Browsing by Author "Su, Chung-Hsin"

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A New Single Inductor Bipolar Multiple Output (SIBMO) Boost Converter using Pulse Frequency Modulation (PFM) Control for OLED Drivers and Optical Transducers
(2015)
Chang, Chun-Kai
;
Su, Chung-Hsin
;
Kao, Yung-Hua
;
Yu, Ming-Hung
;
Sauter, Thilo
This study proposes a single-inductor bipolar multiple-output (SIBMO) boost converter utilizing pulse frequency (PFM) control for organic light-emitting diode (OLED) drivers and optical transducers. The purpose of the converter designed herein is to provide multiple voltage sources with opposite polarities to meet the requirements of various applications such as OLEDs or optical transducers. The bipolar voltage sources are essential for offering alternating driving voltages to extend the lifetime of OLEDs. The converter boosts the input of 2.8 V to two positive and two negative outputs, i.e., +12 V, +6 V, -12 V, and -6 V. Different from the commonly-used pulse width modulation (PWM), the constant on-time (COT) approach is adopted herein with a dynamic charging algorithm to automatically adjust the operating frequency, thus profiting from less circuit complexity, improvement of cross regulation, and high transfer efficiency in unbalanced load cases. The total maximum output power is 320 mW, as the switching frequency varies from 650 kHz to 0 Hz, and the maximum efficiency reaches 83.1% by simulation. The converter was fabricated by TSMC 0.25 mu m 1P3M high voltage CMOS technology for verification.
A New Single Inductor Bipolar Multiple Output (SIBMO) On-Chip Boost Converter Using Ripple-based Constant On-time Control for LCD Drivers
(2014-01-01)
Chang, Chun-Kai
;
Su, Chung-Hsin
;
Chao, Paul C. -P.
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
A constant on-time (COT) single-inductor bipolar multiple-output (SIBMO) on-chip boost converter is proposed for LCD drivers in this study. The converter is designed for biasing some analog and digital circuits fabricated on glass substrates for benefits of extending the life of LCD. These circuits on glass require bipolar high voltages for drive LCDs. The converter boosts the input of 2.8V to two positive outputs and two negative outputs, +12V, +6V,-12V and -6V, respectively. Different from the commonly-used pulse width modulation (PWM), the constant on-time (COT) is adopted herein by a dynamic charging algorithm whose frequency is adapted to the varied output voltage level, thus enjoying the merit of less circuit complexity and a smaller chip area. The COT is in this study further developed to a ripple-based one for achieving applicability even with unbalanced output loads with high efficiency. While total maximum output power is 260mw and the switching frequency varies from 500 kHz to 650 kHz, the maximum efficiency reaches 82.4%. The converter is fabricated by TSMC 0.25 mu m 1P3M high voltage CMOS technology for verification.
A New Single Inductor Bipolar Multiple Output (SIBMO) On-Chip Boost Converter Using Ripple-based Constant On-time Control for LCD Drivers
(2014)
Chang, Chun-Kai
;
Su, Chung-Hsin
;
Chao, Paul C. -P.
;
電機工程學系
;
Department of Electrical and Computer Engineering
A constant on-time (COT) single-inductor bipolar multiple-output (SIBMO) on-chip boost converter is proposed for LCD drivers in this study. The converter is designed for biasing some analog and digital circuits fabricated on glass substrates for benefits of extending the life of LCD. These circuits on glass require bipolar high voltages for drive LCDs. The converter boosts the input of 2.8V to two positive outputs and two negative outputs, + 12V, + 6V, -12V and -6V, respectively. Different from the commonly-used pulse width modulation (PWM), the constant on-time (COT) is adopted herein by a dynamic charging algorithm whose frequency is adapted to the varied output voltage level, thus enjoying the merit of less circuit complexity and a smaller chip area. The COT is in this study further developed to a ripple-based one for achieving applicability even with unbalanced output loads with high efficiency. While total maximum output power is 260mw and the switching frequency varies from 500 kHz to 650 kHz, the maximum efficiency reaches 82.4%. The converter is fabricated by TSMC 0.25 mu m 1P3M high voltage CMOS technology for verification.
A New Small-Sized Pierce Crystal Oscillator Readout with Novel on-Chip All-Digital Temperature Sensing and Compensation
(2014)
Peng, Hsuan-Wen
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Su, Chung-Hsin
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Chao, Paul C. -P.
;
Hsieh, Jing-Wen
;
Chang, Chun-Kai
This paper presents a 16-MHz digital-controlled crystal oscillator and a time-domain temperature sensor design to achieve a high precision temperature-compensated crystal oscillator in a low-power mobile device. The digital-controlled crystal oscillator is based on Pierce topology with two 8-bit switched-capacitor arrays and the temperature of it is measured by time-domain temperature sensor. For noise reduction, the supply voltages of digital-controlled crystal oscillator and time-domain temperature sensor are regulated at 1.2 V by using two on-chip low-dropout regulators. The proposed circuit design has been successfully fabricated by using TSMC 0.18-mu m CMOS process, where the active area is 0.516 mm(2). The measured start-up time of fabricated 8-bit digital-controlled crystal oscillator is about 0.35 ms and the measured phase noise of 1 kHz offset at 25 degrees C is -119.93 dB/Hz. With temperature compensation, the frequency deviation of it is within +/- 0.08 ppm over -40 degrees C to 85 degrees C. The measured effective temperature resolution of time-domain temperature sensor is 0.45 degrees C/LSB and the measured error is within -6.3 degrees C to 7.1 degrees C at 10 Hz conversion rate. The measured current consumption of chip is about 2 mA.