Motorola Lapdock 500 Battery Repair - Page 1
Forum section: electronics / repair

author: alext
author_rank: Regular Contributor
timestamp: February 23, 2017, 10:20:09 pm
content: heyRecently 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?

author: alext
author_rank: Regular Contributor
timestamp: February 23, 2017, 10:22:01 pm
content: more pic

author: timb
author_rank: Super Contributor
timestamp: February 24, 2017, 11:44:48 pm
content: 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.

author: alext
author_rank: Regular Contributor
timestamp: February 25, 2017, 05:36:26 pm
content: looks like it has a BQ20Z45 controller,does anybody know which other brand use this chipset in its batteries?

author: SeanB
author_rank: Super Contributor
timestamp: February 25, 2017, 06:23:07 pm
content: 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.

author: alext
author_rank: Regular Contributor
timestamp: February 25, 2017, 06:39:44 pm
content: checked the fuse and it is ok

author: alext
author_rank: Regular Contributor
timestamp: February 26, 2017, 01:07:12 pm
content: checked the mainboard and looks like 2 components friedcan you help me identify them?theres the pics:http://imgur.com/a/UXizs

author: Rasz
author_rank: Super Contributor
timestamp: February 26, 2017, 04:20:47 pm
content: not 2, at least 3MSP430 probably management chip is also fried, and that means something passed full battery/supply voltage into 3.3V rail

author: alext
author_rank: Regular Contributor
timestamp: February 26, 2017, 06:24:05 pm
content: why do you think that the msp430 fried too? / what is the 2 fried one? i cant identify them

author: Rasz
author_rank: Super Contributor
timestamp: February 26, 2017, 08:40:28 pm
content: isnt that a big burnt mark right smack in the middle of the chip?

author: alext
author_rank: Regular Contributor
timestamp: February 26, 2017, 08:44:29 pm
content: probably.too small do determine for shure.but what about the another 2 burnt ones?

author: Rasz
author_rank: Super Contributor
timestamp: February 26, 2017, 08:57:26 pm
content: 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

author: alext
author_rank: Regular Contributor
timestamp: February 26, 2017, 09:01:23 pm
content: is there any way to check it?the damage is not obvios.half of it came off easily(might be some contamination)

author: Rasz
author_rank: Super Contributor
timestamp: February 27, 2017, 12:50:05 am
content: download datasheet, identify supply rail, measure resistance to ground on your board

author: alext
author_rank: Regular Contributor
timestamp: March 01, 2017, 10:50:21 pm
content: thanks / any ideas for the 2 other chips?(fets?)

author: alext
author_rank: Regular Contributor
timestamp: March 04, 2017, 07:04:10 pm
content: do you have any ide where to get this msp430f5521 ? i just find different msp430s anywhere / how to identify the other 2 blown fets?

author: Rasz
author_rank: Super Contributor
timestamp: March 04, 2017, 08:43:25 pm
content: I feel there is a language barrier between usyou 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.

author: alext
author_rank: Regular Contributor
timestamp: March 04, 2017, 08:49:05 pm
content: ok third attempthow to identify the -ok,let it be 3- blown parts? ( the microcontroller may be good)

author: Rasz
author_rank: Super Contributor
timestamp: March 04, 2017, 11:28:26 pm
content: clean it with alcohol and take another picture edit: microcontroller

author: alext
author_rank: Regular Contributor
timestamp: March 05, 2017, 07:40:34 am
content: thanks,tried it but the surface of the fet is burnt,cant see the numbers on it

author: Rasz
author_rank: Super Contributor
timestamp: March 05, 2017, 02:17:05 pm
content: clean microcontroller with alcohol and take another picture

author: alext
author_rank: Regular Contributor
timestamp: March 05, 2017, 06:43:29 pm
content: http://imgur.com/a/1kRR5

author: alext
author_rank: Regular Contributor
timestamp: March 05, 2017, 08:45:40 pm
content: yes i know they are the fetsi 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?

author: alext
author_rank: Regular Contributor
timestamp: March 05, 2017, 09:45:14 pm
content: heres the chip after cleaninghttp://imgur.com/a/8ao1d

author: Rasz
author_rank: Super Contributor
timestamp: March 05, 2017, 11:10:30 pm
content: its the other way around, you are wasting everybodys time if microcontroller is fried- you will not be able to replace it