Electronics > Beginners
Common emitter push-pull?
<< < (3/4) > >>
JS:

--- Quote from: Hero999 on June 22, 2018, 11:53:41 pm ---Just thinking Q3 will be dissipating a fair amount of power. I'm not sure if it's a good idea to drop that kind of voltage and current, even at 50% duty cycle, so a collector resistor is a good idea: I'd go with 22k.

Another option is to add 100V zener diode and biasing resistor, so Q3 no longer needs to drop such a high voltage.


--- End quote ---
Meh.. You need to drop that energy somewhere, expend your money in a zenner or a bigger tranny, I'd go for the single part.

JS

T3sl4co1l:
OP hasn't mentioned how much current or capacitance drive is required, so it's impossible to say how much drive the transistors also need.

Tim
JS:

--- Quote from: T3sl4co1l on June 23, 2018, 01:16:06 am ---OP hasn't mentioned how much current or capacitance drive is required, so it's impossible to say how much drive the transistors also need.

Tim

--- End quote ---
He used 1k load in the schematics, looks like a lot, 20W to the load but who knows...

JS

TheBaconWizard:
Some seriously fantastic and detailed help here, MANY thanks everyone. I have work to do!
Zero999:

--- Quote from: JS on June 23, 2018, 12:22:31 am ---
--- Quote from: Hero999 on June 22, 2018, 11:53:41 pm ---Just thinking Q3 will be dissipating a fair amount of power. I'm not sure if it's a good idea to drop that kind of voltage and current, even at 50% duty cycle, so a collector resistor is a good idea: I'd go with 22k.

Another option is to add 100V zener diode and biasing resistor, so Q3 no longer needs to drop such a high voltage.


--- End quote ---
Meh.. You need to drop that energy somewhere, expend your money in a zenner or a bigger tranny, I'd go for the single part.

JS

--- End quote ---
I suppose the zener could be replaced with a cheap resistor, but it would still require a high voltage transistor.


--- Quote from: JS on June 23, 2018, 03:07:01 am ---
--- Quote from: T3sl4co1l on June 23, 2018, 01:16:06 am ---OP hasn't mentioned how much current or capacitance drive is required, so it's impossible to say how much drive the transistors also need.

Tim

--- End quote ---
He used 1k load in the schematics, looks like a lot, 20W to the load but who knows...

JS



--- End quote ---
Are you referring to my schematics? I guessed and a 1k load would not dissipate 20W, but 4.9W, since it's capacitively coupled it would get 70V, not 140V.
Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod