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Help identifying the SMD component

Hi, please help identifying the burnt SMD component ( I suggest it is a MOSFET ). It is from 2.4 GHz AV transmitter (picture attached). There are partially remaining simbols on burnt chip (see freehand writing on right down corner ). I try to partialy track the PCB . I apply close view of the PCB also (both sides).
 

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It is a switch mode regulator of some sort, stepping the input voltage down to a controlled level for the 78M05 so it doesn't dissipate too much power.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Actually it seems to provide another rail, so it's not just to reduce distortion in the 78L05, even though it does do that too.
 
Thanks for your suggestions. First I also supposed the IC to be 9V voltage regulator but could it be a MOSFET , connected as reverse voltage protection, and that SMD component to be 2 MOSFETs in one chip.?
The IC is too tiny to be voltage regulator, which assure 0.5 A as 78M05 will. The input voltage is announced to be 9-12V DC.
If we assume the input voltage is 9V , would it works as regulator?

When I post this topic ,as a last chance , I hoped that somebody has the same transmitter and will be kind to check the chip.
I spent about a week in searching the net for close view of the transmitter PCB and suitable IC , but with no result. I even can't find a chip manufacturer with such a logo.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Why do you think it's too small? Switching regulators do not dissipate a lot of heat.

If your circuit diagram is correct ( and it looks like what I'd expect) then it is a switching regulator.
 
Thank you very much. You are right.
I found a XLSEMI switching regulator XL 1509 , with the same pin configuration and the same application circuit usage.
It must be this chip or similar one. Thanks again.
 

Attachments

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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Well done! The one you need is the one with the adjustable output voltage.
 
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