Not vintage, but LED light teardowns seem to be popular. This one is a submersible LED light for use in your bath, hot tub, vase. It is available on eBay for ridiculously low prices eg. $3.39 with free shipping
I had mine for over a year, and it worked quite well (though it was a bit of a battery hog.) However after a time the remote has stopped working.
So lets tear it down and take a look, here is the PCBThere is not much to it just the 10 LEDs, 3 transistors, a handful of resistors and capacitor, the IR receiver diode and an 8 pin driver chip on a metal board that acts as a heatsink.
So of course lets decap this. When I did I was quite surprised I expected to see a fairly simple analog die like the Bright Power Semiconductor LED driver I previously looked at. This is nothing like that!(As always click on image for high resolution version)
With as many as 6 levels of Cu metal, and likely made on a 90nm CMOS process it is very dense. Even the large driver transistors are not really visible. Its still a very small die just 1.5 mm x 0.5 mm (0.75 mm2), putting that in a die per wafer calculator, I get over 70,000 die on a 300mm wafer!
There is no company logo and the only die markings (Tritan Mar 2014 TT3015.) I suspect this could be a (Chinese) fabricated clone of someone else’s LED driver chip.
A simple construction is used for the receiver. A front plastic layer that is glued to the front of the board with 32 button locations (24 are used.) On the back just the battery connection, IR diode and a single chip encased with a glob top.
So I decapped the glob top chip and unfortunately had a DECAP FAILURE 🙂 It happens, though might be unusual to lose 3 corners and crack the die right down the middle. The die is the smallest one I have come across just 0.8 mm x 0.7 mm (0.56 mm2).