hi guys, my motherboard will not start no matter what
when connected to ac power, the battery does get charge, led indicator glows red when discharged and turns white as it is fully charged.
but rest nothing happens no sign of life.
this laptop has one preexisting usbc power issue - so i use DCIN jack for charging my laptop.
with this issue my laptop was unable to power ON only sometimes i just had to wait some time.
but now nothing happens no matter how much i wait/ charge/ press and hold power button.
i have no knowledge of motherboards ....
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lenovo flex 5 14itl05 power sequence issue
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no, i was working on metal plate, and there was some movement and the live wire touched the plate and near the soldered joint and back plate of LED (heatsink) made a connection. i think.
R1, R2, L1, and the first LED(only) was blown(open) so i replaced them all only for them be blown again (this time i made sure everything was insulated) maybe something else is shorted too. hope its not the IC.
Can i not use this LED circuit without input filtering. if i am unable to find the right parts....
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i have succesfully blown the input (AC) side of the rectifier.
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LEDs are fine.
this is a bypass capacitor so can i replace it with any higher value for capacitance and rated voltage
the current one on board is 4.7uF and 50V
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LED driver board, orient electric, 7W
[PHP][/PHP]
datasheet= [URL]https://www.alldatasheet.com/datasheet-pdf/pdf/1132452/SISEMIC/SIC9753.html[/URL]
i have tried to make the schematic similar to typical application
A1 = varistor
V_C5 _measured wrt -ve = 57-60V pulsating DC, VDD_measured wrt GND_IC = 12-14, VDD_measured wrt -ve = 60-62V pulsating, V_Drain wrt -ve =309V,[LIST=1][*]L2 is unknown, how to measure inductance with multimeter?[*]what is happening after rectification and varistor? what does this IC do? how does it provide constant current ?[*]R8 36Kohm is to discharge the capacitor C5 100uF only, right?[*]how...
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lenovo flex 5 14ITL05 laptop keyboard cleaning
are there any resources that talk about cleaning keyboards thoroughly, by that i mean removing keycaps and cleaning.
i am worried about breaking those keycaps or the plastic retainer clip.
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lenovo flex5-14itl05, touchpad water damage
last night i dropped some liquid over my laptop touchpad, immediately stopped using and tried to dry it up.
the touchpad misclicks, sometimes stops working altogether
i have removed the touchpad assembly cleaned it with alcohol and brush and cotton buds.
can i fully disassemble the touchpad assembly as i suspect some liquid is still lurking inside the trackpad.[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3309891}[/ATTACH]last night i dropped some...
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help me make sense of this error
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3304944}[/ATTACH]
I am sure the bios chip has the right size 256 mb and the same part number W25R256JVEIQ as in the schematic. i have checked personally.
why does it say 16 mb disk space needed.
help me make sense of this error
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3304944}[/ATTACH]...
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lenovo flex 5 14ITL05
can anyone tell me where is the lid sensor on Flex 5 [B]14ITL05
motherboard info LC56-14T[/B]
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3304409}[/ATTACH]can anyone tell me where is the lid sensor on Flex 5 [B]14ITL05
motherboard info LC56-14T[/B]
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3304409}[/ATTAC...
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lenovo flex 5 14ITL05 bios and motherboard fault
my laptop is lenovo flex 5 [B]14ITL05[/B]
recently my power supply for this laptop developed a fault.
which caused a short in my usb c port -- verified with a new charger.
rant: so, i went to the repair tech in my country, he asked for a huge repair cost when i decided to get it done someplace else this "great person" nicked my bios chip, asked me to be aware for repair scams lol.
I was stupid and unable to find the flaw at the moment. Another repair tech told me that my bios chip was stolen and an 8mb bios chip is in place of that. he told me that...
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[ATTACH=JSON]{"alt":"Click image for larger version Name:\timage.png Views:\t0 Size:\t15.1 KB ID:\t3301603","data-align":"none","data-attachmentid":"3301603","data-size":"full","title":"image.png"}[/ATTACH], Lead Acid Battery
i don't understand this thing in my circuit.
the outer ring LEDs are 56 mA 18V 1W but inner ring LEDs are 167mA 3V 0.5W but they are connected in series as per tracing and schematic.
so what is limiting?
will the LEDs take 56 mA or 167...
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CapLeaker[USER="132583"]CapLeaker[/USER] the leds on outer ring are rated 18V and 1W ie they draw 55.56 mA current, so can I just replace the MLS chip with any other mosfet that can handle/give the the required current?
...
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CapLeaker[USER="132583"]CapLeaker[/USER] , flickering was indistinguishable when it was working fine,
i am thinking of shorting the Mosfet with wire between the Source and Drain.
maybe add a capacitor for good measure between +ve 320 and -ve (gnd).
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made a mistake, due to ripped gate pad from pcb
[ATTACH=JSON]{"alt":"Click image for larger version Name:\timage.png Views:\t0 Size:\t455.7 KB ID:\t3301216","data-align":"none","data-attachmentid":"3301216","data-size":"full","title":"image.png"}[/ATTACH]...
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Rechargable LED circuit 16W 220AC volt
unamed controller ic , one diode bridge
MLS3535A Mosfet (guess), A1sHB mosfet. 12 1W leds, 10 0.5W leds, bunch of resistors, one capacitor, 2 zener diodes
blown MLS3535A, removing and testing shows OL in diode mode all combination tested. (Pin 1, pin2-3-4, pin 5678 connected) after removing this component
without MLS3535A, AC powered, voltage between Pin234 and Pin5678 is 80V DC, 60V AC, and the outer most ring of 12 LED( 1W) glows faintly.
please help diagnose...
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