zuzu
Member level 3
ADS, LPF filter question
Hello friends,
I need a LPF around 850 MHz corner and I found this is quite large as parallel coupled lines so I modified to a 9'th Chebyshev lumped version. Inductors are in 10nH range and caps in 3...10pF and I decided to made inductors on PCB and keep caps ceramics 0805.
I choose for inductors W=10 mils (for Z>100) built from MLIN, MTEE and MSABND and I tune them along with caps for best insertion and return loss. For capacitors I choosed CQ_PAD model from ADS with estimated Q=2000 @ 1 MHz.
LPF looks nice at simulation. Few questions from your ADS experience:
1. When I complete ADS momentum on the same project, results are aberrant. Perhaps momentum ignore my physically existing caps. Any ideas?
2. I haven't found how to set a printed inductor with given (calculated) inductance. I also haven't found a printed inductor without vias I need both legs on the same side and no jumpers.
3. Project will be on ordinary 1.6mm FR4. From your experience, er=4.35 will be close enough? Also I choose after long google study tan loss=0.02.
Thanks in advance,
Hello friends,
I need a LPF around 850 MHz corner and I found this is quite large as parallel coupled lines so I modified to a 9'th Chebyshev lumped version. Inductors are in 10nH range and caps in 3...10pF and I decided to made inductors on PCB and keep caps ceramics 0805.
I choose for inductors W=10 mils (for Z>100) built from MLIN, MTEE and MSABND and I tune them along with caps for best insertion and return loss. For capacitors I choosed CQ_PAD model from ADS with estimated Q=2000 @ 1 MHz.
LPF looks nice at simulation. Few questions from your ADS experience:
1. When I complete ADS momentum on the same project, results are aberrant. Perhaps momentum ignore my physically existing caps. Any ideas?
2. I haven't found how to set a printed inductor with given (calculated) inductance. I also haven't found a printed inductor without vias I need both legs on the same side and no jumpers.
3. Project will be on ordinary 1.6mm FR4. From your experience, er=4.35 will be close enough? Also I choose after long google study tan loss=0.02.
Thanks in advance,