A Chopper Class-D Amplifier for PSRR Improvement Over the Entire Audio Band

The power supply rejection ratio (PSRR) of conventional differential closed-loop Class-D amplifiers is limited by the feedback and input resistor mismatch and finite common-mode rejection ratio (CMRR) of the operational transconductance amplifier (OTA) in the first integrator. This article presents a 14.4-V Class-D amplifier employing...

Chopper PWM-Based Class-D Amplifier

Class-D amplifiers are widely used in audio applications that require a high power efficiency. A high PSRR is beneficial when the power supply contains significant audio band content. Due to mismatches present in the feedback, these can dominate the PSRR of the class-D amplifier, provided the amplifier has sufficient loop gain. No literature has...

A -109.1 dB/-98 dB THD/THD+N Chopper Class-D Amplifier with >83.7 dB PSRR Over the Entire Audio Band

This paper reports a chopper Class-D audio amplifier that obtains high PSRR over the entire audio band. A chopping scheme is proposed to minimize intermodulation distortion between pulse-width modulation (PWM) and chopping in the audio band. A high-voltage chopper is developed to handle a 14.4 V PWM signal. Timing matching techniques are...