Paper Info
Title
11.6 A 1.46mm<sup>2</sup> Simultaneous Energy-Transferring Single-Inductor Bipolar-Output Converter with a Flying Capacitor for Highly Efficient AMOLED Display in 0.5µm CMOS
Abstract
As the interaction with users becomes more important, AMOLED displays are being more widely used in various electronic devices. As the display is one of the modules that consumes the largest portion of the power in electronic devices, displays must be designed to operate with a higher efficiency to improve a battery longevity. As a means of supplying power to such displays, DC-DC converters and their performance are important. Along with high efficiency, a DC-DC converter should provide quiet supply voltages for the display to avoid light fluctuation [1]. For this reason, many devices use two separate DC-DC converters, boost and inverting buck-boost converters, to generate a positive (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">op</sub> ) and a negative (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</sub> ) output voltage, respectively [2], as shown in top-left of Fig. 11.6.1. Although this structure is advantageous for making quiet output voltages owing to its two-phase operation, it is not cost effective because it uses two inductors. In the single-inductor bipolar-output (SIBO) converter shown in top-right of Fig. 11.6.1, V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">op</sub> and V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</sub> are generated by using one inductor [3]. However, the SIBO converter operates with three phases, the build-up phase, V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">op</sub> transferring phase, and V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</sub> transferring phase, to regulate each output voltage. Therefore, the energy transferring time for each output is shorter than that of the structure in [2]. As a result, its output voltage has a large ripple. The efficiency of a SIBO converter with a flying capacitor increases by reducing the ripple of the inductor current (j <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</sub> ) [4]; however, the energy transferring time for each output is still short. Although each output can be separately controlled to optimize the output voltage ripple [5], the operation is still based on the three phases.
Year
DOI
Venue
2020
10.1109/ISSCC19947.2020.9063141
2020 IEEE International Solid- State Circuits Conference - (ISSCC)
Keywords
DocType
ISSN
CMOS,battery,flying capacitor,energy-transferring single-inductor bipolar-output converter,inverting buck-boost converters,DC-DC converters,electronic devices,AMOLED displays,SIBO converter,size 0.5 mum
Conference
0193-6530
ISBN
Citations 
PageRank 
978-1-7281-3206-8
1
0.40
References 
Authors
3
1
Name
Order
Citations
PageRank
Sung-Wan Hong15012.32