On Mon, Feb 22, 2021 at 04:41 AM, Michael Dunn wrote:
E-B are also considered low-leakage, given the low breakdown.
Diode connected BJT (where that mean base and collector are connected) are frequently used in current mirrors (in integrated circuits) ... but that's for temperature compensation reasons.
Diode connected BJTs can sometimes be seen in designs, where for some reason (cost?), the designer specs a diode... but, production uses a transistor.
Those uses for a Diode connected BJT seem common enough.
But using the base to emitter junction as a diode... maybe that's not so common?
Anyway, for a 2N3904 (planar epitaxial NPN silicon BJT, ON Semiconductor)... if you keep the reverse bias below 6 volts (ON gives this as the breakdown), I expect the current to be less than a few pA... maybe less than 1 pA. (One can do the calculations.)
I reckon, the current in a base to emitter configuration is going to be at least an order of magnitude less than a base to collector, Diode connected BJT. ... because the current scales with the area of the junctions.
If you don't fly by math, or by simulation either... then doing the measurements would be great... but, that might not be so easy... but, it would be interesting to know.
