MVX250i E, MVX200i E, MVX200 ETECHNICAL DESCRIPTION144-4 Audio Signal Flow< AIF >IC801Out ALC (Auto Level Control), fading, and amplification of various output signals. For the beep tone issued at ejection, etc., thesignal from the FR MI-COM is generated in the circuit and changed over in the AIF.The microphone amplifier, HPF, ALC, A/D, D/A, and digital I/F, SPEAKER DRIVER with ALC circuits are contained in this IC.It is also used for changeover between ordinary voice sound and beep sound.< VIC4 >The following processing operations are carried out for reducing noise from the DMC mechanism.• Noise cancellation based on correlation of V-cycle noise components.• Noise component reduction by means of trapping.< Automatic wind noise cutting>For efficient reduction of wind noise, the cutoff frequency of the wind noise cutting HPF circuit is regulated according to thecurrent level of wind noise.Fig. 11SPEAKERDRIVERFRMI-COM.IC801AIF4IC1103DIGIC DVIC2301VIC4IC2000VRP2+−LLRLRRMICHEADPHONEAVJACKB EEPSerialSPEAKERMEM IF CARD IFSDRAM CARDREC/PBHEADFig. 12AIF4 VIC4DIGICDV(L)(R)L + RL − RMICINHPFHPF HPFWINDDETECT(L − R)FRMI-COM.150Hz 600Hz 40Hz 3kHz
