Lenovo ideapad 5 windows 11 update disable charging circuit?

[bogart219]

That one may work with the 8mm nozzle, the temp you would set to around 400 deg C, depending on the board

You may still have an use for it if you also do hobby electronics

I thought you had a heat gun like the one below, that one is not suitable

I do have one like that too. LOL

Ha, I was practicing on an old board I trying to remove an, what looked like a mosfit, 8pin.I put some flux on the pins and a little solder then used this heat gun.It seemed liked it took for ever at least a couple minutes and then the gun shut off. I even tried turning it on a couple hours later and it still don't work. I'm thinking about this one I found from amazon, it has the air pump like you suggested so it should work a lot better hopefully.


I got another problem. those parts came in from Digikey but they are the wrong ones. I swear I used the link that mom2 provided but I must of screwed it up somehow.
The ones I needed looked like this:


The ones I got looked like this: WTF?


Even that TPS65994 charge controller looked weird too:

although that had different numbers on the end of it that I didn't think mattered, guess it did.

Here the package the mosfets came in:


Here are the numbers off the mosfets from my board again:

SM
3313
PY1A8

Could you help a brother out and tell me what number to use at digikey, aliexpress or what ever you think best. I thank you for your time once more!!!!!!

[mon2]

For the hot air tool, consider one of these:

https://www.mobilesentrix.com/catalo...NIIX&q=hot+air

For the mosfet, the received parts are correct. They are replacement parts that are suitable to replace the original component. You are viewing the cut ESD safe tape packaging. Once you peel away the top clear tape, the part shape will be similar to the part you are attempting to replace. The bottom side pins will also match the style of the original.

[m1ch43lzm]

Those MOSFETs should look like this (i grabbed a dead board i have laying around), different part number but the same package, around 3mm*3mm




I used aluminum foil adhesive tape to shield a plastic keyboard connector on that board

The Quick 861DW is a good option, also look at Atten ST-862D (i have this one), those two are the most widely used by repair shops, Amazon is selling some 861DW knockoffs under random brands (while using the real Quick product images) but can't guarantee they work for long
Noticed they have gone up in price recently, the website mon2 linked has the Quick 861DW at the lowest price at 250usd (around the same it was before)

Took me around 50 seconds with the Atten to remove it, 430 deg. C/airflow 70% (while i was distracted setting and looking at the stopwatch on my phone )

Ha, I was practicing on an old board I trying to remove an, what looked like a mosfit, 8pin.I put some flux on the pins and a little solder then used this heat gun.It seemed liked it took for ever at least a couple minutes and then the gun shut off. I even tried turning it on a couple hours later and it still don't work.

So it broke in 5 minutes , you should return that thing
Even the cheap 858D/8586/878/898/959/etc types (around 30-40usd under different models/brands, with/without a soldering iron in the same unit) would last longer than that
You may ask here for some suggestions on the hot air: https://www.badcaps.net/forum/troubl...es-and-reviews

[bogart219]

For the hot air tool, consider one of these:

https://www.mobilesentrix.com/catalo...NIIX&q=hot+air

For the mosfet, the received parts are correct. They are replacement parts that are suitable to replace the original component. You are viewing the cut ESD safe tape packaging. Once you peel away the top clear tape, the part shape will be similar to the part you are attempting to replace. The bottom side pins will also match the style of the original.

Yikes, I feel like a dumb ash. I peeled one off the tape and it does look like right. I got to get used to this miniature components. Thanks for the info and the link.

