This part is a kind of semiconductor called 91214B.

Function of this product has IL91214B.

Manufacturers : IK Semiconductor

Image and pinout :

Some of the text within the PDF file :

TECHNICAL DATA Tone/Pulse Dialer with Handsfree Control and Flash Function IL91214A and IL91214B are tone/pulse dialers designed for providing standard DTMF or pulse signals. The ICs enable to: - generate standard DTMF or pulse signals of dialing as well as “flash” pulses; - store and redial last number; - generate pause in the transmitted package of dial signals; ICs are designed to be used in telephone sets. PIN DESCRIPTION HK MODE IN OSCI 01 02 16 15 R4 R3 R2 R1 C3 C2 C1 DP Pin # A B Designation HK MODE IN Description Hook switch input MODE IN = VDD: pulse mode, 10 Hz, М/В = 1/2, MODE IN = VSS: tone mode, MODE IN = floating mode, 20 Hz, М/В = 1/2 Oscillator input Oscillator output Ground Supply output Tone dialing output Dialing transmission mute ou [ ... ]

91214B PDF Datasheet Download