Browsing by Author "Ng, Shao Siang"

Now showing 1 - 4 of 4

A 94% Efficiency Near-Constant Frequency Self-Oscillating Class-D Audio Amplifier with Voltage Control Resistor
(2013)
Ng, Shao Siang
;
Lin, Kuei-Liang
;
Chen, Ke-Horng
;
Chen, Yu-Wen
;
電控工程研究所
A self-oscillating constant frequency class-D audio amplifier with voltage control resistor (VCR) technique is proposed for system-on-a-chip (SoC) applications. The VCR control circuit is used to ensure stable switching frequency over a wide range of the modulation index. The proposed method also improves the THD performance at high output power condition. The proposed self-oscillating class-D amplifier can have extremely good performance since the carrier distortion is avoided and the intrinsic harmonic can be attenuated by the second-order loop filter. The VCR control can dynamically adjust the switching frequency according to distinct modulation index. In addition, stable frequency operation can reduce the switching frequency at low output amplitude to improve power efficiency. Experimental results demonstrate that the proposed class-D amplifier can delivers 1.4W to the 8 Omega load with a 5V supply. The power efficiency is achieved over 95% and the output THD can be smaller than 0.001%.
A Class-D Amplifier Powered by Embedded Single-Inductor Bipolar-Output Power Module with Low Common Noise and Dynamic Voltage Boosting Technique
(2014-01-01)
Chen, Shin-Hao
;
Lin, Kuei-Liang
;
Ng, Shao Siang
;
Chen, Ke-Horng
;
Wey, Chin-Long
This paper proposes a high efficiency Class-D amplifier (CDA) with embedded single-inductor bipolar output (SIBO) power module. The characteristics of SIBO converter\'s bipolar outputs not only suppress equivalent common mode noise but also remove several large external bulky components in conventional boost supply CDA systems. Since bipolar outputs in the SIBO provide independent driving capability, CDA is capable of operating in both single-ended (SE) and bridge-tide load (BTL) configurations. Furthermore, the proposed dynamic voltage boosting (DVB) technique adjusts the SIBO output voltage level according to the CDA\'s output level with 5% power efficiency improvement. Peak total harmonic distortion plus noise (THD+N) performance is 0.012%. Peak power efficiency of SIBO and CDA are 89% and 93.2%, respectively.
A Direct AC-DC and DC-DC Cross-Source Energy Harvesting Circuit with Analog Iterating-Based MPPT Technique with 72.5% Conversion Efficiency and 94.6% Tracking Efficiency
(2016-08)
Chen, Shin-Hao
;
Huang, Tzu-Chi
;
Ng, Shao Siang
;
Lin, Kuei-Liang
;
Du, Ming-Jhe
The proposed cross-source energy (CSE) harvesting system accepts universal energy sources, including the ac and dc sources. The buck-boost conversion of CSE automatically converts ac or dc input into dc output without being limited by the type of universal energy source. The CSE technique simultaneously supplies the regulated output for the system loading and the battery charging output. A test chip fabricated in the VIS Bipolar, CMOS, and DMOS (BCD) process can optimally derive harvest energy with 72.5% power efficiency when one solar input source is used. A backup converter is designed to complement the CSE technique to guarantee the regulation of output voltage. The proposed analog iterating-based (AIB) maximum power point tracking (MPPT) technique achieves 94.6% tracking efficiency without complex data calculation and storage, which are better results compared with those of previous research.
Embedded Single-Inductor Bipolar-Output DC-DC Converter in Class-D Amplifier for Low Common Noise
(2016-04-01)
Chen, Shin-Hao
;
Lin, Kuei-Liang
;
Ng, Shao Siang
;
Huang, Tzu-Chi
;
Chen, Ke-Horng
This paper proposes a high efficiency class-D amplifier (CDA) with embedded single-inductor bipolar output (SIBO) power module. The characteristics of SIBO converter\'s bipolar outputs not only suppress equivalent common-mode noise but also remove several large external bulky components in conventional boost supply CDA systems. Since bipolar outputs in the SIBO provide independent driving capability, CDA is capable of operating in both single-ended and bridge-tide load configurations. Furthermore, the proposed dynamic voltage boosting technique adjusts the SIBO output voltage level according to the CDA\'s output level with 5% power efficiency improvement. Peak total harmonic distortion plus noise performance is 0.012%. Peak power efficiency of SIBO and CDA is 89% and 93.2%, respectively.