5.9 Checking the DC/DC converter circuit
Checkif the 5Vis output
fromP301 pin1, pin2, pin3, pin4
to I301,I303, I320 pin3.
Checkif the 3.3V, 2.5V
and1.8V line voltage is output
from I301, I302, I303 pin2
OK
FailurePoint
Printedwireisbrokenbetween
P301 pin1, pin2, pin3, pin4 and
I301,I303, I320 pin3.
NG
NG
OK
Failure Point
Printed wire is broken
between I301, I302, I303
pin2,and I314power supply
pin.
Isthe output
FB301being supplied to
I301,I303, I320 pin3?
Failure Point
Printedwireisbroken
betweenI301, I303, I320
pin3 and output of FB301
FailurePoint
I301,I303, I320 is defect ed.
OK NG
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28 5.Troubleshooting (continued)
ACERG24