Abstract—Materials made of metals have their own manifest resonant frequencies. Using this property, the quality test of products from the factory can be performed. An impact is applied to the product and the frequencies of the sound and/or vibration are measured using high-end equipment. They use a general purpose computer or a DSP (Digital Signal Processor)-based stand-alone system which is usually too large in-size to carry and expensive to build. In this paper, we introduce a system that is developed based on a MSP430 MCU (Micro Controller Unit) from TI (Texas Instrument). The ultra-low power MSP430 MCUs make it possible to make a frequency analyzer in a very small size without the need of a large-size battery. The proposed system can be used in situation where the frequency analyzer should be carried easily with an investigator and be built at low cost sacrificing some accuracy. We implemented the system using a Launchpad supplied by TI and could confirm that the proposed system could identify with a relatively high-accuracy the frequencies of various artificial and natural sounds. 
 

Index Terms—ultra-low power MCU, sound, frequency analyzer

Cite: Jaehoon Choi and Yongjoo Chung, "Sound Frequency Detection Using an Ultra-Low Power MCU," International Journal of Electronics and Electrical Engineering, Vol. 5, No. 3, pp. 255-258, June 2017. doi: 10.18178/ijeee.5.3.255-258