Re: I need a switch can you help? IMPORTANT!

Kenneth Carrigan ( (no email) )
Thu, 29 Jan 1998 07:45:56 -0500

I'm sure you'll get lots of answers but here's one that should give real
good/cheep characteristics. Radio Shack IRFZ34 (ask them about
a similar type) - it is a MOSFET with 26 amp capability, the IRLZ34 is
the same but designed for 5 volt gate tuen on levels. The Drain to
Source breakdown voltage is 55Vdc. The turn on ohms is .04ohms.
All you have to do is connect the gate to the 555 output (with a resistor
to V+ supply as required by the 555) and the Source to Ground. The
Drain goes to your load and the V+ goes to the other side of the load.
Now you can control your load upto 55 volts and 26 amps or upto 100
amps short pulse duration.

v/r Ken Carrigan

PS if you use 12 volts or higher on the 555, that's fine for the IRFZ34N
but if less the 12 volts, use the Logic Level MOSFET - IRLZ34N.

>I need a *switching device sometimes called a "chopper" that has low
>resistance that can take more that 1 amp (I really need about 10 amps)
>and an adjustable frequency, I would like a range of at least 50>100hz
>but I am flexible and I really need an adjustable pulse width or one
>that is open about half the time.
>
>This is a very important part of a promising experiment I am trying, If
>you know of a place that makes such a switching device or of a model
>number ot anything please respond, I need a current that seems far to
>high for a 555 circuit or anything that I know like it and so I am
>expecting a rotating switch is what I will find.
>
>If you have any ideas of how I could make one, know were I should look
>or what I should by please respond.
>
>* A component of a circuit that will make and break the circuit so that
>a pulsed DC will result from a constant voltage source.
>
>
>Thank you in advance, John Berry
>
>