THOMSON 50M14DP Service Manual page 10

3.15 24V‐5V
L116 is the
test point of
U5:RT8110 is a DC‐DC source IC. It had been used in many other boards. It worked as
a model of isochronous BUCK reduction voltage. It separates voltage to setting
outputs voltage by using R130, R111 and R109.When PIN8 of U104 receives the FB
signal; U104 will adjust the square wave's duty ratio of PIN2 and PIN4's outputs. And
it will control the time of two MOS in Q1 so as to stabilize voltage.
Vout=0.8*{1+R130/(R111+R109)}
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