An Aluminum Polymer Capacitor is quite rugged: designed to be operated continuously at rated voltage. These capacitors are characterized by low ESR (equivalent series resistance), high ripple current, and stable performance over temperature. Aluminum Polymer Capacitors are polarized (like aluminum electrolytic capacitors) and are not intended to be used with reversed voltage. They can, however, typically withstand reverse voltage pulses or transients up to 20% of the rated voltage. They are also capable of operating with up to 10% of the rated voltage when reverse voltage is applied continuously.
Aluminum Polymer Capacitors have reliability advantages over both aluminum and solid tantalum electrolytic capacitors. Unlike aluminum electrolytic capacitors, there is no liquid electrolyte that can evaporate and cause a failure. Unlike solid tantalum (which can fail, short and burn), Aluminum Polymer Capacitors gradually become open circuits after 25 to 50 years operation. Applications include DC-DC converters, voltage regulators, decoupling, etc. Attributes which can be important when choosing the appropriate Aluminum Polymer Capacitor for your application include Temperature Range (°C), Rated Voltage (VDC), ESR (equivalent series resistance; in Ω), Ripple Current (Amps), Load Life (hours), Package Type, and, of course, Capacitance Value (µF) and Capacitance Tolerance (%).
