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Can anyone identify the burned chip on this circuit board? It is a Chinese motorcycle dashboard, but the design is probably from Kawasaki Rouser. The chip might not be burned, but one pin is broken so I want to try replacing it with a new one, but have no idea what it is...

enter image description here enter image description here Any help is appreciated!

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  • Here is the view from a microscope: i.imgur.com/WRgagHD.png – ajayver Feb 27 '16 at 12:07
  • On semiconductors formerly part of motorola – Andy aka Feb 27 '16 at 12:15
  • The PCB trace to the left of the electrolytic cap(?) looks a bit burned - what happened to it? It may be that other components have suffered, even if not visibly. – Roger Rowland Feb 27 '16 at 13:03
  • Just based on the layout it's defiantly a power regulator, the large ground on the tab, the big filter cap on the input. The "on" in a circle is the On Semi logo. Obviously something shorted out, as it looks that the input trace also fried. The burnt trace and regulator are a Symptom, not the root cause. – cde Feb 28 '16 at 6:11
  • Also its definitely burned out. Either the input was significantly higher than expected, like it was connected to mains voltage instead of 12~14 car voltage, or the current draw was excessive like a dead short. – cde Feb 28 '16 at 6:15
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It is a 5V LDO linear regulator, seemingly NCV4275A. Here is what it should look like if it weren't half burned:

Picture of NCV4275A5 regulators

The burned trace and bulged 50V 220µF capacitor are on the input side; the two 100µF 16V capacitors appear to be on the output. The former will definitely have to be fixed along with the replacement of this regulator, but, as Olin points out, there may be more extensive damage that isn't visually apparent.

  • Note to the anonymous user: please post your own answer; don't edit your unsubstantiated speculations into mine. Also, you may want to buy a better soldering iron and a hot air rework station. – Oleksandr R. Feb 27 '16 at 18:56
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This unit is toast. Replacing the one obviously burnt chip will not fix the problem, and may just cause the new chip to get blown up too. Something bad happened to this board, which clearly caused more than one chip to be damaged. Get a new one and this time don't short the output, hook it up the wrong way to the battery, or whatever caused the problem.

Note the vaporized trace to the left of the top electrolytic capacitor. A lot of current went thru there. A little bit of the copper is still left near the capacitor. I also don't like the bulging top of the cap, and the fact that this is apparently a no-name type without a vent. When it goes, it's going to take a lot more stuff with it.

Put another way, the burnt chip is just one symptom of a much larger problem.

  • 1
    +1 That is clearly a switching regulator chip, and it didn't die because it just felt like it. Unless the external problem is fixed, any replacement IC will also die. Note the damaged parts to the right of the left-hand display. – WhatRoughBeast Feb 27 '16 at 15:34
  • The diode next to the pin labelled VIN in the first picture (follow the vaporised trace around) also appears totally ****ed. Seems like either too much voltage was applied, or polarity was reversed (or both). Either way it would take a lot of effort to try and rectify it. – Tom Carpenter Feb 27 '16 at 16:04
  • The voltage regulator failed on this motorcycle, causing a lot of current to the dashboard and burned it. Actually the capacitor burned first and affected the chip, so one pin is now disconnected. The voltage regulator has been replaced on this motorcycle, now I hope I can find all the damaged parts and replace them. – ajayver Feb 28 '16 at 14:43

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