T491C685M025AS Equivalent & Substitute Parts

Part Overview

The T491C685M025AS is a 6.8 µF molded tantalum capacitor manufactured by KEMET, rated for 25 V operation in a 2312 (6032 Metric) surface mount package. This component is classified as obsolete, indicating that direct procurement from the original manufacturer may be limited or unavailable. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain reliability, and support ongoing production or repair requirements for applications utilizing this capacitor specification.

Substiute Parts

T491C685M025AS

KEMETIn Stock: 1033T491C685M025AS Datasheet

Current PartRFQ

T491C685M025AT

KEMETIn Stock: 1214T491C685M025AT Datasheet

DirectRFQ

TAJC685M025RNJ

KYOCERA AVXIn Stock: 2664TAJC685M025RNJ Datasheet

DirectRFQ

293D685X0025C2TE3

Vishay SpragueIn Stock: 9257293D685X0025C2TE3 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the T491C685M025AS is determined by strict equivalence across the following critical parameters:

Electrical Parameters:

• Capacitance: 6.8 µF (exact match required)
• Tolerance: ±20% (exact match required)
• Voltage Rating: 25 V (exact match required)
• ESR: Within acceptable range for the application (1.7 Ohm to 2.0 Ohm)

Mechanical Parameters:

• Package / Case: 2312 (6032 Metric) (exact match required)
• Mounting Type: Surface Mount (exact match required)
• Physical Dimensions: 0.236" L x 0.126" W, Height ≤ 0.110" (exact match required)

Environmental Parameters:

• Operating Temperature Range: -55°C ~ 125°C (exact match required)
• Moisture Sensitivity Level: 1 (Unlimited) (exact match required)

Substitute parts must satisfy all electrical, mechanical, and environmental parameters. Compliance certifications (RoHS, REACH) and product status (Active vs. Obsolete) are secondary considerations that support long-term availability and regulatory compliance.

Parameter Comparison

Engineering Selection Recommendations

T491C685M025AT (KEMET)

This part is the direct equivalent to T491C685M025AS with identical electrical and mechanical specifications. The primary distinction is product status: T491C685M025AT is Active, whereas the main part is Obsolete. T491C685M025AT is RoHS3 compliant and carries a lifetime rating of 2000 Hrs @ 125°C. The packaging format is Tape & Reel (TR), supporting automated assembly processes. This part is the preferred substitute when KEMET sourcing is required or when design continuity within the T491 series is prioritized.

TAJC685M025RNJ (KYOCERA AVX)

This part meets all electrical and mechanical requirements with an ESR of 2.0 Ohm, which is within acceptable tolerance of the main part's 1.9 Ohm specification. TAJC685M025RNJ is Active and RoHS3 compliant. The TAJ series from KYOCERA AVX provides cross-manufacturer compatibility while maintaining identical package geometry and electrical performance. This part is suitable for applications where multi-source qualification is required or when KYOCERA AVX supply chain access is advantageous.

293D685X0025C2TE3 (Vishay Sprague)

This part satisfies all electrical and mechanical parameters with an ESR of 1.7 Ohm, which is lower than the main part's 1.9 Ohm specification. The 293D series (TANTAMOUNT™) from Vishay Sprague is Active and RoHS3 compliant. The lower ESR characteristic may provide performance benefits in applications sensitive to impedance characteristics. This part is suitable for designs requiring Vishay Sprague sourcing or when lower ESR performance is beneficial.

All three substitute parts are electrically and mechanically interchangeable with T491C685M025AS. Selection among substitutes should be based on supply chain availability, manufacturing qualification requirements, and compliance certifications applicable to the end application.

Frequently Asked Questions (FAQ)

Q: Can T491C685M025AT be used as a direct replacement for T491C685M025AS?

A: Yes. T491C685M025AT is electrically and mechanically identical to T491C685M025AS. Both parts share the same capacitance (6.8 µF), voltage rating (25 V), tolerance (±20%), ESR (1.9 Ohm), package (2312 / 6032 Metric), and operating temperature range (-55°C ~ 125°C). The primary difference is that T491C685M025AT is Active status with RoHS3 compliance, whereas T491C685M025AS is Obsolete and RoHS non-compliant.

Q: What is the significance of ESR differences among the substitute parts?

A: ESR (Equivalent Series Resistance) affects impedance characteristics and heat dissipation in the capacitor. The main part specifies 1.9 Ohm. TAJC685M025RNJ has 2.0 Ohm ESR (0.1 Ohm higher), and 293D685X0025C2TE3 has 1.7 Ohm ESR (0.2 Ohm lower). These variations are within normal manufacturing tolerances for tantalum capacitors and do not affect functional compatibility in general-purpose applications. Applications with strict impedance requirements should verify ESR specifications against circuit design parameters.

Q: Are all substitute parts RoHS compliant?

A: T491C685M025AT, TAJC685M025RNJ, and 293D685X0025C2TE3 are all RoHS3 compliant. The main part T491C685M025AS is RoHS non-compliant. If RoHS compliance is a regulatory requirement for the end application, any of the three substitute parts satisfy this requirement.

Q: Do the substitute parts have identical physical dimensions?

A: Yes. All substitute parts conform to the 2312 (6032 Metric) package specification with dimensions of 0.236" L x 0.126" W (6.00mm x 3.20mm) and maximum seated height of 0.110" (2.80mm). The 293D685X0025C2TE3 specifies a maximum height of 0.110" (2.79mm), which is within the tolerance band and does not affect PCB layout compatibility.

Q: What is the Moisture Sensitivity Level (MSL) for these parts?

A: All parts, including the main part and all substitutes, are rated MSL 1 (Unlimited). This classification indicates that the components have unlimited shelf life and do not require special moisture control during storage or handling.

Q: Can these parts be used interchangeably in automated assembly?

A: Yes. All parts are surface mount components in Tape & Reel (TR) packaging format, suitable for automated pick-and-place assembly. The identical package geometry ensures compatibility with existing PCB designs and assembly equipment programming.

Q: Which substitute part should be selected for new designs?

A: For new designs, T491C685M025AT, TAJC685M025RNJ, or 293D685X0025C2TE3 are all acceptable choices. Selection should be based on: (1) supply chain availability and lead time, (2) manufacturing qualification status within your organization, (3) preferred vendor relationships, and (4) any application-specific performance requirements related to ESR characteristics. All three parts are Active status with current availability.