We have all had difficulty testing diodes in-circuit. Most DMM’s have a diode Vf function that measures forward drop, but what is the normal voltage drop?

This Design Idea describes a versatile test circuit for zener diodes after yet another misread zener diode had infiltrated the ranks of 1N4148 diodes assembled on a pc board. As a bonus, the circuit ...

When checking and verifying capacitors, inductors, diodes, bipolar transistors, and cables, the gamut of test methods can range from those used to confirm a defective component to identifying the ...

However, the circuit described here performs a simple go/no-go test on these diodes while limiting forward current and reverse voltage to safe levels (see the figure).

The circuit is simple enough: it uses a capacitor, a resistor, and a pair of diodes (one of them a zener diode). He uses this basic circuit to drive simple regulators with input and output filter ...