![]() |
|
|
Thread Tools | Display Modes |
![]() |
#1 |
Badcaps Veteran
Join Date: Apr 2014
City & State: Coimbra
My Country: Portugal
I'm a: Student Tech
Posts: 305
|
![]() Hi
Long story short, Harman Kardon Aura Studio 2 speaker, no power. Disassembled, found burned IC, maybe the 5V regulator? not sure No schematics IC marking: 225S2 (see pic) Board ref: 40-KS320U-PSK2G Thanks for any help! |
![]() |
![]() |
![]() |
#2 |
Badcaps Veteran
Join Date: Jun 2012
City & State: ☻
My Country: Canada
I'm a: Professional Tech
Posts: 8,161
|
![]() It is a EUTECH EUP3484 buck regulator
|
![]() |
![]() |
![]() |
#3 |
Badcaps Veteran
Join Date: Apr 2014
City & State: Coimbra
My Country: Portugal
I'm a: Student Tech
Posts: 305
|
![]() |
![]() |
![]() |
![]() |
#4 |
Badcaps Veteran
Join Date: Oct 2012
City & State: SG
My Country: SG
Line Voltage: 240v
I'm a: Knowledge Seeker
Posts: 309
|
![]() Dont forget to check the capacitors around as well
![]() |
![]() |
![]() |
![]() |
#5 |
Badcaps Veteran
Join Date: Apr 2014
City & State: Coimbra
My Country: Portugal
I'm a: Student Tech
Posts: 305
|
![]() So I got the IC to replace, it was indeed the 5V regulator IC.
All caps measured OK, I checked the values of each pin before and after replacement and values were all OK. So Ive connected power to it, but still no joy, unit does not power up. Now I have 5V on the left coil, but the smaller one on the right, which I think is the 3.3V , has 0V. The IC with ref. 336K2 has 19V at the 2nd pin, but 0V at all other pins. Pin 3 is output as its connected to the coil. Googled "336K2" did not give me much result, how can I find the datasheet for this one also? No shorts found on this IC either, only pin4 which is ground. Any hints? Thanks! |
![]() |
![]() |
![]() |
#6 |
Great Sage 齊天大聖
Join Date: Dec 2009
City & State: Europe
My Country: some shithole run by Israeli agents
I'm a: Professional Tech
Posts: 26,844
|
![]() |
![]() |
![]() |
![]() |
#7 |
Badcaps Veteran
Join Date: Jun 2012
City & State: ☻
My Country: Canada
I'm a: Professional Tech
Posts: 8,161
|
![]() On that ic, Pin2 is the Vin, but you will not have any output if the EN (enable) pin is 0 volts, I suspect the regulator is not being told to turn on. If the 5v regulator went bad, it may have damaged other components it supplies, If it supplies standby for the main microprocessor, it may have been damaged? Try and trace that 5v line and see what it supplies, it may be something like a open 0Ω resistor that feeds a critical ic.
Last edited by R_J; 10-08-2021 at 10:06 AM.. |
![]() |
![]() |
![]() |
Thread Tools | |
Display Modes | |
|
|