Component identification - big ask - Page 1
Forum section: electronics / beginners

author: mw52563
author_rank: Contributor
timestamp: April 28, 2020, 01:11:59 pm
content: Hi,Im still trying to repair a treadmill PCB.. Im down to the last component that I think might be causing problems. Problem is its really hard to see and Ive broken it when removing it. So Im hoping someone with more knowledge might be able to work out what it is from zoomed in pictures that arent easy to see. These are the zoomed in photos and the location. Is it possible a mosfet?Thanks for any helpRegardsMikeLocation

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: April 28, 2020, 01:42:14 pm
content: Could it be a voltage regulator?Something like this?But a different package.http://www.ti.com/lit/ds/symlink/tps737-q1.pdf?ts=1588081257685

author: Paul Moir
author_rank: Frequent Contributor
timestamp: April 28, 2020, 01:53:41 pm
content: It's a pain in the neck for all of us trying to help when you break up your posts.https://www.eevblog.com/forum/beginners/circuit-board-leg-missing-of-timer/https://www.eevblog.com/forum/beginners/igbt-question/It just wastes our time barking up the same tree over and over again. Please don't do this. Please do post a photo of the back of the board as previously requested since this will help us confirm pinouts.

author: Manul
author_rank: Super Contributor
timestamp: April 28, 2020, 06:02:08 pm
content: On another of your posts I asked is it really nothing written on this IC and you said "Ive cleaned it all off, i cant see anything on it". And now it is written, but damaged. Well... I also asked about pins connected together, trying to identify is it a common LDO pinout with no answer.Please post a good quality picture of that section of the board from both sides. We can make a guess then.

author: Andy Watson
author_rank: Super Contributor
timestamp: April 28, 2020, 07:29:46 pm
content: The transistors are labelled as "Qn" but the chip is labelled "U6" - so probably not a mosfet. I would guess that it is a half-bridge driver. with D6 and C19 providing the boost/bias supply.Similarto an IR2183. Google "soic 8 half brdige driver", there are plenty to choose from.Note I said "similar to" - more information is required. You might get some more hints by googling for images of that PCB and also whatever the controlling chip is (U1 ?) I don't want to piss on your chips but if there was sufficient fault power to remove the leg of the chip I would susspect that the rest of the board is toast too.

author: mw52563
author_rank: Contributor
timestamp: April 29, 2020, 06:38:58 am
content: HiI said I couldn't see anything because I couldn't... I had to use a microscope feature on the phone then adjust the image in Photoshop and i still can't really make out what it says. There's no continuity between any of pins, I tested this before removing it.I don't actually think the leg blew off, I think whoever made the board used glue around the big capacitor and when I pulled it off it took the leg with it.Thanks for all the helpRegardsMike

author: mw52563
author_rank: Contributor
timestamp: April 29, 2020, 07:02:12 am
content: Managed to use a better camera.. I googled D29 plus soic 8 half brdige driver and the bottoms component came up... It's got a little indented hole on top as well.

author: Mechatrommer
author_rank: Super Contributor
timestamp: April 29, 2020, 11:02:27 am
content: you can guesstimate what the IC do from looking at the traces in and out on the pcb to the IC and possibly find a compatible replacement.

author: mw52563
author_rank: Contributor
timestamp: April 29, 2020, 02:38:14 pm
content: I'm pretty sure it's this, but thanks for all the helpRegardsMikehttps://www.ebay.co.uk/itm/202250123651