I was trying to repair the main board of a monitor (Samsung S27B750V), and after a few hours I did something I shouldn’t have, and blew this component. I have tried to search for this but I am unable to find anything about it. Need to have it replaced. It reads “SOZ B21” I believe.

Perhaps there is an alternative to it? I have a lot of old PCB's laying around, but have never seen this kind on any of them.

EDIT: After uploading both photos I see they have different text in the middle.

Dimensions are 4.3 x 2.4 mm

SOZ B21 component (Samsung S27B750V) enter image description here enter image description here

  • 3
    \$\begingroup\$ Welcome to EE.SE! What capsule size is this? Your image appears stretched. Also, please zoom out a bit so we can follow the traces. \$\endgroup\$
    – winny
    Nov 7, 2019 at 12:24
  • 3
    \$\begingroup\$ Can you provide an image showing a bit more around the component - making it easier to guess its functionality by what it is connected to :) \$\endgroup\$ Nov 7, 2019 at 12:25
  • \$\begingroup\$ @winny To me it looks like a SOT89-5 \$\endgroup\$ Nov 7, 2019 at 12:26
  • \$\begingroup\$ @RichardtheSpacecat - The parts have 6 leads if you look closely at the pictures. \$\endgroup\$ Nov 7, 2019 at 12:39
  • 2
    \$\begingroup\$ Nicely asked question with good photos... +1. \$\endgroup\$
    – rdtsc
    Nov 7, 2019 at 14:27

1 Answer 1


My best guess it's an ABLIC S-1172B33-U5T1x low dropout regulator (3.3V).

S1172 series LDO

SOZ denotes the 3.3 V version and B21 is the lot number.

enter image description here

  • 1
    \$\begingroup\$ Very nicely done. \$\endgroup\$ Nov 7, 2019 at 13:19
  • \$\begingroup\$ Wow, thank you so much! That definetly answers why it went. I gave it 14V.. \$\endgroup\$
    – Andreas
    Nov 7, 2019 at 13:22
  • \$\begingroup\$ @Andreas You are most welcome! Or should I say du är väkommen? \$\endgroup\$
    – winny
    Nov 7, 2019 at 13:23
  • \$\begingroup\$ Now hopefully no 3.3v devices are damaged... \$\endgroup\$
    – rdtsc
    Nov 7, 2019 at 14:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.