Abstract
This article presents a Class-D audio amplifier for capacitive
piezoelectric speaker loads. Employing a dual voltage feedback
(VFB)/current feedback (CFB) topology, the amplifier is capable of
damping
LC
resonance without using an external damping resistor, therefore
reducing system power consumption, cost, and size. Additional power
savings are achieved by using a push–pull (PP)-modulated output stage.
To mitigate linearity degradation due to the mismatch of the feedback
resistors, they are dynamically matched by employing choppers. The
prototype, taped out in a BCD 180-nm process, can drive up to 4
μ
F load with a peak current of 4.4 A while achieving an idle power consumption of 122 mW and a peak THD
+
N of
−
91 dB.
Original language | English |
---|---|
Pages (from-to) | 3726-3735 |
Number of pages | 10 |
Journal | IEEE Journal of Solid-State Circuits |
Volume | 57 |
Issue number | 12 |
DOIs | |
Publication status | Published - 2022 |
Bibliographical note
Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-careOtherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Keywords
- Audio power amplifier
- chopping
- class-D amplifier
- current feedback (CFB)
- piezoelectric speakers
- push–pull (PP) modulation
- resistor-less LC damping