Hello everyone, can somebody with cascode amplifier

[michael1978]

Hello evervone can somebody help me, to calculate the cascade amplifier,

if somebody can tell me the formula? of to explain me? i am reading the book "electronics devices circuit and theory" page 201-202
i don't know how come the value 2.50v, 1.25v, 1,87v see the photo down...

 

[berkeman]

I fixed your thread title to "cascode" amplifier, which I think is what you are asking about, right?

You should put the ground symbol at the bottom of your schematic so your bias voltages make more sense. And are you meaning to put the AC input signal into the base of Q2 and take the output at the collector of Q1?

 

[berkeman]

Also, for a cascode amplifier, you would typically use a decoupling capacitor on the base of Q1. Is anything like that shown in your book?

 

[berkeman]

Like this:

http://www.daycounter.com/Calculators/Cascode/Cascode-Amp.gif

 

[michael1978]

Thanks anbbody, i made some bad calculations, now i undterstand...
so i fixed...
thanks to anybody for timeee.

greetings.