On-off timer help, please

Thread Starter

Rich B

Joined Jul 26, 2007
3
Good morning,

Please can you help; excuse my ignorance, but I know very little of electronics?

I would like to obtain a battery operated (AAA type or similar) module that turns the power on for roughly 3 seconds then off for a further 3 seconds and repeats this indefinitely. From browsing the internet it seems that I may need something called an astable 555 timer?!?!

Additionally, the complete module must be as small and simple as is possible, ideally not more than 10mm in width and height (length is not so critical, i.e. ideal shape is long and thin). Also, I guess only 2 batteries would fit in my application, so 3v would have to suffice.

Is it possible that this can be made? If any one can do so I'll gladly pay them to provide a couple! Otherwise, can anyone tell me what components I would need to try myself.

Many thanks in advance for your time and any help you can provide, Richard
 

Thread Starter

Rich B

Joined Jul 26, 2007
3
Thanks for your help!

Now load, umm, right then, what exactly is this? Is it the ampage?

Well, to explain, I am taking an battery run motor out of a small childrens toy to use for my little invention. Haven't got the toy to hand presently; however, ampage of an AAA is about 1mA isn't it?

Am I making any sense?

Rich
 

John Luciani

Joined Apr 3, 2007
477
From browsing the internet it seems that I may need something called an astable 555 timer?!?!

Additionally, the complete module must be as small and simple as is possible, ideally not more than 10mm in width and height (length is not so critical, i.e. ideal shape is long and thin). Also, I guess only 2 batteries would fit in my application, so 3v would have to suffice.

Is it possible that this can be made?
Yes. You want the LMC555 timer from National Semiconductor. The LMC555 operates
with a Vcc from 1.5V-5V. To drive your fan you need to buffer the output with a
transistor.

10mm may be a little tight to do with through-hole components but you may
be able to squeeze it in. SMD devices would *easily* fit your packaging.

If you need additional help you can contact be offline (my email address is on
my website).

(* jcl *)
 

bloguetronica

Joined Apr 27, 2007
1,372
Learned one today. I didn't knew that a LMC555 existed. But is is indeed the CMOS version of the LM555. I think there was also an LM7555, if I'm not mistaken.
 

nanovate

Joined May 7, 2007
666
TI's TLC555 is LinCMOS (tm) device which I believe is just a fancy word for CMOS.

They also have SA555 and SE555 timers. Anyway there are some many variants and alternate mfgs it is hard to keep track! That 555 really got around.

John
 

John Luciani

Joined Apr 3, 2007
477
TI's TLC555 is LinCMOS (tm) device which I believe is just a fancy word for CMOS.

They also have SA555 and SE555 timers. Anyway there are some many variants and alternate mfgs it is hard to keep track! That 555 really got around.

John
Here's another one for you --- Zetex ZSCT1555

The Zetex part operates down to 0.9V.

(* jcl *)
 
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