RF Power Amplifier Frequency Limitation

Hi all,


according to Qorvo's datasheet, this device:

TQP7M9103

works from 500 MHz to 4000 MHz. I have downloaded and simulated the S-parameters, and found that I can still get > 12 dB gain up to nearly 6 GHz. So my question is, what kind of limitations would I expect driving this thing beyond 4 GHz? Is P1dB likely to suffer, and if so, why?

Also, what kind of circuitry is likely to be in the package? I suspect it is just a RF transistor with biasing (a current mirror for example).


thanks,
Aaron

It depends a lot on what components you used in your simulation. Input/Output Return loss is likely to suffer. Noise Figure and/or P1dB is likely to suffer due to Return Loss. It may not be stable (oscillation) far above its intended frequency.

I simulated Gumax and it was more than 10 dB up to 6 GHz, so I'm guessing small signal is going to be ok. My concern is really P1dB/OIP3. Is there any reason to suspect that it would degrade at higher frequencies?

thanks,
Aaron

hi aaron,
why dont you simulate P1dB/OIP3 and decide if it will meet your requirement.

I don't have a model...just s-parameters. I guess you would need x-parameters for something like that.


regards,
Aaron

what simulation software are you using? for keysight ADS, s-parameter will work. you just need to insert formulars to get P1dB..

Are you sure you don't mean x-parameters? If it were at all possible to do with s-parameters, it would only be an estimate, and would have to rely on a lot of assumptions about the device...


regards,
Aaron

s-parameter is small small signal but provided you are operating in linear region, it should give you good estimate. since you have nothing other then s-parameter, its good to simulate it cos you have no other options available!

Hi pragash,

actually I dont have ADS, so I cant simulate it anyway. However, I am honestly very surprised that such a simulation actually exists. Do you have any information on how it works, or what parameters it requires?

Can anybody else confrim that there is a way to simulate p1db in ADS using s-parameters?

Thanks
Aaron

InGaP/GaAs HBT is the package, but your performance is more dependent on your dielectric and layout and impedance matching circuits. Gain and phase shift will be compromised greatly above 4GHz. I am not sure about stability. In any case it is not specified above this so we cannot guess, nor should you expect good results.