Laptop Model : HP-15-E009TU (TPN-Q118)
Board Number: DA0R62MB6E1.
Fault : Does Not Power On
Repair
Process :
The fault is
that the power-on standby current is 0.065A, and the current after triggering
is 0.226A. The G pole of the isolation Mosfet is measured to be 24.3V, and the
isolation is passed.
Measure the 3
and 5V inductor voltage (the standby voltage of this machine is only available
after triggering). The 3V inductor voltage is 3.3V, which is normal, and the 5V
inductor voltage is 2.23V.
Use an
oscilloscope to measure the voltage output and the voltage output is only about
2V. That means it is not a rear pole puller Low. So I decided to change
the chip. The original chip model was NB669, and the silk screen on the chip
was AEVD.
I couldn't
find the same type of chip, so I changed it to an AEAF chip, but I changed it
several times in succession (the old master's guidance: the way to judge
whether the chip is soldered well is to measure the resistance from the common
point to the inductor, it's OK if it's not connected to ground), and the
voltages are all the same.
The same one. I
measured that the BOOT pin was only 2.2V, and compared with the 3V BOOT pin
which was 4.9V, I thought there was something wrong with the 5V bootstrap
circuit, so I replaced the resistor and capacitor, but the symptoms remained
the same after replacement.
Detected that
the 11th pin VCC was jumping, so i replaced the PC228 capacitor. After the
replacement, pin 11 stopped jumping, but the output was still abnormal. Replace
it with the original AEVD chip and turn it on after triggering.
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