A700 Plus Performance AO-CAP® Aluminum Polymer SMD Capacitor

Extended Mission Profiles in Telecom Lead to New AO-CAP® Lifespan Qualification Capability: 125ºC/Ur/3000h

High demand in power management and miniaturization requirements combined with high-temperature profiles over the lifespan are today’s challenges that designers need to solve. KEMET is expanding the AO-CAP ® Aluminum Polymer SMD capacitor, introducing the 125ºC /3000h capability in the A700 Series. KEMET enhanced the product offering 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 A700 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 frequency.

The construction is based on the stacking of aluminum elements, including the dielectric Al₂O₃ and the polymer counter electrode on the surface. 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 A700 Aluminum Organic Capacitor (AO-CAP) Basic Construction

Figure 2. Aluminum Element Foil Photo

Several element foils are stacked and positioned within the capacitor construction, a schematic of the construction is shown in Figure 3. Due to its construction, it has very low ESR capabilities.

Figure 3 – Schematic Construction of A700 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 electrode and is a favorable reliability parameter.

Since there is no liquid electrolyte, the A700 offers long operational lifetimes, low ESR, and high operational temperatures.

The ESR in frequency shows a broader curve with values < 10mOhm and minimal variation with temperature. Go here to access the K-SIM for A700 .

Enhancements to the design and selected material upgrades were introduced to expand the 125ºC Life Endurance at rated voltage up to 3000h. In addition, the Storage Endurance was also extended to 125ºC.

The initial product portfolio is limited to one part number suitable to support 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 in Table 1b.

Table 1a. A700 Plus Performance (125ºC / 3000h) Series Initial Product Portfolio Offering

Table 1b. AO-CAP Selection Guideline Table

The high 470 μF capacitance combined with the low and stable ESR contributes to the application's performance, allowing a higher ripple.

The KEMET A700 Plus Performance qualification procedures specify tight acceptance criteria for capacitance drift, dissipation factor, ESR, and DCL, as described in Table 2.

Table 2. A700 Plus Performance (125ºC / 3000h) - Qualification Acceptance Criteria

In addition, current inline verification, such as five-time surface mount reflow at 260ºC according to the JEDEC Std 020D, reveals excellent ESR stability, Figure 4.

Figure 4. A700 Plus Performance – Inline 5x 260ºC SMT – ESR Stability Verification

Conclusion

The new A700 Plus Performance AO-CAP brings the Polymer Aluminum capability to extreme extended lifespan application conditions. Contact a sales representative to help find a solution to your design challenge.