S9 Operator Board Maintenance Instructions
16
、
DC-DC Circuit
LM27402SQ Voltage Regulator Generation PWM Switching signals drive up and down bridges (Two pairs CMOS
），
and through L2
Inductor Energy Storage, Again by C19
、
C20 Filtering.
LM27402SQ Main function Pin
Pin 7
：
12V Power supply
，
Pin 9, 17
：
GND
，
Pin 2
：
FB Feedback Connection PIC Voltage determined by pin 8 of Pic to decide.
Pin 10
：
Vdd
Pin 13
：
Bootstrap capacitance 10v +
Pin 16
：
Pulse
Pin 12
：
Switching signal
Pin 11
：
Lower Bridge Drive
Pin 14
：
Upper Bridge Drive
DC-DC When the voltage is abnormal
，
First check through the fixture printing information to view PIC is the voltage value DC-DC is the output voltage one to
；
If
there is a disagreement between
，
Please change first LM27402SQ The small capacitance around
；
If DC-DC No output
，
Please check R13
、
R14 Voltages 1v on both sides - R11 Voltage 12V
、
PIC Whether the work is abnormal, PIC Whether the control panel can
be accepted properly I2C Signal.
DC-DC Output voltage Standard
：
14T Operation Board
：
8.3 V-8.6 V
13.5T Operation Board
：
8.4 V-8.7 v
10
