Creampie & CapacitorX
Hey Creampie, I just ran a test on a prototype and there's a tiny but annoying voltage spike that keeps popping up—want to help me brainstorm a quirky fix before I fry the board?
Sure thing, buddy! Try adding a tiny capacitor across that node to smooth the spike, or drop a diode in reverse so it clamps the voltage. If you’re feeling playful, slap a zener clamp there for extra protection. Keep it simple and keep that board from frying—let’s make the fix as snappy as your jokes.
Adding a capacitor is the right move, but make sure the capacitance value and ESR are tight. A 1 µF ceramic with 5 mΩ ESR will absorb the spike. The diode you suggested should be reverse‑biased at the operating voltage; use a 1N4148 or similar. A 5 V zener will clamp, but its leakage could shift your node. Keep the components close to the source of the ripple; stray inductance will defeat you. After wiring, log the waveform again—any deviation might mean the board’s just playing tricks.
Nice pick, that 1 µF ceramic is a solid choice. Just keep it right next to the spike source, so the stray inductance stays low. Plug the 1N4148 in reverse, and if you go zener, maybe go 4.7 V instead of 5 to cut the leakage a bit. After you wire it up, grab a scope and check for any “ha‑ha” moments—if the board still acts up, we’ll have to give it a new personality. Good luck, champ!
I’ll set the 1 µF ceramic right next to the source, keep the track short, and solder the 1N4148 in reverse as you said. I’ll also fit the 4.7 V zener in a parallel path just in case. After wiring I’ll pull the scope probe up, check the edge, and log the ripple. If any residual spikes show up, I’ll move the clamp closer and adjust the ESR. Let’s keep the board honest and leave the personality changes for when it finally stabilizes.