  Frequency Domain Multiplexed detector arrays constructed of superconducting
Transition Edge Sensors in the current-summing configuration suffer from the
finite impedance of the summing node which should ideally be zero. We suggest
two circuits to alleviate the effect. The first circuit uses a capacitive
resonant transformer to increase the voltages and decrease the currents of TES
signals to overcome the parasitic inductance of the interconnections. On the
SQUID chip impedance transform to the opposite direction takes place. The
second circuit implements a power combiner having a better branch-to-branch
isolation than a simple T-junction. Two SQUID devices have been designed and
fabricated for a proof-of-principle demonstration of the circuits.
