Help needed to identify broken component on PCB

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SapeS
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Help needed to identify broken component on PCB

Dear forum members, I recently discovered your website on LED flash lights and related items. I have a NaturalShine LED dive light which I ruined myself. The original battery pack consists of two 18650 cells in parallel. I tried to use two cells recovered from a laptop battery pack but placed them serial. The result is not difficult to guess. I'm trying to repair it but haven't been successful yet. Therefore you are my last resort.  See URL's for the pictures below. The manufacturer seems to be a Chinese company named Edi-t.The driver is a 3-mode low, high and SOS type. The modes are selected by a rotating ring containing a magnet that activates three hall effect sensors H1, H2 and H3. The 8-pin IC U2 has no identification. Else, I see two resistors R1 and R2 (both 30 ohm) and two capacitors C1 and C2. The defective component U1 has already been removed. The PCB diameter is 20 mm. The led is marked Cree XML. The broken part has a SOT-89 housing and has a marking BH. Underneath this marking you see the crater caused by the incident.My search on the Internet led me to an NXP BCX56 NPN transistor but I have difficulties to believe the collector is connected to the LED positive. Do you recognize the type and layout of my driver? Do you have a suggestion about the identities of U1 and U2, or at least the type of components?

The pictures are on a public Dropbox site:

https://www.dropbox.com/s/juozdrl73skvn2t/IMG_6405.JPG?dl=0

https://www.dropbox.com/s/6fem9uhx6r9thw2/IMG_7890.JPG?dl=0

 

Yokiamy
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It looks like an 7135 to me

WTB: Jetbeam TCR-1 or Sunwayman V10R Ti

SapeS
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Thanks for the quick reaction. I assume you are referring to AMC7135? I don’t believe this is the one I’m looking for. See datasheet here: https://www.dropbox.com/s/iaf6sharqs5ppbu/AMC7135%20current%20regulator%... .
Leg #2 is ground, but on the PCB it will connected to the LED’s anode (L+) so this is a contradiction. The current is 350 mA while the Cree XML spec is up to 3000 mA.
I found another PCB from Fasttech.com with a similar layout. See https://www.dropbox.com/s/9h4plspbzem1swx/HS602C.png?dl=0 . This has an IC marked N012W and has a similar orientation on the PCB, that is leg #2 connected to anode. There is a Danish website that published test results for it. See https://lygte-info.dk/review/DriverTest%2017mm%205-Mode%20LED%20(HS602C)%20UK.html . I’m not able to find a datasheet for this N012W.
Apparently the 8-pin IC produces a (PWM?) signal for high, low and SOS which is input on leg #3. Leg 1 is connected to battery +. So U1 controls the current to the anode based on the input signal. At least, that is my impression based on limited knowledge of electronics.
Somebody else has a suggestion?

kennybobby
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i think it would be a PNP transistor or p-FET if pin 1 is getting the base or gate drive signal from the 8-pin IC. pin 1 is left of the center (pin2 + tab) and pin 3 is to the right of center and connected to B+. This is fairly standard pin numbering for these devices, what you have described seems like an opposite numbering sequence..?

Now i used to think that i was cool,
drivin' around on fossil fuel,
until i saw what i was doin',
was drivin' down the road to ruin. --JT

SapeS
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Joined: 02/14/2021 - 10:45
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@kennybobby,
Indeed I was wrong on the pin assignment. I’m now pretty much convinced it must be a P-channel logical MOSFET. Left (#1) is gate, middle (#2) is drain and right (#3) is source. See https://www.dropbox.com/s/edgezangkmeq84c/IMG_7890-mosfet.jpg?dl=0 . Now I must find a suitable spec.