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DM74LS123
Absolute Maximum Ratings(Note 1) Note 1: The “Absolute Maximum Ratings” are thos e values bey ond which
the saf ety of the device cannot be gu aranteed. Th e device shoul d not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “R ecomm ended Oper ating Co ndition s” table will def ine the condit ions
for actu al device operation.
Recommended Operating Conditions
Note 2: TA = 25°C and VCC = 5V.
Electrical Characteristics
over recommended operating free air temperature range (unless otherwise noted)
Note 3: All typical s are at VCC = 5V, TA = 25°C.
Note 4: Not more tha n one out put shoul d be shorte d at a t im e, and the duration sh ould not ex c eed one s ec ond.
Note 5: Quiescent ICC is me as ured (aft er clearin g) with 2.4V applied to all c lear and A inputs, B inputs gr ounded, all outputs OPEN , CEXT = 0.02 µF,
and REXT = 25 kΩ.
Note 6: ICC is measu red in the tri ggered sta t e w it h 2. 4V applie d t o all clear and B inputs , A inputs gro unded, all outputs OPEN, CEXT = 0.02 µF,
and REXT = 25 kΩ.
Note 7: With all outputs OPEN and 4.5V applied to all data and clear inputs, ICC is measure d af t er a mome nt ary grou nd, then 4.5V is applied to the clock.
Supply Voltage 7V
Input Voltag e 7V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature −65°C to +150°C
Symbol Parameter Min Nom Max Units
VCC Supply Voltage 4.75 5 5.25 V
VIH HIGH Level Input Voltage 2 V
VIL LOW Level Inp ut Voltage 0.8 V
IOH HIGH Level Output Current −0.4 mA
IOL LOW Level Output Current 8 mA
tWPulse Widt h A or B HIGH 40
(Note 2) A or B LOW 40 ns
Clear LOW 40
REXT External Timing Resistor 5 260 kΩ
CEXT External Timing Capacitance No Restriction µF
CWIRE Wiring Capacitance at REXT/CEXT Termina l 50 pF
TAFree Air Ope rat ing Temper atu re 0 70 °C
Symbol Parameter Conditions Min Typ Max Units
(Note 3)
VIInput Clamp Voltage VCC = Min, II = −18 mA −1.5 V
VOH HIGH Level VCC = Min, IOH = Max 2.7 3.4 V
Output Voltage VIL = Max, VIH = Min
VOL LOW Level VCC = Min, IOL = Max 0.35 0.5
Output Voltage VIL = Max, VIH = Min V
IOL = 4 mA, VCC = Min 0.25 0.4
IIInput Current @ Max Input Voltage VCC = Max, VI = 7V 0.1 mA
IIH HIGH Level Input Current V CC = Max, VI = 2.7V 20 µA
IIL LOW Level Input Current VCC = Max, VI = 0.4V −0.4 mA
IOS Short Circuit Output Current VCC = Max (Note 4) −20 −100 mA
ICC Supply Current VCC = Max (Note 5)(Note 6)(Note 7) 12 20 mA