p1db lna
thanks!
Without having full information about your design I can only recommend increasing the voltage and/or current for your amplifier. If this is impossible, or you want to optimize your deign, please provide more information about the circuit.
supply is 3V,the gain is 24dB, P1db is -12dBm, the structure is 2stage,the load is inductor , each stage is cascode ,the current is about 5mA,when i increase the P1dB, the gain decrease , now the only problem is how to increase P1dB, the design is similiar to maxim2659
Added after 3 minutes:
now the op1dB is 4.8dBm, the p1dB is -18dbm, i think if increase the output power can increase the p1dB, increase the Vod has little effect
What is the frequency band? For frequency band below 1GHz all your spec can be easily done with just one transistor. You are talking about two stages and each is cascode. It looks like over killing. Do you have S-parameter file for your transistors and what are they? What is required NF? Without all information it is hard to help you. If you do not want to openly disclose all the details, but can do it privately, you may send the data to my pm.
sorry , i am a fresher ,the freq is 1.5G ,nf is about 0.8dB,use tsmc0.18 process , what is the sp parameter of transistor, just i see a paper ,it is a single stage ,his power gain is 24dB, p1dB is -13dBm,between the transistor of gm and cascode there is a inductor for interstage matching.the power disspitation can a little larger.
It looks like LNA for GPS. I am not RFIC designer, so I cannot help you with IC based LNA design, my area is lumped elements circuits. But your spec is not very unusual and I think it is not hard to achieve these parameters.
to increase the 1 dB of the Amp u need to use a larger device , which to support higher current and hence higher output power
inductor degeneration is very good to linearize the device and increase the 1 dB compression point but it will sure decrease the gain
Khouly
I Think khouly is right from IC design point of view. But Increasing the current through device will increase the noise as a square of current. It is is not good for LNA.
Do u use any means of interstage matching?
--pap
i have try interstage matching between transconductor transistor and cascode transistor with a inductor ,but still acheive the goal, i think maybe 2stage cant make it because the first stage have gain .
