Easiest way to get +9V from a +18V supply

[Bernardduur]

Ok. What is the easiest way to do this. I have now two pedals into one housing (Fulldrive II and a Hot-tubes) and as I LOVE the Fulldrive on 18V, I dislike the Hottubes on this.

I already tried a normal Vref downgrade of +18V but that did not work.

Someone?

[cd]

7809 regulator.

[Bernardduur]

Wow..... is it that simple?

Just put 18V in the device, out comes 9V......

Wow.

[A.S.P.]

information lost...

[transient]

Not totally sure, but i guess a 9V zener diode could also do the job.

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[Aurin]

Wouldn't the 9V zener diode just start allowing flow @ 9V (As in nothing until you hit 9V then everything after that -- until it burns out of course) ?

[ocelot]

a 7809 regulator is the best way to go add a capacitor to the input say a 100uF

Cheers

[transient]

Wouldn't the 9V zener diode just start allowing flow @ 9V (As in nothing until you hit 9V then everything after that -- until it burns out of course) ?

I remember reading about using zener diodes to drop voltage. I think the zener's supposed to be placed from ground to +18, this way it will limit the voltage to 9V. You also need a resistor before the zener, to limit the current through the zener(as in LEDs).

However this might not be the best approach as you need to lose 9 volts, a zener might not be able to handle that much dissipation.

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[Aurin]

Hrm.... Point... wasn't thinking of it that way --- Like using LEDs to drop 1.6V at a time....  Ah, the follies of being a home-schooled newbie =)

[transient]

Here's a nice zener link:
http://www.allaboutcircuits.com/vol_3/chpt_3/9.html

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