What do you mean by 555 timer

Postby Prayer192 »Fri Oct 30, 2009 7:51 am

so you want the first mode the "monostable operation" right?
if so, then on page 10 you have two pictures first.
the first shows you the switching behavior using a certain example.
the second shows you a diagram that should help you adjust the time.
the straight lines each stand for a potential size of the resistance.
Now you would theoretically only have to take a ruler, look for a desired time (on the left side) and lay the ruler horizontally at the height of the time and where the ruler intersects a straight line go straight down and write down the resistance and the capacitor once and you would be done.

but now we have the problem that your time is too long. now we have several options:
a) you are looking for another building block
b) you enlarge the diagram (it has a linear gradient)
c) you are trying to establish a relationship (a formula) between resistance, time and capacity (you have enough sample values)
d) you simply take the highest time shown (10s) and put in a counter-ic that records the output stiks and switches after x times (your time divided by 10s)

or (the variant I would take) the absolute nerd variant:
e) you quickly acquire the basics of asembler, organize a station for ic programming (available for around 50 €), program your own timer and transfer it to the ic (then you could even use a slightly larger ic who controls everything).