Differential signals and circuits have a magical property: the ability to cancel undesired signals without filtering. In this short (25 minute) webinar we will present:
• The Three Mistakes Everyone Makes When Using Differential Circuits
• How Balanced Circuits Can Give You Better Noise Suppression, Spur Cancellation, and More Power
• The Best Balun to use for Every Situation
What is the difference between the BAL and BALH series?
The BAL series has resistive matching on the output that improves the input return loss the BALH series does not. Read more here: BAL vs. BALH and Microwave Black Magic
Which mixed mode scattering parameters correspond to common mode rejection ratio and other factors?
It is important to define what you want to get out of the common mode rejection ratio (CMRR). Do you want the ratio of insertion loss to common mode signal generation? Or do you want to know what kind of isolation to expect from a mixer? In general the common mode rejection can be expressed as the insertion loss off the common mode to the single ended mode, or S12sc. See more here: Mixed Mode Scattering Parameters: What Are They and How Do I Use Them?
What is the difference between a voltage and current balun? Which type does Marki make?
Read about that here: Current vs. Voltage Baluns
What is the difference between a common mode choke and a balun?
I have to admit I wasn’t familiar with the term, but a common mode choke is a differential in – differential out (a ‘balbal’?) device that has a high insertion loss for common mode signals. Coilcraft has a good writeup on them here, and the operate to surprisingly high frequencies. If you wanted to make such a device to microwave or mm-wave frequencies you could put two baluns back to back, but it would be pretty lossy.
Can you give me any tips on designing and building wirewound baluns? What are the tradeoffs in different topologies (Marchand, Ruthroff, Guanella, etc)?
As a balun company I’d rather not give you any tips on building high frequency type baluns. If you are interested in lower frequency wirewound baluns I recommend Jerry Sevick’s Understanding, Building, and Using Baluns and Ununs. This is a great resource, although it looks like it has gotten pricey since it might be out of print. There are many other article’s in the Ham literature for hobbyists.
Do you have any recommendations for matching from a balun into an ADC?
Yes, contact Rob Reeder at Texas Instruments or Umesh Jayamohan at Analog Devices.