Ways to test a switching IC like TOP266EG with a multimeter?

[cemtu]

TL;DR

What are the ways to test a switching IC like TOP266EG with a multimeter?

What are the ways to test a switching IC TOP266EG with a multimeter?(measuring it outside of card circuit)(after uninstalling the component from the card)

Link to the datasheet: TOP266EG Datasheet(PDF) - Power Integrations, Inc. (alldatasheet.com)

Here is the DATASHEET picture:

TOP266EG IC HAS THE SAME APPEARENCE

 

[berkeman]

What do you mean by "test"? You have a PC board with this circuitry on it and it's not working and you want to troubleshoot it? Or you have the loose IC and want to know some way to tell if it's okay or not?

 

[cemtu]

What do you mean by "test"? You have a PC board with this circuitry on it and it's not working and you want to troubleshoot it? Or you have the loose IC and want to know some way to tell if it's okay or not?

loose IC, yes

"Or you have the loose IC and want to know some way to tell if it's okay or not?"
this, yes.

 

[berkeman]

loose IC, yes

Can you say more about *why* you want to do this? Just to practice probing some loose IC? Or is there a reason you are wanting to check out this particular IC?

 

[Rive]

What are the ways to test a switching IC TOP266EG with a multimeter?...after uninstalling the component from the card...

There is no way to 'test' it.
The problem is, that even when it's still installed the only real way to 'test' it is while it's on line voltage.
And that's not recommended if you are not somebody qualified.

ps.: if it's some repair attempt, then the most I would do is to check:
- the fuse: there will be a fuse somewhere
- that resistor connecting to 'V' pin.

Only measure when it's disconnected and already no remnant voltage present on the caps.

 

[DaveE]

Short answer, no, not really. ICs with multiple functions require more sophisticated setups. That's why the data sheet will have test circuits in it. There's a reason the datasheet is 40 pages. BTW, thanks for that link, you get an A+ from me for question format!

A common way for these things to die is that the output MOSFET is destroyed. You may be able to test that with an ohmmeter if you can set up the IC* to either try to turn it on, and test for a low impedance, AND to try to turn it off and check for a high impedance. You won't be able to say it's OK, but if you are confident you are setting it up correctly for these tests, you could decide that it's broken.

For ICs like this, my experience is that the problems are usually some misunderstanding about the IC and/or the circuit that it is actually connected to. That, or it's obviously broken. If it has never been used, it should be safe to assume it's OK; these aren't that fragile.

* this would be in a special purpose low voltage test circuit that you make.