ANIMON CONNEX repair - unknown voltage regulator

[fester]

Hi friends,
i have this device,it is actually fullHD video transmitting system with 1ms latency,specialy made for big drones. I have problem with receiver,first i replaced one 0ohm resistor-this resistor was blown(the same problem was on another unit before when someone plugged reversed polarity in),now if i plug power in and switch on,nothing happens,no LED light,nothing.it takes arround 250mA from power source,what is too low,correctly it should take arround 1A and more. I meassured some voltages,there are markings on the board and i fount that on 5V line is arround 4,4V only. I found also regulator which generate this voltage but cannot find type or datasheet for this chip and meassure more.
Know this chip someone? Thanks in advance.

[stj]

Re: ANIMON CONNEX repair - unknown voltage regulator

give us a hint, which resistor did you burn??

btw, FS1 is a fuse.

[fester]

Re: ANIMON CONNEX repair - unknown voltage regulator

FS37 was burnt,. Yes i know FS1,i meassured it already,is ok..also every other 0ohm resistor on the board

[stj]

Re: ANIMON CONNEX repair - unknown voltage regulator

maybe Q1 or U1 is bad.
need a better photo to see the part numbers etc.

[piernov]

Re: ANIMON CONNEX repair - unknown voltage regulator

The chip marked "0N=" is most likely a Richtek RT6150A.

[fester]

Re: ANIMON CONNEX repair - unknown voltage regulator

hi guys,piernov it looks like this chip also for me,pcb layout is almost the same as in datasheet,thank you for this, first i meassured voltage on the coil,there is 4,5V but on the output capacitor is the right voltage so this regulator is ok. But i have always 4,5V on the J4 and other point on the pcb marked as Vcc_5V..
stj - i made some better photos but not perfect,dont know if can make it better,my phone camera is not the best one and i dont have camera on my scope..

[fester]

Re: ANIMON CONNEX repair - unknown voltage regulator

As i found,U1 is some kind on charge pump for double mosfet Q1,i have arround 22V form U1 on both gates and voltage from power source on both sources and drains - this part look also good for me.
Without power are both mosfets not shorted.

[fester]

Re: ANIMON CONNEX repair - unknown voltage regulator

I hope i found the right regulator which create this (not) 5V voltage under the shielding cover,also found zener diode with forward voltage 0,06V,reverse is open,i dont have meter for zeners but i will try to replace this diode.on the picture is this diode soldered out for meassuring but this look really promising to me..