Sorin, no mistakes... Oportunity to learn. As you said, you never seen 3 mosfets in the input circuit. You are one of the best techs i know. We all are getting old, i'm 48 this year, you still have a lot to teach us. Greetings from Portugal 🇵🇹
First off I would just like to a bug thanks for all your time and effort you put into making these videos and sharing your knowledge, I've learnt so much more.... Just one thing when it comes to MOSFETs... If the part number ends with an even number then its a channel N and if it ends in an odd number then it's a channel P.
WOW what a fix, very nice video, 3 fets a new one you taught us so dont feel bad this is very good video. All others watch all ads and dont skip to support sorin !
lesson to learn: check for a third mosfet and maybe a fourth who knows 😂even if the datasheet doesn't show it. But seriously why a third mosfet ?! because we can't say this will help the other mosfets to carry more current because it's not parallel 🤔Great job Sorin🎉
Sorin, we are all getting old, and that doesn't mean we can't do what we just do as far as speed. I am on the same page, I noticed more that I overlooked and missed a few things here and there, but in the end, things that other people could not make the repairs or fix the issue finally resolved and got fixed thank you for sharing your valuable information.
I had a very similar case like 4 years ago on a Toshiba, had a shorted cap and mosfet. When cap was removed it worked but wouldn't charge battery, until we figured out one mosfet was damaged too.
Don't be so hard on yourself...There was no voltage on the gate, replacing the BQ Chip was the logical thing to do. A third mosfet could throw off anybody. Your still the Master Blaster and a Very Good Teacher I learn a lot from you.
Thank for this new lesson Sorin, don't worry you are not became older, the experince is a never ending story, bye Francesco Timpano from Florence Italy
My company bought 10 of these.... in 3 months 6 of them went back for charging issues . Where is the old Toshiba that it was working for 20 years ? Also very lucky connecting ssd with battery and charger already connected to power 😊😊
@@maklogetrich2378 Toshiba and Sharp (both Japanese) currently belong to Mitsui, that is the reason for the design of their circuits today (Chinese technology models).
We cannot, under any circumstances, dispute your expertise. This is our great Sorin, and we are very grateful. Thank you again. btw: Don't be too hard on yourself. We're all human.
Thank you for this video Sorin, thanks to you I learned a lot and now I know that I can expect up to 3 mosfets in the circuit. Don't think only those who do nothing. Regards
hi sorin how are you ? i want to appreciate you and your channel about the very good content that you presenting to us i learned a lot form you how to diagnose the faults and the way to fix it many thanks i wish you all the best
Hey Sorin, keep going no matter what. Although I noticed you mistaken N-channel and P-channel mosfets pretty often over 6 year period of your videos. No offence. All I learned about laptops is Thank to you. Informative video about N-channel and P-channel mosfets, how to identify them in circuits , whether they are basically a wire OR they are conductive only in one way as long as there is a diode inside mosfet, would be helpfull and resolve this foggy topic once for all. Wish you all the best.
Hi Sorin, what seems useless for you might be useful for us. My experience; when I post a video witch seems not very instructive for me, actually it goes viral and I'm getting lot of comments on it. Keep in mind; you're on one side of a "current sensor" and we are on the other side. We're not charing the same point of view. Cheers
Channel P still outputs voltage if voltage on gate is zero. Because it needs less voltage on gate compare to source so technically zero is still less then source. It only cut down voltage if gate voltage is equal or more then source.
"DC3905" is a terrible choice for SMD marking. Immediately I thought it might be a 1N3905 PNP BJT in a strange package. Then I google suggests LP/LT-3905 DC-DC converter. Only after some more searching, I found out about PDC3905T P-Channel MOSFET. It's silly to choose an SMD marking indicating the same name as existing, incredibly popular, parts.
I cant answer the reason or technical why but those mosfets must have 25v at the gate so when checking your dc-in power or ' follow the truck ' what a great analogy.. 🙂
i clearly forgot why or to my understanding reading it to the internet it goes something like this, when using an N channel mosfet usually the load side or something will consume power should be in front/before the N mosfet so the voltage on the gate should only be 5v but usually in laptops the load comes after as it is use as a input mosfet so thats why the inverse voltage or higher is used.
@@ChupoCro yes, thats right, but would it make sense, to use them in a System, where the Voltage is lower? So you always would need an extra switching supply, which raises the voltage, to operate them
Also at 13.11 when probing bq chip you push some solder from pin 6 to 5, at 13.41 it is visible (possible short) , but after you replaced the third mosfet, probably because of the heat, that solder from pin 6 to 5 is not anymore, check at 31.37 time
Someone definitely put a dark spell on this laptop 🧙♂️ And actually you received a warning - check marking on the coil of the charging circuit on 4:08 😅
The Quickest way to check if Mosfet is N or P Channel is by looking at the last number of part number, if its Even number then its N-channel and if its Odd number then its P-channel mosfet eg. 4460 is N-channel 4467 is P-channel. Hope it helps someone out there
Was acting like sorin and checking voltages across ground and fuses. Heard tick! lol! and I think something burned. Now laptop screen has no backlight.
Hello just wondering if you could explain the code printed on the bq chip, the one you removed it BQ 24780S CRF1 whereas the new one you soldered is actually BQ 24780S T1 261 A0ZG.
33:53 - Never connect something while there is power on the board. Disconnect charger, shut down board, then disconnect battery and connect other things. This one move, could make your day a lot worse.
This mosfet was shorted So it was already like a calibrated wire. The reason it didnt work like that was the overcurrent protection from the laptop battery bms.
Hi Sorin there is always three mosfet the one was shorted was batery to sys mosfet. You have always 5 mosfets high, low side , bat to sys mosfet , first and second mosfet. But i do not understand mostly bq 24780s is worjing with n channel mosfets and here P channel mosfet.
The Dynorod laptops arent the same as when Toshiba used to make the Satellite and Satellite Pro lapops - got a lot of them at work and they're quite slow and clunky despite being branded as the Pro range but costing less than £200 so not really a Pro at all.
the motherboard should have a label in big red letters this motherboard uses 3 mosfets HA! i know general electrical and electronics .. I can read schematics and do basic diagnosis... I think if i watch enough of these videos i might actually understand how to do board level repairs.. probably not... but thats what I think.. hehehe thanks for the video
Same laptop, same problem although in my case the mosfet was cooked to the point of falling apart. Some people have commented that even number mosfets are N channel and odd number are P but whilst looking for an equivalent I found that both TPCA 8036-H and TPCA 8039-H are listed as N channel. On that note, I am in Australia and cannot find an 8036 unless I order it from China with a 6 week delivery time frame. I can’t read data sheets to save my life. Can anyone point me at an equivalent or even something with a better current rating?
Actually it is not unique, it is because you like to work without schematics 😅. It is the mosfet that regulates the work from battery whan charger unpluged so that the voltage from battery becomes main power line. It is being made like that for at least 15 years 😅
Hi everyone! Laptop hinges broke, and I used shoe glue. Now the screen is quarter black, quarter grey with lines and half working fine. Anybody have an idea why? The glue was clear and had a strong odor, it took some color of the plastic cover and became blue.
