USE OF OPTO-COUPLER OR CURRENT MIRROR TO ELIMINATE LC OUTPUT FILTER EFFECTS IN BUCK-BOOST TOPOLOGY

摘要

The features of a particular configuration of opto-coupler use, in combination with a mere integrator error amplifier, to dynamically eliminate LC filter effects in a DCM Flyback converter application are described. Modeling of error amplifier block in this particular configuration, along with the LC filter integrated modeling of the Flyback converter are used to define and demonstrate the nature of such elimination. The elimination process reduces the system order by two, thus facilitating an output voltage control with very wide bandwidth, while leaving the LC filter function to attenuate switching and higher noise frequencies, alone. The elimination process prevents the peaking effect of LC Filter on the closed loop output impedance, while entailing that the LC Filter components meet certain cost effective criteria for the process validity.