We present the integration and accuracy and power improved hearing aid system that proposes the triple oscillation-based loops (TOL) technique. Compared with the conventional techniques, the technique replaces the interface capacitors, A/D and D/A convertors with the oscillation-based closed loop and the calibration/operation feedback paths, which are able to enhance the integration of the system and improve the system's accuracy and power performance. Specifically, the technique achieves the only once of the second-order delta-sigma modulation with an integrator and an oscillator. To realize the architecture, the current mode blocks with calibration and successive subtraction are presented on the circuit design. Simulated with a 0.13 μm standard CMOS process in Cadence, with the 16 ohm loudspeaker impedance under the 1 V supply voltage, the input referred DC offset voltage with interface capacitor free is achieved below 2.5 mV; and the signal-to-noise and distortion rate (SNDR) achieves 50 dB@400 mVp-p output voltage. Moreover, the power consumption with no load is maintained within 350 μW.
['Fanyang Li', 'Tao Yin', 'Xiaoyu Wang']
A 1 V INTEGRATION AND ACCURACY AND POWER IMPROVED HEARING AID SYSTEM WITH THE TRIPLE OSCILLATION-BASED LOOPS TECHNIQUE