SELF-EXCITED OSCILLATOR CIRCUIT FOR EXCITING PIEZOELECTRIC TRANSFORMER Russian patent published in 2012 - IPC H03B5/00 

FIELD: electric engineering.

SUBSTANCE: invention relates to electronics. To achieve technical result in PT excitation circuit based on feedback loop which includes broadband amplifier, PT with load and feedback loop from PT output to amplifier's input. The above mentioned feedback loop from PT output to amplifier's input PT is represented as a capacitor with one of its terminals being connected with PT output and with the second terminal being coupled with broadband amplifier input. Besides, the effective impedance of broadband amplifier input or load-matching network at its input is below capacitor's impedance and is active so that input signal phase coincides with current phase through the capacitor. The condition of the phase balancing for self-exciting at resonance PT frequency is automatically valid for a wide range of PT parameters change, its load and operation conditions.

EFFECT: reduced sensitivity of piezoelectric transformer excitation at resonance frequency to load volume and characteristics, PT parameters and conditions of operation.

3 cl, 5 dwg