LED Current Balance Using a Variable Voltage Regulator with Low Dropout vDS Control

摘要: A cost-effective light-emitting diode (LED) current balance strategy using a variable voltage regulator (VVR) with low dropout vDS control is proposed. This can regulate the multiple metal-oxide-semiconductor field-effect transistors (MOSFETs) of linear regulators (LCR), maintaining on flat vGS-characteristic curves and making all drain currents almost same. Simple group LCRs respectively loaded string LED are employed to implement theme. The VVdc from VVR synthesized by NvD, source vR, specified = VQ. updates instantly, through loop master LCR, which means that slave MOSFETs have same biases their curves. leads being equal each other, producing an even luminance. An experimental setup microchip built verify estimations. Experimental results show luminance LEDs one another, maximum deviation below 1% during wide dimming range, while keeping at voltage, as expected.