some links.........

check these links.............

http://www.edn.com/article/CA45962.html?text=speech+recognition

http://books.google.co.in/books?id=hrlRFMh-dgYC&pg=PA40&lpg=PA40&dq=aic23+codec&source=bl&ots=oPml1tOEsM&sig=xNES4r9jm9ZcYw87QWJ9UsRTDvs&hl=en&sa=X&oi=book_result&resnum=8&ct=result#PPA33,M1