/74LS194
M54HC194
M74HC194
4 BITPIPO SHIFT REGISTER
B1R
(PlasticPackage)
M1R
(MicroPackage)
ORDER CODES :
M54HC 194F1R M74H C194M1R
M74HC 194B1R M74HC1 94C1R
F1R
(CeramicPackage)
C1R
(Chip Carrier)
DESCRIPTION
TheM54/74HC194 isahighspeedCMOS4BITPIPO
SHIFTREGISTER fabricated insilicongate C2MOS
technology. It has the same high speed performance
ofLSTTLcombined withtrue CMOSlowpowerconsumption.This SHIFT REGISTER is designed to incorporatevirtuallyallofthefeaturesasystemdesigner
maywantina shiftregister. Itfeatures parallel inputs,
parallel outputs, right shift and left shift serial inputs,
clearline.Theregisterhas fourdistinctmodesofoperation: PARALLEL (broadside) LOAD;SHIFTRIGHT
(in the direction QAQD); SHIFT LEFT ; INHIBIT
CLOCK(donothing).Synchronous parallel loadingis
accomplishedbyapplyingthefourdatabitsandtaking
bothmode control inputs, S0 and S1 high.The data
areloaded intotheir respective flip-flops and appear
at the outputs after the positive transition of the
CLOCK input. During loading, serial data flow is inhibited.Shiftright isaccomplished synchronouslywith
therising edge oftheclockpulsewhenS0is highand
S1 is low.Serial dataforthis mode is entered at the
SHIFTRIGHTdata input. When S0 is lowand S1 is
high,datashiftsleftsynchronously andnewdataisentered at the SHIFT LEFTserialinput. Clockingof the
flipflopsisinhibitedwhenbothmodecontrolinputsare
low.The modecontrol inputs should bechangedonly
whentheCLOCKinput ishigh. Allinputsareequipped
with protection circuits against static discharge and
transientexcessvoltage.
NC =
No Internal
Connection
PIN CONNECTIONS(top view)
October 1992
1/12

M54/M74HC194
INPUT AND OUTPUT EQUIVALENT CIRCUIT
PIN DESCRIPTION
PIN No SYMBOL NAME AND FUNCTION
1 CLEAR Asynchronous Reset
Input (Active LOW)
2 SR Serial Data Input (Shift
Right)
3, 4, 5, 6 A to D Parallel Data Input
7 SL Serial Data Input (Shift
Left)
9, 10 S0, S1 Mode Control Inputs
11 CLOCK Clock Input (LOW to
HIGH Edge-triggered)
15, 14, 13, 12 QA to QD Paralle Outputs
8 GND Ground (0V)
16 V
CC
Positive Supply Voltage
IEC LOGIC SYMBOL
TRUTH TABLE
INPUTS OUTPUS
CLEAR MODE
S1 S0 LEFT RIGHT ABCD
L X X X X X XXXX L L L L
H X X X X XXXXQA0QB0QC0QD0
H H H X X abcd a b c d
H L H X H XXXX HQAnQBnQCn
H L H X L XXXX L QAnQBnQCn
H H L H X XXXXQBnQCnQDnH
H H L L X XXXXQBnQCnQDnL
H L L X X X XXXXQA0QB0QC0QD0
X: Don’t Care : Don’t Care
a ~d : The level of steady state input voltage at inputA ~ D respactively
QA0~ QD0 : No change
QAn~ QDn : The level of QA, QB,QC, respectively, before themst recent positive transition oftheclock.
CLOCK
SERIAL PARALLEL
QA QB QC QD
2/12

M54/M74HC194
ABSOLU TE MAXIMU M RATINGS
Symbol Parameter Value Unit
V
CC
V
V
O
I
IK
I
OK
I
O
I
or I
CC
P
D
T
stg
T
L
AbsoluteMaximumRatingsarethose values beyondwhichdamage tothedevicemayoccur. Functionaloperationunder these conditionisnotimplied.
(*)500 mW: ≅ 65oC derateto300mWby 10mW/oC: 65oCto85oC
RECO MM ENDED O PERAT IN G C O NDITI 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 ± 25 mA
DC VCCor Ground Current ± 50 mA
GND
Power Dissipation 500 (*) mW
Storage Temperature -65 to +150
Lead Temperature (10 sec) 300
Supply Voltage 2 to 6 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= 2 V 0 to 1000 ns
V
= 4.5 V 0 to 500
CC
V
= 6 V 0 to 400
CC
o
C
o
C
V
V
o
C
o
C
4/12