Moreover, low

output impedance is able to be realized by increasing amplifier gain.

Active damping with virtual resistance algorithm can effectively suppress resonant peak caused by LCL filters and improve system efficiency [12], which is used to analyse the

output impedance of the grid-connected inverters in this paper.

The common source (CS) and cascode topologies are used at millimeter frequencies._A transistor in common source has low power gain, problems with stability, and low

output impedance. The [C.sub.gd] capacity is like a feedback loop that degrades the insulation and gain.

Performance summary of the proposed VDBA Technology 0.18[micro]m TSMC Supply Voltage [+ or -]200 mV Input Voltage Range -145 mV - +200 mV Power Consumption 6.22 nW Transconductance 64 nA/V Input Impedance (n terminal) 500 G[OMEGA] Input Impedance (p terminal) 877 G[OMEGA]

Output Impedance (z terminal) 5.26 M[OMEGA]

Output Impedance (w terminal) 205 Table 3.

The traditional analysis method is based on a small-signal model, but the model established by the traditional small-signal method is not accurate without considering the coupling relationship between parallel inverters, so this model cannot analyze the influence of the load and the

output impedance of inverter.

Microstrip lines TL4, TL5, and TL6 are used to adjust the electrical length and characteristic impedance so that the actual transistor's

output impedance is close to the ideal

output impedance without packaging.

AC power sources with poor regulation are sometimes called "soft sources." A soft source has a high

output impedance and low peak current capability and cannot provide the peak currents that may be required for stress testing components properly.

Out of these, the filters presented in [11, 20, 21] do not exhibit a low

output impedance and hence fall in the category of noncascadable filters while those in [10, 12, 13, 15] have a low

output impedance and are classified as cascadable filters.

According to our previous paper [5], we obvious that for achieving high

output impedance in high frequencies from the modified Howland current source, which is shown in Fig.2, and by using

output impedance equation expressed by (1), the limited gain and gain-bandwidth of op-amp which is used in its structure must be high.

--to contribute to the impedance adaptation between the detector input and the

output impedance of the preceding stage (which is 50 [ohm]);

At low input power levels, the peak amplifier is cut off because of the class C operating condition The

output impedance [Z.sub.p] of peak cell, should present an open circuit state in theory to prevent power leakage by tuning the offset line [theta]p between peak amplifier and quarter-wave line.

The assumption is validated by the fact that the

output impedance of the transmitter stage of commercially available broadband PLC transceivers is typically low, for example, 3 [ohm] [6].