Re: 555 PWM circuit


"Vicente"

I've build a PWM control following this design:

http://www.pablin.com.ar/electron/circuito/varios/pwm-cc/index.htm


** Bad circuit for high power PWM use.

The frequency varies with the duty cycle.

This is a much better schem:

http://www.cpemma.co.uk/555pwm.html

But change C1 to 10 nF to raise the frequency and use a 10 amp Schottky
diode for D3.

Paralleled BUZ11s are fine with the old circuit drive component values.



....... Phil


.

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