Panasonic gp8du gph8du th-37px50u th-42pd50u th-42px50u th-42px500u th-50px50u th-50px500u troubleshooting Service Manual

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
The transistor Q5644 monitors the MAIN_3.3V, MAIN_5V, MAIN_9V, and MAIN_2.5V 
lines. If any of these supply voltages becomes excessive, the inline zener diode goes 
into conduction and turn on transistor Q5644. As a result, a voltage drop appears at the 
base of Q5641, causing it to turn on and

 

output a high to pin 111 of the MPU, IC4005, to 

trigger the SOS condition. 
 
 

 

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