This reference design delivers an envelope-tracking power supply circuit for audio power amplifier (PA) with TPS61088. By adding an audio envelope signal to the FB pin, the TPS61088’s output voltage can change in accordance with the envelope of the audio signal. So the TPS61088 provides a dynamically changing supply voltage to the PA. Thus the PA can always keep high efficiency in the whole output power range.
- 2.7-4.2V input voltage range
- 5.5-11.75V output voltage range
- The output voltage changes linearly with the amplitude of the input audio signal
- Output voltage rise up from 5.5V to 11.75V within 1ms under a full range step up of the audio signal
- Higher efficiency compared to that of the traditional fixed supply PA