Re: 555 PWM circuit

Ok, I wil try this new design, but can you explain me a little more
why this design is better?

Should I put a resistor between the gate and ground as I said in a
previous post? (discharge the internal capacitor of the transistor)
which value?

Thanks.

On 19 nov, 03:16, "Phil Allison" <philalli...@xxxxxxxxxx> wrote:
"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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