Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics 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.

RF Choke for DC biasing

Status
Not open for further replies.

ckJJ

Junior Member level 3
Joined
Feb 16, 2005
Messages
27
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,464
For DC biasing for power amplifiers or diode switches, Inductors are often used as RF choke.

How do we decide the value of inductor to use for the RF choke?
 

Choose a value of inductance that gives reactance of about 10 times the impedance at the point you are injecting the bias. This will not disturb teh circuit too much.

As inductance increases, current handling and self resonance frequency decrease. Make sure you are not too close to self resonance at your highest frequency, yet have enough reactance at your lowest frequency.
 

Hi

My feeling is you should use a coil with a SRF which is at least 2 to 3 times the operating freq. Eventually use a small series resistor still if possible.
Or use one of the more broadband beads of course. Everything wat is resonant in the neighbourhood of your operating freq. can be a problem.

rgds
 

Normally using large value of RF choke to increase total impedance
 

ckJJ said:
For DC biasing for power amplifiers or diode switches, Inductors are often used as RF choke.

How do we decide the value of inductor to use for the RF choke?

Read carefully to the end:

**broken link removed**
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top