Need Help! A circuit that will produce only 1 pulse

M

menirva

New Member

• Apr 10, 2008

• #1

Hello.. anyone can help me? I'm trying to design a circuit that will only produce a SINGLE PULSE with T_HIGH period.



Or.. how can i make a 74HC390 to reset forever when it reach 0010 state? Because i just need the pulse from 0001 state. In other word, i just need 1 short pulse. This pulse will not be triggered by any other signal.

 

Last edited: Apr 14, 2008

A

Abeer_engjbr

New Member

• Apr 11, 2008

• #2

You can use LM555 timer in Monostable mode to produce one pulse.
See
**broken link removed**

**broken link removed**

Hope that will help.

 

jpanhalt

Well-Known Member

Most Helpful Member

• Apr 11, 2008

• #3

This will produce a single pulse. Its main purpose is a debouncer. It does not give a secondary pulse when the switch opens or is kept closed. Pulse duration is set by C2/R2.

John

 

Attachments

• 555pulse.png

  6.4 KB · Views: 177

Last edited: Apr 11, 2008

M

menirva

New Member

• Apr 14, 2008

• #4

Thanx! The switch can be any oscillator? Can you help me, i tried on p-spice, but i may have done something wrong here?

 

Last edited: Apr 14, 2008

Centretek

New Member

• Apr 15, 2008

• #5

What's wrong with a thyristor?

 

jpanhalt

Well-Known Member

Most Helpful Member

• Apr 15, 2008

• #6

Centretek said:

What's wrong with a thyristor?

Click to expand...

How do you turn it off, if the current is still flowing? You could use a GTO device, but then you still have a circuit about as complicated as the other options.

John