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This paper proposes a single-inductor bipolar-output (SIBO) switching converter with high efficiency over a wide load range for active matrix organic light-emitting diode (AMOLED) display. The SIBO converter provides a pair of positive and negative output voltages with only one external inductor. The proposed burst mode function can enhance the light load efficiency with low output ripples, 25mV and 10mV for positive and negative voltages, respectively. With the smooth start-up function, the inductor current can rise smoothly and have low peak value, reducing the current stress on inductor and power MOSFETs. The efficiency can be maintained higher than 80% with the load current from 20mA to 140mA. At light loads, the efficiency is higher than 60% when the load current is above 5mA. The maximum efficiency is 88% when the input voltage is 3.7V and the load current is 60mA. [ABSTRACT FROM AUTHOR]

the charge recycling match (CRM) technique is proposed to reduce dynamic power dissipation in display column drivers. The CRM technique can save much power in some polarity operation, which is hard to have charge recycling in conventional techniques. Theoretical analysis and experimental result show maximum dynamic power reduction of 12% and 30% in column inversion panel with R/G/B stripe pixel arrangement and Zigzag panel, respectively. The proposed method is suitable for voltage mode driving scheme and capacitive loading display column driver special in thin-film-transistor (TFT) liquid crystal displays (LCDs) and active mode organic light-emission-diode (AMOLED) display. A complete method application including circuit structure, algorithm and hardware implement are demonstrated in TFT-LCD application. [ABSTRACT FROM AUTHOR]

The paper-like cholesteric liquid crystal display (Ch-LCD) has become the next generation of electronic readers in consuming market. The embedded fully symmetric self-biased switched-capacitor (FSSBSC) with single-inductor high voltage bipolar-output (SIHBO) converter is proposed to achieve the energy and area-efficient driving scheme. As the compact power management module, SIHBO converter can provide +/−35V bipolar outputs for row driving. In addition, the embedded FSSBSC is utilized to generate the different voltage levels for modulating the gray-color in column driving scheme. This combination carries out the effective driving operation for Ch-LCD through the demand of timing control unit. Simulated results show the achievement of +/-35V output voltage in the SIHBO converter and the variety voltage levels generated from FSSBSC. The peak efficiency is derived of 85% with the integrated chip area of 6.53 mm2. [ABSTRACT FROM AUTHOR]

LCD panel with the LED backlight can be controlled by the proposed linear regulation control (LRC) technique for high efficiency and low cost. The LRC technique removes most of the external passive components, which include inductor, E-cap, freewheel diode, and blocking diode. Due to single-stage operation without two-stage power consumption, small volume and high efficiency can be simultaneously ensured. Furthermore, the PLL function can guarantee the line voltage and current to be in phase so as to realize the high power factor (PF) for green power. High efficiency of 85% at 110Vrms and 87% at 220Vrms, high PF of 0.98 at 110Vrms and 0.96 at 220Vrms, and low THD of 18% at 110Vrms and 19% at 220Vrms are achieved. [ABSTRACT FROM AUTHOR]

The article presents a study which proposes liquid-crystal and backlight (LC/BL) algorithm for color-breakup (CBU) suppression in liquid crystal display (LCD). The study revealed that LC/BL algorithm determines the dynamic field-sequential-color (D-FSC) technique needed to reduce the CBU effect without increasing the frame rate. It is concluded that the scope of CBU suppression is more extensive than other conventional FCSs.