Hello,
here are more X-ray images of xx1117 linear voltage regulators from different manufacturers.
I started wondering after a TS1117 died in one of my designs for no obvious reason.
So i investigated and came up with a simple way to torture the regulator.
I wanted a realistic test, so the test circuit i made is not exceeding the limits of the regulator itself.
What i did was using insufficient cooling to make the thermal shutdown kick in.
The circuit supplies the IC with 12V, while the load is 200mA at 3.3V output.
After 3 days the TS1117 died, no burns, no pop, just gone.
After 11 days the LT1117 was still alive.
I have been told that you can see the suffering of the IC by a change of the output voltage with no load at room
temperature so i measured that before and after the tests. Apparently when the reference inside is drifting that can be a
sign of stress.
The TS1117 had 3.328V before and 0 after the tests.
The LT1117 had 3.309V before and 3.310V after the tests.
So i wondered how they look inside and guessed that the die in the LT is bigger than in the TS.
Which was confirmed.
The prices I quoted in the picture are all Farnell/element14 prices for 1 piece each.
It's interesting to see how different they are inside.
1) Looking at die size vs. price I would say the TLV1117 is the winner.
2) The LT1117 is the most expensive one but if price is not the issue and you need something really reliable thats what you
should go for. Notice the thick bond wires.
3) The TS1117 is only cheap in volumes and die size/experience wise the looser of the lot. Look at the thin bond wires,
LOL.
4) The NX1117 is also very cheap in volumes, the die is small, so maybe if you dont need much power this is a cost
effective part for a design.
5) The ON Semi Conducter one looks good too, mid range i would say. Slighly more elaborate then the TLV.
6) THE ST LD1117 looks nice too, seems to have a nice stable case.
I hope you enjoyed the x-ray images and that they help you to choose the right manufacturer for your design.
Below is the high-res version for download (I hope).
Cheers
Chipguy