Main Converter; Switching Circuit; Main Converter Output Circuit - Panasonic KX-TDA0103XJ Service Manual

8.1.1.2.

Main Converter

This section mainly explains about the operation of main converter circuit which converts PFC output voltage to 41V (TYP.)
output.

1) Switching Circuit

This circuit uses Self-excited Pseudo Resonance Type Converter. This system supplies DC voltage through the following
process: The DC voltage provided from the Rectifier and Smoothing Circuit is converted into RF pulse by switching ON/OFF
MOS FET Q11 repeatedly. While Q11 is switched ON, the energy is charged in the primary of T1, and it will be discharged to
the secondary of T1 while Q11 is OFF.
Constant voltage is controlled by giving feedback to the control circuit from the output through PC601.
The main switch Q11 is controlled by IC2.
Refer to Fig.2 (A), (B).

2) Main Converter Output Circuit

T1 output voltage is rectified by D101, and smoothed by capacitors C104 and C105 (41V TYP.).
Refer to Fig. 2 (C)
KX-TDA0103XJ / KX-TDA0104XJ / KX-TDA0108XJ / KX-TDA0103X / KX-TDA0104X / KX-TDA0108X
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