[sdiy] square2sine/continuos

[harry]

Hi Ragozzino...

Y'know that the voltage across the capacitor of the 555 is a sawtooth wave...
the best way to get a triangle would be to buffer that (with an opamp voltage
follower, or maybe J-FET)... then rectify it around a 1/2 Vdd reference.  This

could be as simple as a one transistor circuit...

This might be the best way... the sawtooth amplitude is always from 1/3 to 2/3

Vdd and will not vary.

Any filter you try will need to be tuned with the oscillator, not easy.

H^) harry

Ragozzino Pasquale wrote:

> i need to convert a 555 squarewave to sinewave, but since someone told me
> it is very hard, and i need to do it with *very* few components, i will be
> happy with any continous waveform (triangle would be great). i know i
> could use a filter to make a sinewave but in my circuit the 555 frequency
> is variable. thanks.

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