LTC6431-20 S-Parameters Correct File Confirmation?

Question

Hi, 
 I would like to confirm S-parameter files provided for LTC6431-20 are correct. I see mention of port 3 in the header which does not make sense to me for this amplifier, and I also notice the data goes up to 5GHz which is well beyond the rated operation for the part which makes me think something is not correct. I am not sure what "SOLT2" in the header refers to either. 
 
 Can someone please confirm if the S-parameter file linked below is correct, or if not provide correct S-parameter file? 
 
 I am referencing S-parameter file here: 
 https://www.analog.com/en/products/ltc6431-20.html 
 https://www.analog.com/media/en/simulation-models/s-parameters/LTC6431_20_SPARs_25C.S2P 
 
 Below is what I see in header of file. 
 !Agilent Technologies,E5071C,MY46100626,A.10.05 !Date: Tue Dec 10 16:09:51 2013 !Data & Calibration Information: !Freq S11:SOLT2(ON) S31:SOLT2(ON) S13:SOLT2(ON) S33:SOLT2(ON) 
 
 Thanks, 
 Steve

ADIApproved · Accepted Answer

Hi Steve, 
 
 The S Param file does show PORTs 1 and 3. It is still a 2 Port measurement. We have a 4 port network analyzer and just used Port 1 and 3 to make a 2 Port measurement. We show the results far beyond the intended operational range. This is to show that the parts are stable and not oscillating out there. With modern transistors the Ft can be over 50GHz and FMAX of 80GHz it is very important to amke sure the devices are behaving even outside of your intended band. If a device is oscillating outside your band it will still hammer the linearity in band. Few other manufacturers provide this level of info but it is very important. 
 The measurements are based on a SOLT calibration as Hooman has outlined. The measurements are referenced to the package pins. 
 
 Regards, 
 Greg Fung)

ADIApproved · Answer

Hi Steve, 
 
 The S Param file does show PORTs 1 and 3. It is still a 2 Port measurement. We have a 4 port network analyzer and just used Ports 1 and 3 to make a 2 Port measurement. We show the results far beyond the intended operational range. This is to show that the parts are stable and not oscillating out there. With modern transistors the Ft can be over 50GHz and FMAX of 80GHz it is very important to make sure the devices are behaving even outside of your intended band. If a device is oscillating outside your intended band it will still hammer the linearity in band. Few other manufacturers provide this level of info but it is very important. 
 The SPARM measurements are based on a SOLT calibration as Hooman has outlined. The measurements are referenced to the package pins. 
 
 Regards, 
 Greg Fung

Electronic Design Services - PartnerZone

Products In This Thread

LTC6431-20 S-Parameters Correct File Confirmation?

Top Replies