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555 Timer ic question please
Posted: Mon Mar 22, 2021 1:20 am
by sleepypie
Hi guys.
It's been a while since I have used a 555 timer and this should be really easy for you all but I kind of forgot how to use one. The question I have is, in the mono state, when you trigger the timer, will it stay in a state for the time that's set up regardless of if it is re-triggered or will the time restart before timing out? The 555 timer ic I'm used is the LM555 ic from TI, here's the link of this ic's introduction:
https://www.apogeeweb.net/circuitry/LM5 ... sheet.html
Thanks in advance.
Re: 555 Timer ic question please
Posted: Mon Mar 22, 2021 9:21 am
by dyarker
It can be either way. Re-triggerable takes a couple transistors; one to discharge the timing capacitor to start the time over again.
Do you want re-triggerable?
Cheers,
Re: 555 Timer ic question please
Posted: Mon Mar 22, 2021 1:51 pm
by sghioto
The direct answer to your question is YES as long as any additional triggers do not exceed the Delay Time.
Re: 555 Timer ic question please
Posted: Mon Mar 22, 2021 5:59 pm
by dyarker
additional triggers do not exceed the Delay Time
Then the answer is NO. You want additional triggers during the delay ignored till after the delay,
Then another trigger starts a new delay.
"Re-trigger" means the output could stay on forever, as long as triggers happen before the delay time since the previous trigger.
Cheers,
Re: 555 Timer ic question please
Posted: Mon Mar 22, 2021 6:47 pm
by sghioto
dyarker wrote: ↑Mon Mar 22, 2021 5:59 pm
You want additional triggers during the delay ignored till after the delay
Correct. That's what the TS asked, will additional triggers be ignored or extend the Delay time.
Answer:
Yes the triggers will be ignored unless the triggers extend past the Delay time
- NV 555 monostable timing chart.png (4.1 KiB) Viewed 11921 times
Re: 555 Timer ic question please
Posted: Mon Mar 22, 2021 11:10 pm
by dyarker
I asked "Do you want re-triggerable?"
He answered "Yes". Which is wrong based on rest of answer.
"Re-trigger" does
not ignore triggers during time period.
You said the "yes" was to the "Ignore"; but that was not the question!
Please learn to READ before butting in!
Back to post 1 -
regardless of if it is re-triggered
If it is ignoring, then it is
NOT re-triggered, just another trigger occured with no effect. Re-trigger restarts the time period.
So I explained and figured he is a newbie and didn't know yet. What's your excuse?
Thanks,
Re: 555 Timer ic question please
Posted: Tue Mar 23, 2021 7:32 am
by sghioto
dyarker wrote: ↑Mon Mar 22, 2021 11:10 pm
I asked "Do you want re-triggerable?"
He answered "Yes". Which is wrong based on rest of answer.
The TS never responded to your question.
I was responding to the question that the TS asked in post #1
not you.
Please learn to READ before butting in!
Re: 555 Timer ic question please
Posted: Tue Mar 23, 2021 11:31 am
by CeaSaR
sleepypie wrote: ↑Mon Mar 22, 2021 1:20 am
Hi guys.
It's been a while since I have used a 555 timer and this should be really easy for you all but I kind of forgot how to use one. The question I have is, in the mono state, when you trigger the timer, will it stay in a state for the time that's set up regardless of if it is re-triggered or will the time restart before timing out? The 555 timer ic I'm used is the LM555 ic from TI, here's the link of this ic's introduction:
https://www.apogeeweb.net/circuitry/LM5 ... sheet.html
Thanks in advance.
While you are waiting for the above fight to finish, perhaps a bit of reading might help pass the time.
https://www.electronics-tutorials.ws/wa ... timer.html
Dale and Steve, please focus on replying to the help asked. I know this past year has taken it's toll on all of us, but let's not let it permeate a place we've been for so long. Please?
Re: 555 Timer ic question please
Posted: Tue Mar 23, 2021 12:06 pm
by sghioto
CeaSaR wrote: ↑Tue Mar 23, 2021 11:31 am
sleepypie wrote: ↑Mon Mar 22, 2021 1:20 am
Dale and Steve, please focus on replying to the help asked. I know this past year has taken it's toll on all of us, but let's not let it permeate a place we've been for so long. Please?
Agree, it was an honest misunderstanding. I apologize for not quoting the TS when I replied.
SG
Re: 555 Timer ic question please
Posted: Tue Mar 23, 2021 5:38 pm
by dyarker
agreed!
Re: 555 Timer ic question please
Posted: Mon Feb 14, 2022 11:10 pm
by wardrose1
Do you admit that 555 ic is very flammable?
I had to change a lot of ICs for my electrical practice
cookie clicker.