KEMET, a global supplier of electronic components, has introduced its new KO-CAP Reliability Assessment method for polymer electrolytic capacitors.
Developed as a result of over ten years of research, the Reliability Assessment method utilizes accelerated voltage and temperature conditions applied to board-mounted samples of T540 and T541 commercial-off-the-shelf (COTS) capacitors to assess long-term device reliability. The failure rates available are B (0.1% per 1,000 hours), C (0.01% per 1,000 hours), and D (0.001% per 1,000 hours).
This new Reliability Assessment method complements the T540 and T541 COTS Series KO-CAPs. These capacitors are designed for decoupling and filtering applications that require very low equivalent series resistance (ESR). By utilizing an organic conductive polymer as the cathode plate of the capacitor, this technology results in low ESR, high ripple current capability, and improved capacitance retention at high frequency. Such performance characteristics are suitable for various high reliability defense and aerospace applications such as radar, sonar, power supplies, and guidance systems. KO-CAPs with the new Reliability Assessment method are available with rated voltages from 2.5 to 63 VDC, capacitances up to 1,500 µF, and ESR as low as 5 mΩ—all in surface-mount packaging.
Design engineers can now match the reliability requirements of their project to the appropriate failure rate. Traditional Weibull methods of assessing reliability are not suitable for polymer electrolytic capacitors and fall short of properly assessing lot-to-lot reliability. Prior to this release, this capability was only available through source-control drawings, but is now easy to design in by adding the desired failure rate to the 13th character of the part number.