Help IDing part: TSSOP8, top mark "MHJ"

[Evan Shultz]

I guess that says it all. I'd like to figure out what part I'm looking at.

Pin 4 is tied to ground and pin 8 is tied to +5V, so it could be a logic IC?? There aren't obvious feedback and/or input resistors so I'm doubting it's a comparator/opamp.

 

[jitter]

Might help to have some more info, like in what kind of circuit is it used?

 

[Evan Shultz]

Well, that's the problem. This TSSOP8 is in a SMPS, but I don't know what's going on since I can't ID this part.

And I've got another one: SOT23-6, marking is "252Y". It's in a SMPS too... maybe a pair of transistors or a voltage regulator??

 

[jitter]

I googled MHJ+TSSOP and most results pointed in the direction of a switching voltage regulator, so I wasn't surprised at your reply. But that's about as specific as I can be.
All the results were almost exclusively on Chinese websites. Your SMPS is it "made in China"?

 

[Evan Shultz]

I don't know if it was made in China or not. It's probably a good guess.

I Googled the same thing and see the "MHJ" in the part number on many Chinese sites. But I didn't see "MHJ" as the top mark. So I'm no closer. Did you see something I didn't?

How can I find a seemingly random IC from the top mark? Between NXP's and Fairchild's websites, and a couple other top mark listing sites, I can often figure out discrete components. But as for ICs... what to do?

Perhaps the part marked "252" is an IC which is why I'm having trouble IDing it??