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Re: cascade multiplier



Subject:      Re: cascade multiplier
       Date:  Thu, 24 Apr 1997 13:20:57 +1200
       From: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz>
Organization: Wellington Polytechnic, NZ
         To:  tesla-at-pupman-dot-com


Perhaps a quick note on what is and isn't a flyback would be in 
order....

>   From:  Kenneth Aaron <kennetha-at-geocities-dot-com>
>     To:  Tesla List <tesla-at-pupman-dot-com>

<snip>
> Ok, you've convinced me.
> If I use those circuits that use a flyback for the HV, would they
> work, I've seen the design with 2 2n3055 transistors that drive
> the flyback, this design has been posted somewhere on the list before.
> This circuit could give the HV I need , but what about the waveform,
> this would give AC but in pulses, not sine wave.

A flyback supply stores energy in the core while the transistor is 
on, then releases it when the transistor is off. It is a *mode* of 
operation. The "transformer" is actually a choke or two chokes wound 
on the same core. Output is determined by stored core energy and 
capacitive loading: Estored = 0.5 Lprim x Iprim(pk)^2
Vout = SQRT(Estored/Cout) assuming no loading on the primary during 
the flyback period.

    The pushpull circuit is a real transformer circuit and its output 
is primarily (npi) governed by the turns ratio. This type of circuit
needs some form of current limiting if that is required. 

Malcolm