Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

PA Bias(ClassAB) need help?

Status
Not open for further replies.

TerryADS

Full Member level 2
Joined
Oct 31, 2008
Messages
133
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,298
Location
USA
Activity points
2,066
Hi friends,
I am a newbie,and want to design PA.I have a question how to select the Bias as following requirement:
RF Output Power: 50 W PEP(Peak envelope power )
Input Drive Level : 1 W
Output Load (RL): 50 Ω
Efficiency (η) > 50%
Bias Voltage: 28 V
Device: MRF9045M

I use ADS to sweep DC curve,there are many selection(IDS) with different Vgs.How to select quiescent point to get 50W PEP?Any formula?

Thanks,
 

ChaoFan

Full Member level 2
Joined
Dec 14, 2004
Messages
128
Helped
7
Reputation
14
Reaction score
4
Trophy points
1,298
Location
China
Activity points
757
PA Bias selection need help?

I think it's better to choose Vdd=28V, Idq=0.2A or 0.3A. What is your average power?
 

    TerryADS

    points: 2
    Helpful Answer Positive Rating

TerryADS

Full Member level 2
Joined
Oct 31, 2008
Messages
133
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,298
Location
USA
Activity points
2,066
PA Bias selection need help?

No AM-modulation at least 47dBm.And as the photo,The rough prediction of P1dB is less than 50W.Then how to select the Q point?(I use Class AB PA)
 

TerryADS

Full Member level 2
Joined
Oct 31, 2008
Messages
133
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,298
Location
USA
Activity points
2,066
PA Bias selection need help?

Anybody can help me?
 

TerryADS

Full Member level 2
Joined
Oct 31, 2008
Messages
133
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,298
Location
USA
Activity points
2,066
Whether do i present it clearly?I mean if i want to get the 50W PEP@1W input,28VDS,which Ids i can select to reach the SPEC.(of course think of linearity)?How to select?
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top