James

The 12 V automotive rail is the one power bus nearly every electronic module on a car shares, and it is also the least “regulated” rail an engineer will ever design against. Over a single day of driving, the same two terminals that start the engine with a few hundred amps also carry the alternator’s … Read more

The qualification of a solar module is a gauntlet of environmental tests, and the bypass diode is tested inside them — sometimes explicitly, sometimes as collateral damage. A module that passes the lab can still fail in the field, and the difference is often visible in which test the diode was stressed by and how … Read more

PV bypass diode failures appear as string underperformance or a damaged junction box, and the evidence chain runs from the shading pattern to the junction-box temperature. This guide covers the failure mechanisms, the hot-spot damage patterns, the thermal evidence, and the module-versus-device attribution. Last updated: October 16, 2026 Why Bypass Diodes Fail in the Field … Read more

Every automotive engineer has heard of load dump, and most have heard only one number: 87 V. Fewer can explain why the rail spikes that high, why the spike has an energy and not just a voltage, and what actually survives it. Load dump is not a single clean pulse; it is the consequence of … Read more

An electric vehicle is not one power stage; it is a map of them. A traction inverter, a DC-DC converter, an on-board charger, a set of auxiliary loads — each stage runs at a different voltage, frequency, and duty, and each has a device chemistry that fits it best. The recurring question “MOSFET or IGBT?” … Read more

Two diodes protect a solar array, and they share names that sound interchangeable. The bypass diode protects the module from shading; the blocking diode protects the battery and the string from reverse current. The placement gives them away: the bypass diode sits in parallel with a substring inside the module, and the blocking diode sits … Read more

A solar module contains a protection diode you never see and rarely think about — until a shaded cell or a cracked cell makes the whole string underperform. The bypass diode sits inside the junction box, wired in parallel with a group of cells, and its job is to carry the string current around a … Read more

An H-bridge drive for a motor has two hidden electrical paths: the switching path that everyone sizes, and the freewheeling path that nobody does. When the H-bridge releases a motor, the back-EMF drives current through the Zener or the protection diodes that absorb the stored energy — and that reverse path, repeated thousands of times, … Read more

The Zener’s reputation as a “voltage reference” suggests it holds its voltage like a calibration standard, and the honest answer is that it does not — a Zener holds its voltage within a tolerance, it drifts with temperature, and the sign of that drift changes around 4 V. For many circuits the Zener reference is … Read more