Hello can anyone help us to identify this burnt out IC?
It is a Lowrance Eagle 9 sonar. So there is no schematics available.
Measurements are between the outer pins 1.5mm so I would say it’s a sot-23-8.
Pin layout we found so far after removing the IC. Pin 4 ground, pin 3 VIN (12v) and pin 2 3v in. From bottom left.
Hello rataryrealm,
Welcome to the DigiKey TechForum.
I’m sorry to say, but without the specifications, or top markings, there would be no way to determine what type of IC that is, or to find a replacement.
Well, it’s smaller than a SOT23, based on it’s relative size vs. the “WHR” part, which is certainly a SOT23.
The circuit is unusual, as it looks like it is using resistors in series rather than single ones connected to various pins around the chip. That would likely be either because they could not find single resistors of the right value so they had to string two together, or, more likely because they wanted to split the power load between two resistors.
That implies that a fair amount of current might be expected to pass through there, relative to it’s size. Possibly some sort of TVS array? Pure guess there.
Let me offer my hypothesis.
I think it’s a DC-DC Synchronous Step-Down Converter.
As an example, I’ll use the MP1495S.
Until we know all the data for Vin, Vout, FB, Switching Frequency, and Current Limit, it’s impossible to suggest a suitable IC.
It is necessary to thoroughly clean the microcircuit and identify at least some letters or signs.
IAGPR, AGPx - MP1495SGJ-Z.pdf (888,0 КБ)
Guessing this is a power path switch, e.g. e-fuse, probably in SC70-8 package, which has transposed to a traditional fuse. Could not find anything with the correct pin-out.
Cheers, heke
