flashing led's

[bruno]

Please help!

I am using a reed switch to generate a pulse from a rotating disc. I want high power led's to flash in time with the rotating disc to freeze the motion.

At the moment the pulse is too long and I would like to shorten it. I thought I could use a monostable 555 timer to do this.

Does anybody have a schematic I could look at?

The pulse is a 5Vdc signal which needs to switch a mosfet

I am stuck!

 

[Hero999]

Yes, use the monostable 555 timer circuit, it'll need to be AC coupled as the pulses last longer than the delay but that's as simple as adding a couple of resistors and a capacitor, see the 555 datasheet for more information.

 

[bruno]

Yes, use the monostable 555 timer circuit, it'll need to be AC coupled as the pulses last longer than the delay but that's as simple as adding a couple of resistors and a capacitor, see the 555 datasheet for more information.

hi. thanks. where can i find the 555 data sheet? i've been using one from the doctronics web page and I keep melting my reed switches!

i must be doing something silly

 

[Hero999]

1) You need to learn how to use Google.

2) The read switch only needs to trigger the 555 timer which shouldn't use much current.

 

[bruno]

1) You need to learn how to use Google.

2) The read switch only needs to trigger the 555 timer which shouldn't use much current.

ok. thanks very much