Advanced Balance-Type Electronic Choke for Terminal Devices of Wire Communication System

In most wire communication systems, the communication lines are also utilized as the power lines. In that case, the powered terminals need to separate AC signals and DC supply power. Moreover, the input impedance looking into each terminal from the communication lines should be high because a lot of terminals are connected. Well-known AC/DC separator is constructed by inductors and capacitors. When the lowest frequency of the signal is low, the inductance becomes high and the size of the inductor increases. So, we previously proposed new electronic chokes of unbalance type and balance type. These circuits with small inductors have good characteristics of high input impedance and low loss. In this paper, we propose advanced balance-type electronic choke. It is confirmed by experiments that the better characteristics against both differential-mode input and common-mode input are obtained