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.

Band-pass filters with lumped elements

Status
Not open for further replies.

srujan1708

Newbie level 4
Joined
Feb 13, 2012
Messages
6
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,318
Are these BPF's (1-1.5GHz, 1.5-2GHz, 2-3GHz and 3-4GHz) realized with lumped elements practically?
 

Are these BPF's (1-1.5GHz, 1.5-2GHz, 2-3GHz and 3-4GHz) realized with lumped elements practically?

Any good filter above ~400 MHz is realized with cavity or stripline resonators. Lumped elements due to skin-effect are too lossy. You can make a high-pass filter or a low-pass filter from pieces of wire but the Q is low, so it is difficult to call it a good filter.

As you can now create active filters above ~1 GHz, maybe some such filters can still use lumped elements with some success.
 
Are these BPF's (1-1.5GHz, 1.5-2GHz, 2-3GHz and 3-4GHz) realized with lumped elements practically?

They can be, in some manufacturing technologies like LTCC. At the frequencies that you mentioned, these are often lumped designs with "printed" spiral inductors and plate capacitors.

But for most "normal" designs/substrates, I agree with jiripolivka.
 

Are these BPF's (1-1.5GHz, 1.5-2GHz, 2-3GHz and 3-4GHz) realized with lumped elements practically?

Often realized commercially using dielectricly-loaded short quarter-wave structures that are capacitively coupled at the tips or the high-E point of the QW resonator; however, scaling components smaller lumped circuits can be fabricated (as others above have pointed out) as in the fabrication of spiral inductors and MIM (Metal Insulator Metal) caps on GaAs wafer and others ... limited BP filters can also be fabbed using 0402 surface mount components up through 4 GHz, but the circuit Q can be lower and one must now pay attention to circuit board 'pads' and any copper 'paths' and vias.

Jim
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top