how can design class ab power amp

[vahidnoori]

hi every body.
i am beginning in microwave design .i decided to design class AB power amp in ADS . but i don't know how can i make dc biasing to achieve class AB power amp in ads.
is there any body that help me with step by step instruction of design class AB power amp
specially dc biasing of it.

thanks.

 

[chuckey]

1. Select transistor.
2. Get manufacturers data sheet
3. look for "typical applications"
4. copy it and adjust for different frequency.
5. Have a beer.

Frank

 

[vahidnoori]

1. Select transistor.
2. Get manufacturers data sheet
3. look for "typical applications"
4. copy it and adjust for different frequency.
5. Have a beer.

Frank

no i have problem in specify bias point in Id-VDS curve. how can i do? step by step

 

[BradtheRad]

You can put the NPN at top or the PNP at top.

With the PNP at top, you can get both voltage gain and current gain.
Your input signal can be small voltage amplitude, and high input impedance.
Less power is wasted when idling.
Careful adjustment is needed to minimize distortion.



With the NPN at top, you get current gain only.
Your output voltage will be slightly less amplitude than your input signal. Therefore if your input signal is very low amplitude, or high impedance, then it will need pre-amplification.
More power is wasted when idling.

 

[vahidnoori]

yeah .
my problem is on determine the bias point to make A or AB power amp from ID-VDS curve .my circuit and my curve is attached: