CAJ | 학술논문

提出了一种基于0.5 μm 5 V CMOS工艺的低噪声PWM调制 D类音频功率放大器.该放大器在5 V电源电压下以全桥方式可以驱动4 Ω负载输出2.5 W功率;转换效率等于87%,信噪比达94 dB(负载8 Ω,输出功率1 W);THD+N仅0.05%(负载4 Ω,输出功率1 W);PSRR为68 dB(频率1 kHz).分析了整体电路结构及其线性化模型,并着重介绍了高性能前置斩波稳定运算放大器(开环增益117 dB,等效输入噪声16 μV·Hz~(-1/2)),线性三角波振荡电路(斜率偏差仅±0.2%)和功率器件、驱动电路的设计.最后给出了D类放大器的测试结果.
제출료일충기우0.5 μm 5 V CMOS공예적저조성PWM조제 D류음빈공솔방대기.해방대기재5 V전원전압하이전교방식가이구동4 Ω부재수출2.5 W공솔;전환효솔등우87%,신조비체94 dB(부재8 Ω,수출공솔1 W);THD+N부0.05%(부재4 Ω,수출공솔1 W);PSRR위68 dB(빈솔1 kHz).분석료정체전로결구급기선성화모형,병착중개소료고성능전치참파은정운산방대기(개배증익117 dB,등효수입조성16 μV·Hz~(-1/2)),선성삼각파진탕전로(사솔편차부±0.2%)화공솔기건、구동전로적설계.최후급출료D류방대기적측시결과.
A low noise class D audio power amplifier with PWM modulation in 0.5 μm 5 V CMOS process is presented. The amplifier is capable of driving 4 Ω load with an output power of 2.5 W from a 5 V power supply. Its power efficiency is about 87% and its SNR is 94 dB at 8 Ω load and 1 W output power; the THD+N is only 0.05% at 4 Ω load and 1 W output power and the PSRR is about 68 dB at f=1 k Hz. The whole circuit and its linearized model are analyzed. The circuit detail of the high performance chopper-stabilized pre-amplifier with 117 dB open loop gain and 16 μV·Hz-1/2 equivalent input noises, linear triangular waveform generator with ±0.2% slope deviation and power MOSFET device and its drive circuit are also presented. Finally, the experimental results of this work are presented.