Humax sat receiver HDR - 1100S Help identify part.

[Dumar84]

Hello, Im trying myself in electronics repair, with zero knowledge :-)
I have Humax sat receiver HDR - 1100S it won't power on. I found short on part ML5ED been advised that it was dc dc converter SY8113 (ordered on AliExpress and waiting for delivery)
And when been measuring voltages on the board I shorted contacts in another part �� and hoping someone will help me to identify that part. PT5RA its 2mm x 2mm size
See attached pictures
Thanks in advance.

[Dumar84]

Re: Humax sat receiver HDR - 1100S Help identify part.

Bottom side picture.
Anyone know what this is, is this some sort of MOSFET?
Thanks

[R_J]

Re: Humax sat receiver HDR - 1100S Help identify part.

I can't find much, it does seem to be a case type U-DFN2020-6 (type J)
any idea how it is used in the circuit?

[Dumar84]

Re: Humax sat receiver HDR - 1100S Help identify part.

I can't find much, it does seem to be a case type U-DFN2020-6 (type J)
any idea how it is used in the circuit?

Thanks very much for your reply.
This receiver has two of them on the circuit board, same number (PT5RA) on the board marked as U4304 and U4305
I removed U4305 because I shorted pin 1 with pin 2 and it burned hole in it.
On U4305 (removed) voltage is:
Pin1 0.092v
Pin2 12v
Pin3 3.37v
Pin4 about 0.500v when starting measuring voltage drops to 0v
Pin5 Groung
Pin6. 0.035v
On the U4304 (second one on the board)
Pin1 3.51v
Pin2 12v
Pin3 12V
Pin4 6.52v
Pin5 Groung
Pin6 0.608v

I also have working humax FVP-4000T Freeview receiver
Its similar board inside, but not the same.
It has same looking chip but instead of PT5RA its PT5OA and only one chip(satellite receiver has 2)
Voltage on FVP4000T is: (switched on and on standby same voltage)
Pin1 1.53v
Pin2 12v
Pin3 3v
Pin4 4.49v
Pin5 Groung
Pin6 0.606v
I will also attach pictures.
Thanks in advance

[R_J]

Re: Humax sat receiver HDR - 1100S Help identify part.

It looks like the part number is PT5xx where xx is a date code. They seem to be a buck regulator ic, so not just a mosfet.

[Dumar84]

Re: Humax sat receiver HDR - 1100S Help identify part.

It looks like the part number is PT5xx where xx is a date code. They seem to be a buck regulator ic, so not just a mosfet.

Thanks for your reply R J
I found AP133 in DFN2020-6 package but its for 2v to 6v
I need for 12v.
I emailed Diodes to see if they have any alternative for me.

Thanks