Output Voltage - Panasonic KX-NS500AG Service Manual

KX-NS500AG
3) Latch Circuit
The main converter latch circuit works to prevent output voltage from reaching an abnormally high state.
This circuit uses mainly the latch function of IC1.
When secondary side protection circuit reaches an abnormal state (section 6 protection circuit), the signal is sent to primary side
through PC50.
The main converter latch circuit then works to stop the operation.
To release the latch status, release abnormal state, then switch the AC input OFF and leave for over 60 seconds before restart-
ing AC input again
4.8.

Output voltage

This section describes the operation of the circuit that converts the main converter output to 15V and 41V.
1) 15V Output
1-1) 15V Output Converter Circuit
This separately-excited depressor chopper converter consists mainly of IC202, D204, L201, C209, C210, R212-R214.
Input power supply is 41V output of the Main converter described in section 2.
15V output is supplied by the ON/OFF switching action of IC202, D204 and Smoothing Circuit of L201, C209, C210.
Output voltage is set by the resistance rate of IC202, R212-R214.
Oscillating frequency IC202 is 300kHz(typ).
1-2) 15V Output Overcurrent Protection Circuit
Operation is protected the IC202 internal Overcurrent Protection Circuit.
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