Audio Loop Back Testing
In mobile phone manufacturing complete audio testing is required for production lines, to quickly check audio interfaces including 3.5mm earphone circuit, speaker, and microphone, to identify defective products before shipment. Previously, manufacturers have used an external audio analyzer which is bulky, expensive, and difficult offers little support for testing program development due to a lack of easy to use SDKs. The system adds time to production by minimal integration with other programs and difficulty in meeting test automation requirements. Alternatively, a sound card can be used in testing, although only for lower audio distortion/noise specifications. The solution can only, however, detect basic audio function, with no simultaneous recording and broadcast functions, affecting consistency and stability of test results and showing relatively high false rates. The lower audio distortion/noise specifications are unable to accurately generate a frequency response curve and distinguish the audio quality differences (good or bad) according to the actual audio performance of mobile phone.