[bogart219]

Those MOSFETs should look like this (i grabbed a dead board i have laying around), different part number but the same package, around 3mm*3mm




I used aluminum foil adhesive tape to shield a plastic keyboard connector on that board

The Quick 861DW is a good option, also look at Atten ST-862D (i have this one), those two are the most widely used by repair shops, Amazon is selling some 861DW knockoffs under random brands (while using the real Quick product images) but can't guarantee they work for long
Noticed they have gone up in price recently, the website mon2 linked has the Quick 861DW at the lowest price at 250usd (around the same it was before)

Took me around 50 seconds with the Atten to remove it, 430 deg. C/airflow 70% (while i was distracted setting and looking at the stopwatch on my phone )


So it broke in 5 minutes , you should return that thing
Even the cheap 858D/8586/878/898/959/etc types (around 30-40usd under different models/brands, with/without a soldering iron in the same unit) would last longer than that
You may ask here for some suggestions on the hot air: https://www.badcaps.net/forum/troubl...es-and-reviews

I just ordered the Attn ST-862D off of Amazon. I went with Amazon cause its real easy fro me to return it if something is wrong with it. (Just drop it off at Kohls). I'm going to order some bent nozzles for it though. i'll let you know what happens.
PS: That cheap heat gun I have might of been user error on my part, will play with that.

[bogart219]

Hey guys, good morning. My st-862d is supposed to be here tomorrow so I'm getting reading to change out those mosfets (fingers crossed). Mom, you posted some schematics of a board like mine. I'm thinking about just going ahead and purchase the exact schematics from this guy:
https://laptop-schematics.com/view/14550/. Is this place legit? Not sure about the 82SF label. Do you think that would help out with diagnosing the problem with my laptop? That way I'll have them for the next time something goes wrong plus I'm trying to learn as much as I can about this. What do you think? Thanks!

[bogart219]

Well I replaced those two mosfets, what a pain in the arse. The new ones were a little bigger than the original so it was hard to see exactly where to place it. I got them on, put everything back together and then put power to it. I was still getting 5 volts but now I was getting 6 to 700 milliamps! Oh Oh, not good. I must of shorted something. Took motherboard out of unit again and fired it back up. I got out my thermal camera and seen the charge controller was red hot. I unsoldered the two mosfets I put on, didn't make a difference. I getting some pictures together and will post tomorrow, I'm exhausted now. I was real happy with the Atten 862D and the Andonstar scope. I now have to learn how to use them right. Hope I didn't trash this board. Til tomorrow.

[m1ch43lzm]

The new ones were a little bigger than the original so it was hard to see exactly where to place it.

As long as the S and G pins physically match on the board, and they're not shorted it should be fine, always use flux when soldering
Check for solder bridges on the MOSFETs you replaced, and on the components around them (it's a tight fit)



With both mosfets removed measure resistance to GND at TBT_VSYS (bottom of PF8301-PF8302)

Which chip gets hot? The BQ25710 (PU5301) or the TPS65994 (UU210)?

Take your time, it's a good idea to measure for shorts before powering on and before/after replacing components, also keep practicing on dead/scrap boards, you'll get the hang ot it, laptop boards really absorb a lot of heat

[bogart219]

I believed that those fets i put down seemed ok, doing a diode test on them. They must not of been the problem with the high current.

Bottom of pf8301 and pf8302 to ground = pf8301 & pf8302 both read 47.1 ohms. These are fuses correct?

TPS65994 gets real hot. Five +5VALW pins (11,12,17,25,26) on UU201 all measure 14.4 ohms to ground. Measuring across CU201 & CU206 , both read 14.4 also.

Yes I need practice no doubt. I put Kaption tape all around those mosfets before I heated them. I used gel flux and ended up setting my temp at 400* and air at 60%. Man, you have to be coordinated to hold that heating gun and hold that chip down on the board with tweezers, while watching the screen, crazy. After I put down those new mosfets, I couldn't help but say "perfect" in my Sorin voice LOL. Thank You!

[m1ch43lzm]

Bottom of pf8301 and pf8302 to ground = pf8301 & pf8302 both read 47.1 ohms. These are fuses correct?

Yes, one end of the fuses goes back to the TPS65994
Resistance to me looks very low on that line

TPS65994 gets real hot. Five +5VALW pins (11,12,17,25,26) on UU201 all measure 14.4 ohms to ground. Measuring across CU201 & CU206 , both read 14.4 also.

