Low-impedance aluminum electrolytic capacitors are polarized passive components designed with specialized electrolytes to minimize Equivalent Series Resistance (ESR) and impedance, particularly at higher frequencies. They offer high capacitance-to-volume ratios, making them essential for input/output filtering, smoothing, and power supply decoupling in electronics.
When selecting, prioritize the required capacitance, voltage rating, maximum temperature, and, most importantly, low impedance/ESR values at the target operating frequency.