I’m learning about electronic components. I believe this is the part which has broken and made this heating pad unsafe to use. Well, unusable, not just unsafe lol.
No, there’s no fuse here. From top to bottom, there is an electrolytic capacitor, zener diode, and a 4MHz resonator.
Ding ding ding
For op, ZD means zener diode.
If you’re looking for a fault and can’t see it, it’s sometimes possible to sniff it out. Components can be burned out, but the damage is barely visible, if at all. It could be a tiny crack in the packaging. It will often smell like burnt plastic for a long time. Locate the rough area and concentrate on these parts.
If anyone is wondering, that glass diode package is called a MELF. I don’t know why.
They suck because they roll off the PCB during the pick and place process due to low surface area contacting with the solder paste.
I’ve had to replace so many of them.
MELF stands for Metal Electrode Leadless Face although anyone who has had the pleasure of working with them will tell you it stands for Most End up Lying on the Floor.
Hahaha!!! You are soooo very right!!!
