Patent ID: 6531825
Filing Date: 2003-03-11
Classification: G09G

Abstract:
An apparatus for supplying power to a vacuum fluorescent display (VFD) filament in a vacuum fluorescent display (VFD) unit having a display anode, comprising:a DC power supply unit; a first non-inverting self-oscillating stage coupled to the DC power supply having a self-oscillating stage output node connected to a first terminal of the VFD filament; and a second inverter stage coupled to the DC power supply having an inverter stage input node coupled to the self-oscillating non-inverter stage output node and an inverter stage output node connected to a second terminal of the VFD filament, wherein the self-oscillating stage provides a first output voltage waveform to the first terminal, and wherein the inverter stage provides a second output voltage waveform to the second terminal such that the first output voltage waveform and the second output voltage waveform are anti-phase such that the VFD filament provides a substantially uniform voltage differential profile in relation to the display anode.