Hi Mastertech,
what means "NEZ" ?
First I see this topology in "elektrotechnik, oktober 1983" (Dr. Harms, University Hannover) used for a 25 VA poweramp for +/-350V outputvoltage.
It is a simple circuit to generate high voltages with a minimum of highvoltage n-transitors (or fets).
From there i tried it some years later (as a A/B-amp for +/- 500V) and i find it suffers at high frequencys on a strong asymmetry which stem from the capacitys of the bottom power/control-transistor/fet.
May be for a CLASS-A SPECIALIST and class-a biased and for smaller voltages it is useful!
:
So its good to use high ft-devices.
You can supply the base of the top-darlington from a current-source or bootstrap it.
Because its a transconductance-amp you need strong feedback to get a lo-impedance output so i think you had to add a 2. gainstage. (i used a op-amp)
To hold the voltage before the outputcap stable you need from there also a dc-feedback-path.
Good luck.
Regards
Heinz!
what means "NEZ" ?
First I see this topology in "elektrotechnik, oktober 1983" (Dr. Harms, University Hannover) used for a 25 VA poweramp for +/-350V outputvoltage.
It is a simple circuit to generate high voltages with a minimum of highvoltage n-transitors (or fets).
From there i tried it some years later (as a A/B-amp for +/- 500V) and i find it suffers at high frequencys on a strong asymmetry which stem from the capacitys of the bottom power/control-transistor/fet.
May be for a CLASS-A SPECIALIST and class-a biased and for smaller voltages it is useful!
: So its good to use high ft-devices.
You can supply the base of the top-darlington from a current-source or bootstrap it.
Because its a transconductance-amp you need strong feedback to get a lo-impedance output so i think you had to add a 2. gainstage. (i used a op-amp)
To hold the voltage before the outputcap stable you need from there also a dc-feedback-path.
Good luck.
Regards
Heinz!
Steve Eddy said:
Not Exactly Zen?
Just a guess.
Oh! Duh. It's Zen spelled backward.
se
Ha, thank you!I search for Zen and find it (NP)!
Indeed, the Zen looks very similar, but he has a CONSTANT-currentsource in the top, the Nez-top-currentsource is steering by the bottom-currentsource!
Regards
Heinz!
Hi guys wow the view count is heating up
micheal yes you could add resistors to darlington network if
the circuit is made up from regular transistors, thanks for
your kind suggestion, btw are you German Engineer we get
a lot of them in this thread thats why im asking
thank you all guys i plan to use all of your suggestions in future
versions of Nez
regards
George
micheal yes you could add resistors to darlington network if
the circuit is made up from regular transistors, thanks for
your kind suggestion, btw are you German Engineer we get
a lot of them in this thread thats why im asking
thank you all guys i plan to use all of your suggestions in future
versions of Nez
regards
George
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