Articles
Matching Differential Port Devices
March 9, 2010
•Application Note: Matching Differential Port Devices
Introduction
Differential signaling is the primary choice for a low power RF interconnection because it provides superior immunity to noise by offering twice the signal swing for a given supply voltage. The out of phase property of a balanced pair has several other benefits: it rejects any common mode interference signal, cancels the even order distortions such IM2, and reduces Electromagnetic Interference (EMI), EMI emission, and susceptibility.
However, this presents a challenge for RF designers to integrate differential devices together since the widely used S-parameter matching technique cannot simply be applied. Transmission line design is also different than a single-ended structure because of the differential mode of propagation.
This Application Note depicts a simple generic technique to match differential impedance devices and gives some matching circuit examples for the system shown that uses the SKY65336-11 and SKY65337-11 Front-End Modules (FEMs). The results of differential matching are compared using elaborate tools such as a four-port network analyzer and ADS Electronics Design Automation (EDA) application software.
Click Here To Download:•Application Note: Matching Differential Port Devices
