The increasing demand for high-definition audio in mobile platforms is creating the necessity of adequate operation limits for smart amplifiers to safely maximize the power delivered to micro-speakers. The maximum voice-coil temperature (Tmax) is an important parameter for protection algorithms that prevent damage. Standard tests used by micro-speaker suppliers to specify Tmax provide a conservative estimate that depends on the voice-coil materials. Other tests consider the rated noise power, a specification obtained by rigorous lifetime tests. This paper investigates the thermal limits when micro-speakers operate at their specified rated power. These power-based thermal limits are contrasted with values of Tmax specified in datasheets. The evidence found is used to recommend procedures to measure power-based thermal limits that avoid over-protection.
Open
Access
https://www.aes.org/e-lib/browse.cfm?elib=20832
Download Now (876 KB)
This paper is Open Access which means you can download it for free.
Learn more about the AES E-Library
The Engineering Briefs at this Convention were selected on the basis of a submitted synopsis, ensuring that they are of interest to AES members, and are not overly commercial. These briefs have been reproduced from the authors' advance manuscripts, without editing, corrections, or consideration by the Review Board. The AES takes no responsibility for their contents. Paper copies are not available, but any member can freely access these briefs. Members are encouraged to provide comments that enhance their usefulness.
Start a discussion about this paper!
