Lately, it is required that the bandwidth of PWM （pulse width modulation） power amplifier is extended. For example, it is in application of the testing power supply of a low frequency immunity examination, or a clas...Lately, it is required that the bandwidth of PWM （pulse width modulation） power amplifier is extended. For example, it is in application of the testing power supply of a low frequency immunity examination, or a class-D amplifier. In this paper, the authors show that the bandwidth of PWM power amplifier can be controller. This controller is implemented on a DSP （digital can be made wider with this controller. extended by using an approximate 2DOF （2-degree-of-freedom） digital signal processor）. It is demonstrated from experiments that the bandwidth展开更多
Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embed...Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embedded in the class-D audio power amplifier. Design results based on the CSMC 0.5μm CMOS process show that the max efficiency is 90%, the PSRR is -75 dB, the power supply voltage range is 2.5-5.5 V, the THD＋N in 1 kHz input frequency is less than 0.20%, the quiescent current in no load is 2.8 mA, and the shutdown current is 0.5 pA, The active area of the class-D audio power amplifier is about 1.47 × 1.52 mm^2. With the good performance, the class-D audio power amplifier can be applied to several audio power systems.展开更多
A digital input class-D audio amplifier with a sixth-order pulse-width modulation （PWM） modulator is presented. This modulator moves the PWM generator into the closed sigma-delta modulator loop. The noise and distor...A digital input class-D audio amplifier with a sixth-order pulse-width modulation （PWM） modulator is presented. This modulator moves the PWM generator into the closed sigma-delta modulator loop. The noise and distortions generated at the PWM generator module are suppressed by the high gain of the forward loop of the sigma-delta modulator. Therefore, at the output of the modulator, a very clean PWM signal is acquired for driving the power stage of the class-D amplifier. A sixth-order modulator is designed to balance the performance and the system clock speed. Fabricated in standard 0.18 μm CMOS technology, this class-D amplifier achieves 110 dB dynamic range, 100 dB signal-to-noise rate, and 0.0056% total harmonic distortion plus noise.展开更多
This paper describes a multimode high-resolution digital pulse width modulator.This modulator,based on a novel hybrid structure,not only has a programmable duty cycle but also realizes phase modulation.A 576 ps pulse ...This paper describes a multimode high-resolution digital pulse width modulator.This modulator,based on a novel hybrid structure,not only has a programmable duty cycle but also realizes phase modulation.A 576 ps pulse resolution is achieved based on a 13.56 MHz switching frequency for near field communication.Fabricated in a SMIC 0.18-μm EEPROM CMOS process,the total area of modulator is only 130×180μm2.Measurement results validate the multi-mode modulation function and high pulse resolution.展开更多
文摘Lately, it is required that the bandwidth of PWM （pulse width modulation） power amplifier is extended. For example, it is in application of the testing power supply of a low frequency immunity examination, or a class-D amplifier. In this paper, the authors show that the bandwidth of PWM power amplifier can be controller. This controller is implemented on a DSP （digital can be made wider with this controller. extended by using an approximate 2DOF （2-degree-of-freedom） digital signal processor）. It is demonstrated from experiments that the bandwidth
基金supported by the National Outstanding Young Scientist Foundation of China (No. 60725415)the National Natural ScienceFoundation of China (No. 60676009)+1 种基金the Doctor Foundation of Ministry of Education (No. 20050701015)the InnovationFunds (No. 07C26226101993).
文摘Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embedded in the class-D audio power amplifier. Design results based on the CSMC 0.5μm CMOS process show that the max efficiency is 90%, the PSRR is -75 dB, the power supply voltage range is 2.5-5.5 V, the THD＋N in 1 kHz input frequency is less than 0.20%, the quiescent current in no load is 2.8 mA, and the shutdown current is 0.5 pA, The active area of the class-D audio power amplifier is about 1.47 × 1.52 mm^2. With the good performance, the class-D audio power amplifier can be applied to several audio power systems.
基金supported by the National High Technology Research and Development Program of China(No.2012AA012301)the National Natural Science Foundation of China(No.61171001)
文摘A digital input class-D audio amplifier with a sixth-order pulse-width modulation （PWM） modulator is presented. This modulator moves the PWM generator into the closed sigma-delta modulator loop. The noise and distortions generated at the PWM generator module are suppressed by the high gain of the forward loop of the sigma-delta modulator. Therefore, at the output of the modulator, a very clean PWM signal is acquired for driving the power stage of the class-D amplifier. A sixth-order modulator is designed to balance the performance and the system clock speed. Fabricated in standard 0.18 μm CMOS technology, this class-D amplifier achieves 110 dB dynamic range, 100 dB signal-to-noise rate, and 0.0056% total harmonic distortion plus noise.
基金Project supported by the Important National Science & Technology Specific Projects(No2009ZX03001-012-03)
文摘This paper describes a multimode high-resolution digital pulse width modulator.This modulator,based on a novel hybrid structure,not only has a programmable duty cycle but also realizes phase modulation.A 576 ps pulse resolution is achieved based on a 13.56 MHz switching frequency for near field communication.Fabricated in a SMIC 0.18-μm EEPROM CMOS process,the total area of modulator is only 130×180μm2.Measurement results validate the multi-mode modulation function and high pulse resolution.
