Patent ID: 8035833

Claim:
A communication interface unit of a facsimile, comprising: a MODEM unit to modulate data to be transmitted to an external device and demodulate data received from the external device; a line unit to communicate with the external device through a public switched telephone network including an integrated circuit transmitting the modulated data and receiving the data from the external device for demodulation by accessing the public switched telephone network; and a transformer arranged between the MODEM unit and the line unit to transfer the received data from the line unit to the MODEM unit and transferring the modulated data from the MODEM unit to the line unit, wherein the transformer comprises a ferrite core having a ring shape; a housing to house the ferrite core; and a bonding member to fix the ferrite core to the housing by bonding a part of a circumference of the ferrite core to the housing, wherein the housing comprises a housing unit to house the ferrite core, wherein the housing unit has a trench structure, and wherein the trench structure houses the ferrite core, wherein the size of a surface bonding between the ferrite core and the housing is decided according to an allowable capacitance component on the communication interface unit of the facsimile.