Description Of Block Diagram In Analog Section - Panasonic KX-FP105BX Service Manual

KX-FP101
6.7.

DESCRIPTION OF BLOCK DIAGRAM IN ANALOG SECTION

1. Function
The analog section is composed of the following circuits.
a. Interface circuit to connect with telephone line (NCU)
b. Analog gate array (IC511)
· To change the circuit configuration for Tx/Rx signals of handset, and fax signals.
Following is the detailed description of each circuit.
[NCU]:Network Control Unit
The NCU comprises of the following; DC loop forming circuit to connect with the telephone line; Switching circuit for other
interconnected telephones; Bell detection circuit; Pulse dial generation circuit; Extension phone line off-hook detection circuit;
Sidetone circuit; Remote fax activation circuit. Refer to 6.8. NCU SECTION for the details.
[Analog gate array (IC511)]
The cross-point switch installed in this IC makes it possible to change the circuit configuration for any analog signals such as
the fax signals sent from the digital MODEM board. In addition, this analog gate array integrates a handset circuit, input/output
ports, etc. This IC is controlled by ASIC (IC501) on the digital board.
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