CC1190 input impedance and matching load

kushal banerjee

Other Parts Discussed in Thread: CC1190, CC1200

If we wanat to simulate the CC1190 impedance network with other components , can we use the impedance information given in the datasheet of the CC1190 ? If not, for what purpose those smith charts are included in the datasheet?

over 7 years ago

0 TER over 7 years ago

TI__Guru**** 317180 points

The smith charts in the datasheet only gives the impedance for the LNA input and the PA input. In addition you would need the impedance of the TR_SW pin.

If you want to see the effect of other components the best is to simulate our reference design (CC1101-CC1190 or CC1120-CC1190) and see the change in S11 and S21 for other components . To get close to the performance stated in the app notes the S11/ S21 should be more or less the same as in the ref design.

What is your goal with the simulation?

0 kushal banerjee over 7 years ago in reply to TER

Prodigy 210 points

I am planning to change the low pass harmonic filter to a bandpass filter using the discrete components only,
and also the matching load has to be derived.

0 TER over 7 years ago in reply to kushal banerjee

TI__Guru**** 317180 points

Why do you want to change it to bandpass?

0 kushal banerjee over 7 years ago in reply to TER

Prodigy 210 points

We want to suppress some spurious emissions coming before our required frequency band, hence we want a bandpass instead of a low pass which can solve our issue.

0 kushal banerjee over 7 years ago in reply to kushal banerjee

Prodigy 210 points

and how can we silmulate your CC1200 and CC1190 combination, do you provide any spice model for that???

0 TER over 7 years ago in reply to kushal banerjee

TI__Guru**** 317180 points

Is this in addition to the recommended SAW filter which is bandpass?

0 kushal banerjee over 7 years ago in reply to TER

Prodigy 210 points

Yes, in addition to the SAW filter,
Actually that SAW filter is working totally fine, but we still need more attenuation at 862 Mhz than what we are getting right now, hence we are planning to make some changes in the low pass and make it a bandpass according to our requirement.

Sub-1 GHz

Sub-1 GHz forum

CC1190 input impedance and matching load