Hey everyone,

First off, let me thank anyone that guides me in advance, as I admittedly have very little experience in what I'm trying to accomplish. I have been using the search function, google, and anything else that I could possibly find to try and get the answer to my question that I haven't been able to figure out. So I ask the more experienced people here at AAC.

I have been trying to find a way to control a small thin fan off of a 1.5v D battery that cycles on for 5 minutes, off for 15. 555 Timers seem to be the way to go, but is there another method?

If I use a 555 timer, do I need a PCB or can i just wire it together?

Do I need a relay, or can I use a transistor?

 

Hi,Hi, If you use a 555 (or more than likely you will need 2, one for on time and one for off time), you will need the low voltage version to run at 1.5volts....The problem that you will have is that it may be dificult getting a relay with a 1.5volt coil and using a transistor to switch the fan will result is a 0.5 to 0.7volt drop accross the device, so your fan will only see a volt or so....Can you maybe use 2 cells to get 3 volts, it will make things a lot easier....Daniel.

 

Would a CMOS 556 work?

And I suppose I could bump it up to 3 volts, but the product that I'm trying to replicate uses 1 d-cell battery and that makes it easier to just wire in a single battery holder with a fair amount of battery life and considerable space savings.

 

Now you have got me there...I am not sure if they make a low voltage version of the 556, but if they do then it would be fine...Daniel.

 

if size is an issue why not use a 9 volt or a watch-sized battery?