Browsing by Author "Kang, Sheng"

Now showing 1 - 3 of 3

99.4% Peak Audio Signal Recovery Rate and Ultra-Low 0.32dB Matching Error with 10Hz High Resolution Filter Fitting Wearable Aided Speech Compensation System
(2015)
Lin, Yen-Ting
;
Lai, Shin-Chi
;
Chen, Shin-Hao
;
Peng, Shen-Yu
;
Chen, Ke-Horng
to get high sound quality, the proposed adaptive speech compensation (ASC) system fits psychoacoustic curves for individual needs. Moreover, characteristics of the speakers are considered by real-time speaker impedance estimation (RT-SIE) technique. Hence, original signal can be restored for every user with any speakers. ASC system has 99.4% peak original signal recovery rate by predicting and controlling output signal precisely. And the built-in 10Hz high resolution acoustic filter fitting scheme (AFFS) has less than 0.32dB matching error with an over 80dB hearing loss.
A 2.5W Tablet Speaker Delivering 3.2W Pseudo High Power by Psychoacoustic Model Based Adaptive Power Management System
(2014)
Chen, Shin-Hao
;
Peng, Shen-Yu
;
Chen, Ke-Horng
;
Lai, Shin-Chi
;
Kang, Sheng
for a 2.5W speaker in tablets, the proposed adaptive power management (APM) system can deliver a pseudo high power of 3.2W with a +/- 4V supply because it suppresses 0.7W power on tones that may damage a 2.5W speaker and escape the notice of human ears. With z-domain digital signal processing (z-DSP) and psychoacoustic model, high efficient power management and high sound quality can be achieved simultaneously. Conventional automatic gain control (AGC) only has the ability of 0.32W power suppression. Moreover, suppressing power by conventional clipping technique increases total-harmonic-distortion (THD). In contrast, the proposed real-time dynamic loading impedance (RT-DLI) monitoring brings forward a way to solve the problem on speaker damage while keeping low THD during high sound pressure level (SPL). THD in the APM system is slightly higher than that of original sound 1.1dB, comparing to the disadvantage of 8.6dB increasing caused by conventional clipping technique.
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.