Datasheet

1998 Jul 08 4
Philips Semiconductors Product specification
Dual retriggerable monostable
multivibrator with reset
74HC/HCT123
Fig.4 Functional diagram.
FUNCTION TABLE
Note
1. If the monostable was triggered
before this condition was
established, the pulse will
continue as programmed.
INPUTS OUTPUTS
nR
D
nAnBnQ nQ
LXXL H
XHX L
(1)
H
(1)
XX L L
(1)
H
(1)
HL ↑
H↓ H
↑LH
H = HIGH voltage level
L = LOW voltage level
X = don’t care
↑ = LOW-to-HIGH transition
↓ = HIGH-to-LOW transition
= one HIGH level output pulse
= one LOW level output pulse
Fig.5 Logic diagram.
(1) For minimum noise generation,
it is recommended to ground pins 6 (2C
EXT
)
and 14 (1C
EXT
) externally to pin 8 (GND).