Panasonic KX-TDA0103XJ Service Manual page 40

KX-TDA0103XJ / KX-TDA0104XJ / KX-TDA0108XJ / KX-TDA0103X / KX-TDA0104X / KX-TDA0108X
4) 41V Output Voltage
4-1) 41V Output
During normal operation FET Q156 is ON. 41V output is connected to the main converter output, and the regulated output
by the main converter is output. Transformer T301 sub-winding voltage of 15V output converter is led to the voltage gate of
Q156, and Q156 is turned ON.
Refer to Fig. 3-4 (A).
4-2) 41V Output Over Current Protection Circuit
When Over Current flows to 41V output, the potential difference between terminal of R180 occurs causing Q157 to turn ON.
Q156 is OFF because the potential difference between the gate and the source disappears. Consequently the fold back
current limiting shuts down 41V output.
Refer to Fig. 3-4 (B).
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