Design of innovative time-domain microphone readout using Injection Locked Oscillators
Published : 14 March 2021
Nowadays, Voice Activity Detection is a hot research topic. This application needs the design of high linearity, high dynamic ( > 100 dBSpl) and low noise (< 25 dBSpl) microphones putting stringent requirement on both the transducer and the readout electonics. State of the art microphone readouts are based on a classical amplifier and sigma delta conversion. They fulfill the needs in term of dynamic and noise but at the expense of a high power consumption (1 mW) not compliant with mobile applications.
CEA-LETI is currently working on an innovative transducer design that fulfills the needs in terms of dynamic and noise. To go along with the transducer development, CEA-LETI is searching for a PostDoc whose mission will be to study an Ultra Low Power architecture of readout circuits working in the time-domain and based on Injection Locked Oscillators. The post doc work will consist in an architecture study and its evaluation in term of expected performances. In a second time an optimized chip should be designed and fabricated. Evaluation of the solution will be made by a thorough measurement of the test chip.