Resistance on that line also looks too low to me, it should be in the Kohms range i think

I'll wait for mon2 opinion, I suspect that the TPS65994 has died

Also I'm not 100% sure but the suffix on the TPS65994 I think it has to match, it's 2 letters after the name, example: TPS65994AD, TPS65994BF, I read somewhere on the TI forums that those parts have an internal ROM and they release "updated" chips (denoted by the suffix) according to changes on the USB spec, but can be "patched"

https://e2e.ti.com/support/power-man...eprom-firmware

TPS6599x are ROM-based parts. There is a way to 'patch' the ROMs but it is space-limited. Whenever we run out of space on a part, we 'spin' it. So the spins get the TPS6599xYY portion. Each spin in order of release is AC, AD, AE, BF, BG, BH, BI.

TPS65994AD is very old and cannot support the current USB-PD spec. It has been recommended for customers who are currently developing Intel REference Designs to use the TPS66994 device as this is all Flash-based and will be supported for many years. The ROM parts do drop out of support because the USB-PD spec changes every 6months and we have to be compliant to that. 6 month changes + limited ROM patch space causes many spins and eventual EoL

[bogart219]

The rest of the numbers on that TPS65994 are : TI 218 G2 A9D6 G4. I ordered another one from digikey when I ordered the mosfets but Mon2 said those have to be programmed. Is that something I can do if i get one of those inexpensive programming boards?
Do you think I screwed that chip up, well yeah it was something I did cause it wasn't drawing 6-700 milliamps before I changed those mosfets out. I thought maybe one of those caps was shorted causing those readings on the TPS65994. Hopefully Mon2 has an idea. Thanks!

[bogart219]

I got readings on those fuses going to ground. This doesn't seem right.wonder what happened?

[m1ch43lzm]

After those fuses, according to the boardview it goes to both PL8301 and PL8302, and back to UU201 (TPS65994) pin 3, TBT_VSYS
After both PL8301, PL8302 (CHARGER_IN) it goes to the input of the BQ charger through PR8301


You can remove both PL8301 and PL8302 (you can move them so they make contact with only one pad on the board, that way you won't lose them) to isolate which side is shorted, if it's the TPS65994 or the BQ25710

[bogart219]

After those fuses, according to the boardview it goes to both PL8301 and PL8302, and back to UU201 (TPS65994) pin 3, TBT_VSYS
After both PL8301, PL8302 (CHARGER_IN) it goes to the input of the BQ charger through PR8301


You can remove both PL8301 and PL8302 (you can move them so they make contact with only one pad on the board, that way you won't lose them) to isolate which side is shorted, if it's the TPS65994 or the BQ25710

I will study on this and get back to you! Thanks!

[m1ch43lzm]

Measure resistance to GND at the main rail (labeled 20VB+, but it's the main battery voltage) at PJ6202 (it's a solder blob), should be in the Kohm range or more, don't want a short there
Also, measure resistance to GND at the S (1-2-3) of both PQ8302 and PQ8303, that's the input from each USB-C port, that also goes to the TPS65994, you should have several Kohms or more

I want to confirm if the short is on the TPS65994 side, by removing PL8301 and PL8302 the input to the BQ charger gets isolated

The components in green marked with @ may not be present on the board

[bogart219]

Good morning

I'm getting 48 ohms to ground on both sides of PL8301 & PL8302.
PJ6202 = 3.1 M ohms
PQ8302 = S to ground 6.3 K ohms ( with chip removed).
PQ8303 = S to ground 14.6 ohms

Do you want me to remove those inductors, PL8301 & PL8302?

[mon2]

Yes, to isolate the power rail.

Which side is partially shorted?

[bogart219]

Yes, to isolate the power rail.

Which side is partially shorted?

With both inductors removed, one side of PL8302 reads 43 ohms.

[mon2]

Which side?

[bogart219]

With power adapter hooked up with USB tester, still pulling 6 to 700 milliamps!! Weird!