Analog Devices International Unlimited Company

Yuanyuan Zhao

Xin Yang

Shaoyu Ma

Wenhui Qin

Baoxing Chen

Fang Liu

Micro-scale planar-coil transformers including one or more shields are disclosed. The one or more shields can block most common-mode current from crossing from one side to another side of a transformer. Reduction of common-mode current crossing the transformer results in reduction of dipole radiation, which is the main component of electromagnetic interference (EMI) in some transformers.

Micro-scale planar-coil transformer with shield

Power isolators for providing electrical isolation between an input port and an output port that exhibit low electromagnetic interference (EMI) are described. The low EMI may be achieved by, for example, canceling out a common mode current across a transformer in the power isolator that may be converted into EMI. The power isolator may include at least one oscillator circuit that is configured to apply a first signal to a first transformer and a second, different signal to a second transformer. The first and second signals may be configured such that the common mode current generated in each of the first and second transformers has an opposite direction. Thus, the common mode currents in the first and second transformers may at least partially cancel out. As a result, the EMI exhibited by the power isolator may be reduced.

Growing community of inventors

Reading, MA, United States of America

Yuanyuan Zhao