Title
Dual Voltage and Current Feedback Class-D Amplifiers with High LC Filter Cut-off Frequency and Nonlinearity Suppression
Author
Fan, Haochun (TU Delft Electrical Engineering, Mathematics and Computer Science)
Contributor
Fan, Q. (mentor)
Zhang, H. (graduation committee) 
Degree granting institution
Delft University of Technology
Programme
Electrical Engineering | Microelectronics
Date
2023-08-25
Abstract
Class-D amplifiers have gained significant importance in automotive applications due to its high efficiency. However, to meet strict electromagnetic interference (EMI) requirements, an LC filter is necessary, which, unfortunately, introduces nonlinearity to the system. This project proposes an architecture by implementing a dual voltage/current feedback loop to suppress the nonlinearity of the LC filter. The voltage feedback is put after the LC filter to suppress its nonlinearity. The current feedback splits the complex poles from the LC filter to stabilize the system.
By implementing current feedback as the inner loop, this design achieves a significant reduction in the LC filter’s bulk and cost in comparison to state-of-the-art, while maintaining a good total harmonic distortion (THD) level of around -110 dB. This architecture is also robust to +/-30% variations in LC filter cut-off frequency. The chip is fabricated using a 180-nm BCD process, with a die size of 3 mm × 2.28 mm.
Subject
Class-D amplifiers
LC filer
current feedback
nonlinearity suppression
THD
To reference this document use:
http://resolver.tudelft.nl/uuid:401a08dd-cc9f-42a9-bd45-6bdbc0a40665
Embargo date
2025-08-17
Part of collection
Student theses
Document type
master thesis
Rights
© 2023 Haochun Fan