This part is a kind of semiconductor called BA6566.

Function of this product has Speech network.

Manufacturers : Rohm

Image and pinout :

Some of the text within the PDF file :

Communication ICs Speech network BA6566 / BA6566F / BA6566FP The BA6566, BA6566F, and BA6566FP are speech network ICs which possess the basic functions required for handset communications. In addition to amplifying signals from a transmitter and sending them to a telephone line, they amplify only reception signals from a telephone line and drive the receiver. They also compensate for fluctuation in the volume at which signals are transmitted and received, caused by the length of the telephone line (AGC). FApplications Telephones and telephone equipment FFeatures 1) Can accommodate both dynamic and piezoelectric receivers, simply by changing the circuit constant for a wide dynamic reception range. 2) Automatic gain control (AGC) is used, based on the transmission and reception telephone li [ ... ]

BA6566 PDF Datasheet Download