Datasheet

74HC_HCT123 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2015. All rights reserved.
Product data sheet Rev. 9 — 19 January 2015 15 of 25
NXP Semiconductors
74HC123; 74HCT123
Dual retriggerable monostable multivibrator with reset
12. Application information
12.1 Timing component connections
The basic output pulse width is essentially determined by the values of the external timing
components R
EXT
and C
EXT
.
12.2 Power-up considerations
When the monostable is powered-up it may produce an output pulse, with a pulse width
defined by the values of R
EXT
and C
EXT
. This output pulse can be eliminated using the
circuit shown in Figure 14
.
(1) For minimum noise generation it is recommended to ground pins 6 (2CEXT) and 14 (1CEXT)
externally to pin 8 (GND).
Fig 13. Timing component connections
DDD
&
(;7
5
(;7
Q$
Q%
9
&&
Q&(;7
Q5'
Q5(;7&(;7
Q4
Q4
*1'









Fig 14. Power-up output pulse elimination circuit
DDD
9
&&
5(6(7
Q5'
&
(;7
5
(;7
Q$
Q%
9
&&
Q&(;7*1' Q5(;7&(;7
Q4
Q4






