Power tip 50 is on aluminum electrolytic capacitors.
Aluminum electrolytic capacitors remain a popular choice in power supplies due to their low cost. However, they have limited life and are sensitive to both hot and cold temperature extremes.
Aluminum electrolytic capacitors are constructed with foils placed on opposite sides of paper saturated with an electrolyte. This electrolyte evaporates over the capacitor’s lifetime, altering its electrical properties. If the capacitor fails, it can be spectacular as pressure builds up in the capacitor, forcing it to vent a combustible and corrosive gas.
Robert Kollman is Senior Applications Manager and Distinguished Member of Technical Staff at Texas Instruments with more than 30 years of experience in the power electronics business. His latest contribution in the Power Tips series can be read here.