EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: alext on February 23, 2017, 10:20:09 pm
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hey :) Recently i bought a used lapdock 500 but the battery seems dead,than after i opened the tape on the back i can measure around 3v on the cells terminals,but on the end of the common wire(to the mainboard) theres 0 v so it seems it is a problem with the battery circuit. what is my options?please give me some advice which component to check and how / does another circuit from a different brand battery might work in it?
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more pic
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:-//
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I have a spare LapDock here with a broken dock connector if you need the battery. I bought it for parts awhile back when I picked up another LapDock for my Raspberry Pi.
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looks like it has a BQ20Z45 controller,does anybody know which other brand use this chipset in its batteries?
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The fuse F is blown, either from there being a short on the battery or from one cell being defective and the controller blowing the fuse to safe the battery.
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checked the fuse and it is ok
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checked the mainboard and looks like 2 components fried |O
can you help me identify them?
theres the pics:
http://imgur.com/a/UXizs (http://imgur.com/a/UXizs)
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not 2, at least 3
MSP430 probably management chip is also fried, and that means something passed full battery/supply voltage into 3.3V rail
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why do you think that the msp430 fried too? / what is the 2 fried one? i cant identify them
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isnt that a big burnt mark right smack in the middle of the chip?
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probably.too small do determine for shure.but what about the another 2 burnt ones?
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doesnt matter at this point, msp430 is a microcontroller, probably managing whole thing. If it got fried half the chips on the board might be fried too (whole 3.3 rail)
the 2 small ones are most likely mosfets
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is there any way to check it?the damage is not obvios.half of it came off easily(might be some contamination)
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download datasheet, identify supply rail, measure resistance to ground on your board
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thanks / any ideas for the 2 other chips?(fets?)
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do you have any ide where to get this msp430f5521 ? i just find different msp430s anywhere / how to identify the other 2 blown fets?
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I feel there is a language barrier between us
you have 3 visibly broken parts, AND multiple non visibly damaged ones. msp430f5521 is a microcontroller, its needs programming, you dont have the firmware.
this is trash, throw it away.
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ok third attempt ;D how to identify the -ok,let it be 3- blown parts? ( the microcontroller may be good)
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clean it with alcohol and take another picture edit: microcontroller
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thanks,tried it but the surface of the fet is burnt,cant see the numbers on it :(
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clean microcontroller with alcohol and take another picture
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http://imgur.com/a/1kRR5 (http://imgur.com/a/1kRR5)
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|O
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yes i know they are the fets :-DD i asked 3 times about them but you just responds to the microchip every time.if i cant get the fets fixed first ,it is pointless to check the microchip or am i get it wrong?
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heres the chip after cleaning
http://imgur.com/a/8ao1d (http://imgur.com/a/8ao1d)
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its the other way around, you are wasting everybodys time if microcontroller is fried- you will not be able to replace it