oscillator circuit

Sep 17, 2003 3 Replies

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))

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

On Thu, 18 Sep 2003 03:00:39 GMT, snipped-for-privacy@bellatlantic.net Gave us:

snip

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

I assume you want this for a canned IR-receiver? In that case remember that most such receivers are not suited for receiving a continuous IR stream: you will have to modulate the IR stream to assure that there is a minimum amount of 'silence'. Check your receivers datasheet for the details.

Wouter van Ooijen

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