KEMET T491B686K010AT4280

KEMET T491B686K010AT4280 Tantalum SMD Capacitor Summary and Features

The KEMET T491B686K010AT4280 is an industrial-grade molded tantalum surface mount capacitor, part of the well-established T491 series. Designed to meet the stringent requirements of automated assembly lines, the device represents a modern standard for high-performance and reliable solid tantalum capacitors. The T491B686K010AT4280 features a capacitance value of 68 μF with a tolerance of ±10%, rated at 10 V DC, and is offered in a compact 1411 (3528 metric) low-profile molded case. This capacitor is intended for general-purpose applications, including decoupling and filtering circuits in sectors such as portable electronics, telecommunications, power management modules, and control units.

Primary Electrical Specifications of T491B686K010AT4280

Selection of capacitors for practical circuits requires attention to detailed parameters. The T491B686K010AT4280 presents the following notable electrical characteristics:

Capacitance: 68 μF, making it suitable for moderate-to-high bulk energy storage or filtering roles.

Rated Voltage: 10 V DC, ensuring compatibility with low-voltage digital and power designs.

Capacitance Tolerance: ±10% (alternative options available across the series).

ESR (Equivalent Series Resistance): 10 Ω, facilitating stable ripple current and low noise performance in switching power supplies and filtering applications.

Operating Temperature: -55°C to +125°C, making it suitable for industrial environments with robust thermal requirements.

Performance Lifetime: 2,000 hours at 125°C, supporting long-term reliability objectives in embedded designs.

Moisture Sensitivity Level (MSL): MSL 1, meaning unlimited floor life under industry-standard moisture sensitivity testing.

Design, Composition, and Durability Features of T491B686K010AT4280

The T491B686K010AT4280 employs KEMET’s proven solid MnO₂ (manganese dioxide) cathode technology in a robust molded case. This design choice addresses industry needs for reliability, achieving compliance with or exceeding EIA Standard 535BAAC. All standard models are RoHS and REACH compliant, with lead-free matte tin or optional gold-plated terminations. The halogen-free epoxy meets UL94 V-0 flammability and passes ASTM E595 outgassing tests, enhancing suitability for sensitive or critical electronic assemblies.

Symmetrical and compliant terminations, laser-marked cases, and the option of surge-current testing for several case sizes further enhance the reliability and traceability of this series. The capacitor’s physical dimensions are 3.50 mm x 2.80 mm with a maximum seated height of 2.10 mm, supporting dense and low-profile PCB layouts.

Procedures for Soldering, Integration, and Packaging of T491B686K010AT4280

The T491B686K010AT4280 is engineered for full compatibility with modern soldering processes, including convection, infrared (IR), vapor phase reflow, and wave solder techniques (case size permitting). These devices can withstand up to three reflow passes at IPC/J-STD-020D profile temperatures, critical for boards requiring multiple soldering cycles (e.g., double-sided assemblies).

KEMET packages these devices in tape and reel configurations per EIA 481 guidelines, compatible with high-speed pick-and-place equipment. The robust packaging specification details cover tape leader/trailer lengths, peel strength, and rotation/lateral limits, minimizing the risk of misplacements or defects during automated assembly.

Environmental Regulations and Certifications of T491B686K010AT4280

As an industry-standard tantalum capacitor, T491B686K010AT4280 carries complete compliance credentials:

RoHS 3 (Directive 2002/95/EC): Lead-free, halogen-free, and no hazardous substances present.

REACH unaffected, indicating no substances of concern.

Epoxy molding material certified flame-retardant and compliant with outgassing requirements (ASTM E595).

MSL1 (per J-STD-020): Devices are resistant to moisture-induced failures, allowing flexible storage and handling during production.

These credentials support use in global manufacturing and production environments.

Practical Uses and Engineering Solutions with T491B686K010AT4280

Typical applications for the T491B686K010AT4280 include use as a bulk storage, decoupling, and noise filtering capacitor in DC/DC converters, portable digital devices, RF modules, telecommunications baseband units, and industrial control PCBs. The device’s low ESR and stable temperature behavior make it well-suited to power rails sensitive to ripple-induced errors or where board height and placement density are constrained.

The compact size and low-profile construction offer strategic advantages in miniaturized end-equipment, while the robust environmental and reliability ratings address the needs of extended temperature and demanding system-level qualification.

Essential Engineering Considerations for T491B686K010AT4280 Ripple Current, Voltage Derating, and Storage

Proper application of the T491B686K010AT4280 maximizes reliability. Designers must adhere to:

Ripple Current/Voltage Limits: The allowable AC ripple (current/voltage) is constrained by ESR and power dissipation limits; the sum of DC bias and positive peak AC voltage must not exceed device voltage rating. Reverse voltage is permitted for transients only and should not become a permanent operating condition.

Derating: Conventional best practice recommends operating below maximum rated voltage, especially at elevated temperatures, to ensure long-term device integrity.

Storage: Store within 40°C and 60% relative humidity; avoid corrosive atmospheres. Consumable stock should ideally be used within three years to maintain ideal solderability.

Alternative or Substitute Options Comparable to T491B686K010AT4280

When considering alternative sourcing or second sourcing, engineers and procurement personnel may evaluate the following within the T491 series or similar surface mount tantalum capacitor series, ensuring electrical and mechanical equivalency:

Other KEMET T491 series models with the same capacitance (68 μF), voltage rating (10 V), and 1411 (3528 metric) package. Variations may include different terminations (matte tin, gold-plated, or SnPb solder-coated as required by process compatibility).

Industry-standard equivalents from other manufacturers’ surface mount tantalum lines that match on capacitance, voltage, temperature range, ESR, and package outline.

It remains essential to cross-check ESR, physical size, terminations, and environmental compliance during substitution, particularly when used in sensitive or safety-critical systems.

Conclusion

The KEMET T491B686K010AT4280 embodies a comprehensive solution for designers demanding reliable, space-efficient, and high-performance surface mount capacitors. Its proven solid tantalum technology, robust environmental compliance, and compatibility with high-volume manufacturing create significant advantages for integration into industrial, telecom, and consumer applications. Through careful observance of recommended ripple, derating, and assembly guidelines, the T491B686K010AT4280 can deliver predictable long-term operation. For sourcing flexibility, a clear understanding of the series and equivalency within KEMET’s or the wider market’s tantalum offerings allows secure, production-ready design choices.