BJT Differential Amplifier

[Tac_T]

anybody can help me with design and characterise a BJT transistor based differential amplifier with a gain of around 20.
please help me as soon possible.

attach the circuit or any suggsestion to me..thanks

 

[Prototyp_V1.0]

This circuit show probably the most simple and functional differential amplifier stage there is.

If the bjt's in current mirrors doesn't match properly, you can always insert a resistor on each resistor emitter.

To get the gain you want, treat the circuit as a opamp and calculate a proper feedback.

 

[LvW]

This circuit show probably the most simple and functional differential amplifier stage there is.

If the bjt's in current mirrors doesn't match properly, you can always insert a resistor on each resistor emitter.

To get the gain you want, treat the circuit as a opamp and calculate a proper feedback.

I think, TAC_T neeeds another circuitry that is even more simple: Replace the current mirror in the collector path by two resistors which can be used to set the gain.
Applying feedback for gain adjustment is not a good recommendation because of the medium range output resistance.

 

[Tac_T]

any idea of significance. materials, procedures, ect to build it?
Thank you

 

[Prototyp_V1.0]

Then I can just throw out some links that should help:

wikipedia.org . . . Differential_amplifier
pdf file explaining

Or just do a seearch for "bjt differential amplifier".

 

[Tac_T]

Thank you for fast reply very

 

[Prototyp_V1.0]

Private message going public:

Hey sorry to pvt msg you, but seem like you the only helping me out. Im a 1st years engineering student. My knowledge not very good with electric stuffs. Its there a different ways to design and characterise a BJT transistor based differential amplifier with a gain of around 20? too the one u gave me?

Thank you very much for all your help

Hi. We take discussion public.

I didn't realize you're first year student so you probably haven't been through op-amp chapters yet. But you DO have done some calculations on differential amplifiers.
I gave you some of the links. There is a LOT of reading on the web. You will find it.

And trust me - when exam time is beyond next corner, you'll be happy that you learned this yourself. If I just calculated those values for you, it would help you nada.