Blinks Sos Circuit - Panasonic TC-L42D2 Technical Manual

4 Blinks SOS Circuit

When the unit is turned on, the DTV source of the P board is provided to the A board for conversion
into other voltages. A zener diode at the base of transistor Q5613 protects against over-current condition.
When the DTV12V source drops to a predetermined level, the zener diode turns off causing Q5613 to
turn off and Q5612 to turn on. The input to IC8001 goes low resulting in the shutdown of the unit and 4
blinks of the power LED.
Slide # 57