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HD74HC78 Datasheet, PDF (1/7 Pages) Hitachi Semiconductor – Dual J-K Flip-Flops (with Preset, Common Clear and Common Clock)
HD74HC78
Dual J-K Flip-Flops
(with Preset, Common Clear and Common Clock)
REJ03D0553-0200
(Previous ADE-205-425)
Rev.2.00
Oct 06, 2005
Description
This flip-flop is edge sensitive to the clock input and change state on the negative transition of the clock pulse. Each
flip-flop has independent J, K, and preset inputs and Q and Q outputs. Two flip-flops are controlled by a common clear
and a common clock. Preset and clear are independent of the clock and accomplished by a low logic level on the
corresponding input.
Features
• High Speed Operation: tpd (Clock to Q) = 20 ns typ (CL = 50 pF)
• High Output Current: Fanout of 10 LSTTL Loads
• Wide Operating Voltage: VCC = 2 to 6 V
• Low Input Current: 1 µA max
• Low Quiescent Supply Current: ICC (static) = 2 µA max (Ta = 25°C)
• Ordering Information
Part Name
Package Type
Package Code
(Previous Code)
Package
Abbreviation
HD74HC78FPEL SOP-14 pin (JEITA)
PRSP0014DF-B
(FP-14DAV)
FP
HD74HC78RPEL SOP-14 pin (JEDEC) PRSP0014DE-A RP
(FP-14DNV)
Note: Please consult the sales office for the above package availability.
Taping Abbreviation
(Quantity)
EL (2,000 pcs/reel)
EL (2,500 pcs/reel)
Function Table
Inputs
Outputs
Preset
Clear
Clock
J
K
Q
Q
L
H
X
X
X
H
L
H
L
X
X
X
L
H
L
L
X
X
X
H*1
H*1
H
H
L
L
No change
H
H
L
H
L
H
H
H
H
L
H
L
H
H
H
H
Toggle
H
H
L
X
X
No change
H
H
H
X
X
No change
H
H
X
X
No change
H : High level
L : Low level
X : Irrelevant
Note: 1. Q and Q will remain High as long as Preset and Clear are Low, but Q and Q are unpredictable, if Preset and
Clear go High simultaneously.
Rev.2.00, Oct 06, 2005 page 1 of 6