June 29, 2017
ST 2STD1665 - power NPN BJT : weekend die-shot
ST 2STD1665 have quite outstanding hFE of 320 (for a non-darlington 65V power BJT). That makes it very useful for switching applications where you wish to drive it with low voltage (e.g. pin of microcontroller with 1.8V VCC) where N-MOSFET would require external circuitry.You can see extensive net to stitch thin, high-resistance base with metal. Emitter resistance could have been slightly lower with different pad placement (closer to center and on the diagonal) but apparently it's not a major performance-limiting factor.
And... it's just beautiful!
Die size 1740x1727 µm.