Hi.
I attached ne555 circuit.

I push 2pin switch, There is output on 3pin and stop output.
If I push switch again, ne555 works agian.
But I want to make ne555 work for the first time.

Is it possible??

 

Sorry, I don't understand.

What is 2pin and 3pin?

What do you mean "make ne555 work for the first time"?

What exactly is the purpose of the circuit?

 

Motor control circuits often have a push button switch to turn on and another button switch to turn off. When on, current to a relay coil through the NO contacts keeps them on. The only way to tun them off is to interrupt that current. You could apply that principle to your problem:



Once that relay is activated by the 555, the normally open contacts (NO) will stay closed and the relay energized until you remove or interrupt the the power. There are variations on that design. That is just one.

 

He talks backwards. "2pin" is Pin2 input. "3pin" is Pin3 output.
He probably wants the 555 to work ONLY for the first time.

 

He probably wants the 555 to work ONLY for the first time.

If that's what you want, then remove the connection to pin 7 and connect a small diode (e.g. 1N4148) across the 100kΩ resistor (anode towards pin 6).
Then you will have to momentarily remove the power before the 555 will retrigger.

 

there could be an option that the device will cycle once if the power is turned on and further triggering is done by a button?

 

Hi.
I attached ne555 circuit.

I push 2pin switch, There is output on 3pin and stop output.
If I push switch again, ne555 works agian.
But I want to make ne555 work for the first time.

Is it possible??

Hello,
I think you want it to time out only once no matter how many times the PB is pressed(?).

Here's one way to do that:
The circuit below disables the pushbutton after it is pressed once and timing begins.
You'll need to test on breadboard (I didn't).

eT

 

The circuit below disables the pushbutton after it is pressed once and timing begins.

Yes, I just realized that my simple modification will cause the output to go high whenever the TRIG input is low, even though it won't stay high after the TRIG input goes high, so the trigger input needs to be disabled after the first pulse.
That could also be done with a second 555 used as a latch.

 

Google can translate Korean to ?Chinese or ?Japanese if the immediate to English fails badly
try yourself or post your problem as you spell it in your native . . .

Is it possible??

everything is possible

 

How do you reset your circuit to repeat at a later time
the pulse ?

What is pulse width you want ?


Regards, Dana.

 

Here is a one-time use only circuit.
Press the button and the output goes and stays high.

 

That's equivalent to the mechanical relay.

 

••• if you want the first cycle to be triggered by the event "POWER ON" -- it might occur so simultaneously - because the timing capacitor has no charge and if the internal trigger "boots" to ON state the OUTP will be high until reset by increasing capacitor voltage
if it does not simultaneously "trigger" at startup you should keep the RESET (p4) LOW by RC chain and send a LOW pulse to the TRIGGER (P2) ← the least is done by another startup RC timing chain at the input of extra inverting buffer and the output differentiator + reverse diode to (p2)
, or less certain and more noise prone as below


••• if you want that the TRIGGER (p2) has a response only at the first time it's pressed -- there are variety of ways to implement such . . .
one way is to use RS LATCH and a MOS-Fet that will disable ground from the trigger button after the OUTP (p3) goes high
, etc. ...

 

Here is a one-time use only circuit.
Press the button and the output goes and stays high.

View attachment 197548

Of course thats not a resetable circuit unless one breaks the feedback loop. Or
turns off power.

But clever.


Regards, Dana.

 

Since the TS hasn't been back since his original post, we may be just spinning our wheels.

 

Since the TS hasn't been back since his original post, we may be just spinning our wheels.

i don't have a problem with that . . . if there's nothing to do just start a linear voltage regulator or reference or CC or SMPS design from scratch and see what's coming out of that . . . if you just wait - nothing happens

 

thanks for this information

victor dawson

 

Hi

Please watch my lecture on NE555 timer for basic understanding.

Thanks

 

Hi.
I attached ne555 circuit.

I push 2pin switch, There is output on 3pin and stop output.
If I push switch again, ne555 works agian.
But I want to make ne555 work for the first time.

Is it possible??

Hi

Please watch my lecture on NE555 timer for basic understanding.

Thanks