SN54AHC123A, SN74AHC123A

DUAL RETRIGGERABLE MONOSTABLE MULTIVIBRATORS

SCLS352H − JULY 1997 − REVISED OCTOBER 2005

9

POST OFFICE BOX 655303

APPLICATION INFORMATION

caution in use

power-down considerations

of energy stored in the capacitor. When a system containing this device is powered down, the capacitor can

t = (5 V)

× (15 pF)/30 mA = 2.5 ns. Usually, this is not a problem because power supplies are heavily filtered

can sustain damage. To avoid this possibility, use external clamping diodes.

output pulse duration

VCC

RT

CT

To Rext/Cext

Terminal

To Cext

Terminal

Figure 2. Timing-Component Connections

The pulse duration is given by:

+ K

R

T

C

T

where:

K

= multiplier factor

Equation 1 and Figure 3 can be used to determine values for pulse duration, external resistance, and external

capacitance.

(1)