KEMET A798 Plus Performance Aluminum Organic Capacitor AO-CAP®

Harsh application conditions in Telecom lead to a new AO-CAP® A798 series lifespan qualification capability: 125ºC/Ur/3000h

Today's challenges that designers need to solve are high demands in power management and miniaturization requirements in combination with high-temperature profiles over the lifespan. KEMET introduces a solution by expanding the AO-CAP ® Aluminum Polymer SMD capacitor with 125ºC / 3000h capability combined with 85ºC, 85% relative humidity at rated voltage up to 1000h in the A798 Series. The product offering was enhanced with the new material setting and manufacturing flow, allowing a specification of endurance life at rated voltage and storage unbiased at 125ºC up to 3000h.

KEMET A798 Plus Performance Aluminum Organic Capacitor AO-CAP® is a solid-state aluminum capacitor. The cathode is a solid conductive organic polymer, which results in very low ESR and improved capacitance retention at high frequencies.

The construction is based on the stacking of aluminum elements that includes the surface of the dielectric Al₂O₃ and the polymer counter electrode. External layers are built with carbon and silver. The construction and a photo from an element are presented in Figures 1 and 2.

Figure 1. KEMET A798 Aluminum Organic Capacitor (AO-CAP®) Basic Construction

https://content.kemet.com/datasheets/KEM_T2020_A700.pdf

Figure 2. Aluminum Element foil photo

Several foil elements are stacked and positioned within the capacitor construction. A schematic construction is shown in Figure 3. The construction offers very low ESR capabilities.

Figure 3 – Schematic Construction of A798 Plus Performance Capacitor

AO-CAP® may be operated at steady state voltages up to 100% of rated voltage without the need to de-rate. This characteristic is due to the low-stress interface with the dielectric and polymer counter electrodes and is a favorable reliability parameter.

Since there is no liquid electrolyte, the A798 offers long operational lifetimes, low ESR, and high operational temperatures.

Enhancements to the design and selected material upgrades were introduced to expand the 125ºC Life Endurance at a rated voltage of up to 3000h. In addition, the Storage Endurance is also extended to 125ºC while maintaining the humidity bias capability at 85ºC/85%RH/Ur up to 1000h

The product portfolio is limited to low-voltage power rails in typical DC/DC converters, servers, telecommunications, displays, and industrial applications. The new part numbers are described in Table 1a, and the AO-CAP selection guide summary is in Table 1b.

Table 1a. A798 Plus Performance (125ºC / 3000h) Series Initial Product Portfolio Offering.

Table 1b. AO-CAP® Selection Guideline Table.

The new A798 Plus Performance AO-CAP ® brings the Polymer Aluminum capability to extremely extended lifespan application conditions. Please contact a YAGEO Group sales representative to help with a solution for your design challenge.