Motore di ricerca datesheet componenti elettronici
  Italian  ▼
ALLDATASHEETIT.COM

X  

DM74LS123NX Scheda tecnica(PDF) 2 Page - Fairchild Semiconductor

Il numero della parte DM74LS123NX
Spiegazioni elettronici  Dual Retriggerable One-Shot with Clear and Complementary Outputs
Download  8 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Produttore elettronici  FAIRCHILD [Fairchild Semiconductor]
Homepage  http://www.fairchildsemi.com
Logo FAIRCHILD - Fairchild Semiconductor

DM74LS123NX Scheda tecnica(HTML) 2 Page - Fairchild Semiconductor

  DM74LS123NX Datasheet HTML 1Page - Fairchild Semiconductor DM74LS123NX Datasheet HTML 2Page - Fairchild Semiconductor DM74LS123NX Datasheet HTML 3Page - Fairchild Semiconductor DM74LS123NX Datasheet HTML 4Page - Fairchild Semiconductor DM74LS123NX Datasheet HTML 5Page - Fairchild Semiconductor DM74LS123NX Datasheet HTML 6Page - Fairchild Semiconductor DM74LS123NX Datasheet HTML 7Page - Fairchild Semiconductor DM74LS123NX Datasheet HTML 8Page - Fairchild Semiconductor  
Zoom Inzoom in Zoom Outzoom out
 2 / 8 page
background image
www.fairchildsemi.com
2
Functional Description
The basic output pulse width is determined by selection of
an external resistor (RX) and capacitor (CX). Once trig-
gered, the basic pulse width may be extended by retrigger-
ing the gated active-LOW transition or active-HIGH
transition inputs or be reduced by use of the active-LOW or
CLEAR input. Retriggering to 100% duty cycle is possible
by application of an input pulse train whose cycle time is
shorter than the output cycle time such that a continuous
“HIGH” logic state is maintained at the “Q” output.
Operating Rules
1. An external resistor (RX) and an external capacitor (CX)
are required for proper operation. The value of CX may
vary from 0 to any necessary value. For small time con-
stants high-grade mica, glass, polypropylene, polycar-
bonate, or polystyrene material capacitors may be
used. For large time constants use tantalum or special
aluminum capacitors. If the timing capacitors have
leakages approaching 100 nA or if stray capacitance
from either terminal to ground is greater than 50 pF the
timing equations may not represent the pulse width the
device generates.
2. When an electrolytic capacitor is used for CX a switch-
ing diode is often required for standard TTL one-shots
to prevent high inverse leakage current. This switching
diode is not needed for the DM74LS123 one-shot and
should not be used. In general the use of the switching
diode is not recommended with retriggerable operation.
Furthermore, if a polarized timing capacitor is used on
the DM74LS123 the negative terminal of the capacitor
should be connected to the “CEXT” pin of the device
(Figure 1).
FIGURE 1.
3. For CX >> 1000 pF the output pulse width (tW) is
defined as follows:
tW = KRX CX
where [RX is in kΩ]
[CX is in pF]
[tW is in ns]
K
≈ 0.37
4. The multiplicative factor K is plotted as a function of CX
below for design considerations:
FIGURE 2.
5. For CX < 1000 pF see Figure 3 for tW vs. CX family
curves with RX as a parameter:
FIGURE 3.
6. To obtain variable pulse widths by remote trimming, the
following circuit is recommended:
FIGURE 4.
“Rremote” should be as close to the device pin as possible.
7. The retriggerable pulse width is calculated as shown
below:
T
= t
W + tPLH = K × RX × CX + tPLH
The retriggered pulse width is equal to the pulse width
plus a delay time period (Figure 5).
FIGURE 5.


Codice articolo simile - DM74LS123NX

Produttore elettroniciIl numero della parteScheda tecnicaSpiegazioni elettronici
logo
National Semiconductor ...
DM74LS123N NSC-DM74LS123N Datasheet
135Kb / 6P
   Dual Retriggerable One-Shot with Clear and Complementary Outputs
More results

Descrizione simile - DM74LS123NX

Produttore elettroniciIl numero della parteScheda tecnicaSpiegazioni elettronici
logo
Fairchild Semiconductor
DM74123 FAIRCHILD-DM74123 Datasheet
56Kb / 5P
   Dual Retriggerable One-Shot with Clear and Complementary Outputs
logo
National Semiconductor ...
DM54123 NSC-DM54123 Datasheet
130Kb / 6P
   Dual Retriggerable One-Shot with Clear and Complementary Outputs
DM74LS123 NSC-DM74LS123 Datasheet
135Kb / 6P
   Dual Retriggerable One-Shot with Clear and Complementary Outputs
DM74LS221 NSC-DM74LS221 Datasheet
142Kb / 6P
   Dual Non-Retriggerable One-Shot with Clear and Complementary Outputs
logo
Fairchild Semiconductor
DM74LS221 FAIRCHILD-DM74LS221 Datasheet
108Kb / 8P
   Dual Non-Retriggerable One-Shot with Clear and Complementary Outputs
logo
National Semiconductor ...
DM74LS122 NSC-DM74LS122 Datasheet
129Kb / 6P
   DM74LS122 Retriggerable One-Shot with Clear and Complementary Outputs
logo
Fairchild Semiconductor
DM74121 FAIRCHILD-DM74121 Datasheet
69Kb / 5P
   One-Shot with Clear and Complementary Outputs
DM74121 FAIRCHILD-DM74121_01 Datasheet
71Kb / 5P
   One-Shot with Clear and Complementary Outputs
logo
National Semiconductor ...
54121 NSC-54121 Datasheet
128Kb / 6P
   One-Shot with Clear and Complementary Outputs
54123 NSC-54123 Datasheet
157Kb / 4P
   DUAL RETRIGGERABLE ONE-SHOP WITH CLEAR AND COMPLEMENTARY OUTPUTS
More results


Html Pages

1 2 3 4 5 6 7 8


Scheda tecnica Scarica

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEETIT.COM
Lei ha avuto il aiuto da alldatasheet?  [ DONATE ] 

Di alldatasheet   |   Richest di pubblicita   |   contatti   |   Privacy Policy   |   scambio Link   |   Ricerca produttore
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com