The circuits in post #41 are XOR not XNOR.
Their main disadvantage is they they waste more than more than normal lamp current when one one input is on, and more than twice the lamp current when both inputs are on.
Hm. You're using PNPs (2N3906) for ALL 3 transistors. Which I recognised, and tried, and decided must be a mistake as that was even less 'working' than with NPNs:
Of course, if you'd shared your LTSpice implementation, I wouldn't have had to try recreate it myself.
That's why I used Falstad to demo for sxy; no dependancies. (Nor steep learning curve; nor stupid UI;...)
(+ visual indication of current flows and rates; mouse over scoping;...)
See here for a working Falstad implementation of Crutschow's XOR/XNOR circuits. Note that the XNOR version is the XOR + a NOT gate to invert the output.
Answer (1 of 34): TL;DR — the diode is a passive device. It is a nonlinear “positive” resistor, whose I-V characteristics lie in the 1st and 3rd quadrant of the I_D-V_D plane (see picture below), and by definition positive resistors are passive elements (they always dissipate power/energy — note ...
(Bild: Public Domain) One key factor that differentiates types of electronic components from each other is whether they are passive or active. However, many people are unsure of exactly what that difference entails. This article is here to help.
(Bild: Public Domain) One key factor that differentiates types of electronic components from each other is whether they are passive or active. However, many people are unsure of exactly what that difference entails. This article is here to help.
As you can see there is no biblical definition of active versus passive.
But that guys def leaves one to wonder why he considered diodes as active
In a nutshell, active components can, generally speaking, inject power into a circuit and are capable of electrically controlling and amplifying the flow of electrical current, whereas passive components cannot.
Of course we can spend a year or two debating what applies to what in the above def.....UGH.
Here they are considered passive, but then broadly classify tube's as active, would that
also be true of tubes with no elements, no connections. Silly.