Audio signal processors

Details Audio signal processors Audio signal processors

2007-10-23

2007-10-23

Mei, Xu (Department: 2615)

Electrical audio signal processing systems and devices

Including frequency control

Automatic tone control

C381S316000, C381S320000

Reexamination Certificate

active

09600206

ABSTRACT:
An audio signal processor includes a tone control (23). The tone control comprises two low-pass filters (221, 222) operating in current-mode and a subtractor (223) which subtracts the output currents of the filters to produce a band-pass characteristic. Each filter is a tuneable log-domain current-mode filter comprising MOS transistors operating in weak inversion. The tone control is useful in audio signal processors, hearing aids and single-channel and multi-channel Cochlear implants.

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