Bad THS7314s in circulation

Hi guys,

Long time lurker, first time poster.
I've been modding primarily Japanese import consoles with great success, but I recently ran into a problem.
I got a shipment of 16 THS7314 for N64 RGB mods, and it seems that all of them are dead..
I wired them up on a breadboard, fed them +5V, GND and the R-component from an N64. Probing it, I can see the video-signal on the input pin just fine, but the output pin is mostly noise, with a very low Peak-to-peak (10s of mV). I figured that chip was defective, but after testing a few more, it seems that all of them are dead..

Have you guys had any problems with bad THS7314s? Or, am I missing something? Are they extra sensitive to heat during the SMD soldering process?

 

I'm powering them using a proper laboratory power supply, so I'm definitely within its voltage range. But, for shits and giggles, I'll give one a go at 3.3V

 

I've used 5V to power them in my SNES Mini, N64 and Duo R. No issues whatsoever.

 

Did you get them from a legit source like mouser or digikey? Or from ebay/aliexpress from China? I have had a few not work out of a batch from China(ebay) last year so I stopped ordering those and started getting them from Mouser. They arent that much more expensive to get from there.

 

Yep, it was fleabay+china I got them from (was in a hurry, and they shipped faster for cheaper).

Got a shipment from a second source today, and they're all working perfectly.

So, beware people. There are bad ones in circulation...

I couldn't see any difference in markings when comparing with the good chips, so I don't think they're counterfeit. Might be that someone helped themselves to the "bad" pile in the factory?

 

Thank you for the warning. I might need some soon, so this is great to know

 

I bought amp chip from retrorbg on wednesday it showed up in mail yesterday and I installed it last night. Everything is working perfectly.

 

Possibly they were cooked by customs? Xray?

 

I bought a strip of these from aliexpress and now I have concerns. I have noticed that they all seem to have different codes on them, but on another strip I have they are all the same code. I haven't tested them yet but I am now fearful, shouldn't they all have the same code when they are in a strip from the same reel?

 

Normally all the parts on the same reel will have the same date and/or trace codes, or at the most two different ones if it was on the changeover between two batches.

If you have a bunch of parts on the same tape all with different codes they are probably recycled (I.E. used parts removed from boards) - so they are real parts, just not new ones. This also strongly implies that the original vendor was selling them as refurbished parts, since the people that are trying to pass them off as "new and original" will typically remark them all with the same codes.

 

beware of used parts. They nay not have been tested at all.

 

I have installed one of the suspect chips in a console ( this is the only way I could test it as I don't have any logic probes etc.) and it works. Perhaps the chips in the strip were rejected for some other reason but are fully working?