Output Resistors in P3A amp

[finalanarchy]

Hi guys,

I am building a P3A amp from bits I have laying around, however I only have 0.22ohm resistors not 0.33ohm that is used in the design.

Will I need to change the value of other components to match or should 0.22ohm be fine?

Cheers

 

[JonSnell Electronic]

That should be fine, don't forget when working the quiescent current, the voltage drop will be a different reading than published.

 

[sreten]

Hi,

Nope. Reducing emitter resistors increases optimum bias
current and barely changes the emitter voltage drop.

As it is the P3A is very waffly about optimum bias.

See D.Self regarding alleged CFP optimum bias.

For sure the P3A has Gm doubling @ 50ma to 100ma.

But with such a wide range of bias, 20mA to 100mA,
emitter resistor values don't matter too much at all.

rgds, sreten.