oscillator circuit

[greg.smith]

Hello,

I was just wondering if anyone knows how to determine the resistor component
values of an oscillator circuit(555 timer IC type), when a pre-determined
frequency is required.

i.e, lets say I want the oscillator to drive some IR LED's at 38
kHz.......how would I determine the resistor values (usually two resistors
in this circuit), and also the capacitor...

gs

 

[[email protected]]

Hello,

I was just wondering if anyone knows how to determine the resistor component
values of an oscillator circuit(555 timer IC type), when a pre-determined
frequency is required.

i.e, lets say I want the oscillator to drive some IR LED's at 38
kHz.......how would I determine the resistor values (usually two resistors
in this circuit), and also the capacitor...

gs

For astable operation:
f = 1/(.693 x C x (R1 + 2 x R2))

See the url:
http://www.uoguelph.ca/~antoon/gadgets/555/555.html

That said, a TV remote control runs at 38 kHz. I suspect
you are experimenting with IR remotes?

 

[DarkMatter]

On Thu, 18 Sep 2003 03:00:39 GMT, [email protected] Gave us:

snip



555 calculator yields over 32,000 hits on google search.