flamingo
Member level 4
Hi, all.
I am now designing the RF front-end for 2.4ghz band, including a LNA and IQ mixers. By using gm-constant biasing for LNA and mixers, there is still about ±1.5 dB variation in voltage gain over -45~85 ° temp variation in a given process corner, and can be up to about ±3dB gain variation for fast-best, typical and slow-worst corners.
fast-best corner is the combination of -45° temp, highest VDD and ff process corner, typical corner is the combination of 45° temp, normal VDD and typ process, while slow-worst corner is the combination of 85° temp, lowest VDD and ss process corner.
My LNA's gain is provided by the product of the gm and LC tuned tank at 2.4ghz, while mixer's gain is also given by gm*R. The gm-constant biasing using on-chip resistors, and there is about ±12% variation over the 3 corners.
Did anyone have senses or experiences in the pvt variations? What is about the typical value of the gain variation for RF front-end? Or, do you have any good ideas to decrease these numbers?
I am now designing the RF front-end for 2.4ghz band, including a LNA and IQ mixers. By using gm-constant biasing for LNA and mixers, there is still about ±1.5 dB variation in voltage gain over -45~85 ° temp variation in a given process corner, and can be up to about ±3dB gain variation for fast-best, typical and slow-worst corners.
fast-best corner is the combination of -45° temp, highest VDD and ff process corner, typical corner is the combination of 45° temp, normal VDD and typ process, while slow-worst corner is the combination of 85° temp, lowest VDD and ss process corner.
My LNA's gain is provided by the product of the gm and LC tuned tank at 2.4ghz, while mixer's gain is also given by gm*R. The gm-constant biasing using on-chip resistors, and there is about ±12% variation over the 3 corners.
Did anyone have senses or experiences in the pvt variations? What is about the typical value of the gain variation for RF front-end? Or, do you have any good ideas to decrease these numbers?