A New Adaptive Drive Voltage Approach for LED Driver

This paper presents a new adaptive voltage drive approach for paralleled LED strings with linear current regulators. The approach employs a voltage pre-regulator with an adaptive output voltage which guarantees the proper operation of LED strings, also has protection method to avoid damage the LED modules in some abnormal situations. Voltage drops across linear current regulators are minimized to achieve maximum efficiency. No feedback wire from linear current regulator is required which simplifies the system design and lowers the total cost.