How to match LNA output impedence after adding L-R network?
I designed LNA using AT41411(freq:1GHz),I added L-R network to improve stability(bellow 1GHz),but i do not know how to do output match after adding L-R network as following image.
Anyone can help me?
Thank you in advance.


http://www.circuitsage.com/matching.html
Refer Thomas Lee book THe design of CMOS RFIC for matching the impedances
I mean when i add the stability improving network,how can i use smithchart to match the output impedence for L-R?
go to mwjournal.com ..then to its resources section and view the webinar on impedance matchin
Thanks for your kind reply!But i do not know how to deal with L-R stability network.(the conjugate match load impedence is 87.8+j62.7 if noise match).
Anybody help me?
Hi,
You need to calculate the output equivalent impedance of the circuit.
Then, you identify the real part to 50ohm and cancel the imaginary part.
By this method, you can obtain the value of the L and the R in order to realize the output matching.
Good work.
mariam is right , u need to get the new output impedance of the new circuit , the transistor and the stability network , then all u will do simply design the output matching network in ordinary way
khouly
Thanks for all of reply!
