T494B685K025AS Equivalent & Substitute Parts

Part Overview

The T494B685K025AS is a 6.8 µF molded tantalum capacitor rated at 25 V with a 1411 (3528 Metric) package footprint. Manufactured by KEMET in the T494 series, this component is classified as obsolete. The part features a 2 Ohm equivalent series resistance (ESR), ±10% capacitance tolerance, and operates across a temperature range of -55°C to 125°C with a 2000-hour lifetime specification at 125°C.

Due to the obsolete status of the T494B685K025AS, equivalent and substitute parts from active product lines are necessary to maintain design continuity and ensure long-term component availability. Suitable alternatives are available from KEMET, Vishay Sprague, and KYOCERA AVX, all meeting the core electrical and mechanical specifications required for direct substitution.

Substiute Parts

T494B685K025AS

KEMETIn Stock: 824T494B685K025AS Datasheet

Current PartRFQ

T494B685K025AT

KEMETIn Stock: 8495T494B685K025AT Datasheet

DirectRFQ

T491B685K025AT

KEMETIn Stock: 9168T491B685K025AT Datasheet

SimilarRFQ

293D685X9025B2TE3

Vishay SpragueIn Stock: 3370293D685X9025B2TE3 Datasheet

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TAJB685K025RNJ

KYOCERA AVXIn Stock: 1188TAJB685K025RNJ Datasheet

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TPSB685K025R0700

KYOCERA AVXIn Stock: 10507TPSB685K025R0700 Datasheet

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TR3B685K025C0400

Vishay SpragueIn Stock: 2872TR3B685K025C0400 Datasheet

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TR3B685K025C0500

Vishay SpragueIn Stock: 690TR3B685K025C0500 Datasheet

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TR3B685K025C0700

Vishay SpragueIn Stock: 1014TR3B685K025C0700 Datasheet

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TR3B685K025C1200

Vishay SpragueIn Stock: 1175TR3B685K025C1200 Datasheet

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TR3B685K025C1500

Vishay SpragueIn Stock: 1053TR3B685K025C1500 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the T494B685K025AS is determined by strict adherence to the following core parameters:

Critical Parameters (Must Match Exactly):

• Capacitance: 6.8 µF
• Tolerance: ±10%
• Voltage Rating: 25 V
• Package / Case: 1411 (3528 Metric)
• Type: Molded Tantalum
• Mounting Type: Surface Mount
• Operating Temperature Range: -55°C to 125°C
• Moisture Sensitivity Level: 1 (Unlimited)
• RoHS Status: ROHS3 Compliant

Variable Parameters (Allowed to Differ):

• ESR (Equivalent Series Resistance): Ranges from 400 mOhm to 2.8 Ohm across substitute options
• Packaging Format: Cut Tape (CT), Digi-Reel®, or Tape & Reel (TR)
• Manufacturer: KEMET, Vishay Sprague, or KYOCERA AVX
• Product Status: Active (preferred over obsolete)

All substitute parts listed maintain identical electrical performance within the specified tolerance and voltage parameters. Variations in ESR do not affect functional compatibility in general-purpose applications. Packaging format differences relate only to procurement and handling, not circuit performance.

Parameter Comparison

Engineering Selection Recommendations

Primary Recommendation: T494B685K025AT

The T494B685K025AT is the direct equivalent to the obsolete T494B685K025AS. Both parts are from the KEMET T494 series and share identical electrical specifications: 6.8 µF capacitance, ±10% tolerance, 25 V rating, and 2 Ohm ESR. The T494B685K025AT is currently in active production status, ensuring long-term availability. The only difference is packaging format (Tape & Reel versus bulk), which does not affect circuit performance. This part is ROHS3 compliant and maintains the same MSL rating of 1 (Unlimited).

Secondary Recommendations: KEMET T491B685K025AT

The T491B685K025AT from KEMET's T491 series provides an alternative within the same manufacturer ecosystem. It maintains all critical electrical parameters with the exception of ESR, which is specified at 2.8 Ohm compared to the original 2 Ohm. This ESR variation remains within acceptable tolerances for general-purpose applications. The part is active and ROHS3 compliant.

Alternative Manufacturers: Vishay Sprague and KYOCERA AVX

Vishay Sprague TANTAMOUNT™ series (TR3 variants) and KYOCERA AVX series (TAJ and TPS variants) offer multiple options with varying ESR specifications. All alternatives maintain the core electrical parameters of 6.8 µF, ±10% tolerance, and 25 V rating. These parts are all active in production and ROHS3 compliant. Selection among these alternatives depends on ESR requirements specific to the application circuit.

Compliance Status:

All substitute parts listed are ROHS3 compliant, REACH unaffected, and classified under ECCN EAR99. All maintain MSL rating of 1 (Unlimited), indicating no moisture sensitivity restrictions during storage or handling.

Frequently Asked Questions (FAQ)

Q: Can T494B685K025AT be used as a direct replacement for T494B685K025AS?

A: Yes. The T494B685K025AT is electrically and mechanically identical to the T494B685K025AS. Both parts have 6.8 µF capacitance, ±10% tolerance, 25 V rating, 2 Ohm ESR, and 1411 (3528 Metric) package footprint. The primary difference is that T494B685K025AT is in active production while T494B685K025AS is obsolete. Packaging format differs (Tape & Reel versus bulk), but this does not affect circuit performance.

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

A: ESR (Equivalent Series Resistance) affects the impedance characteristics of the capacitor at high frequencies and influences ripple current handling. Substitute parts range from 400 mOhm to 2.8 Ohm ESR. For general-purpose applications, these variations are functionally compatible. Applications with specific ESR requirements should select parts matching the original 2 Ohm specification or verify that alternative ESR values meet circuit performance criteria.

Q: Are all substitute parts suitable for the same operating temperature range?

A: Yes. All substitute parts listed operate across the -55°C to 125°C temperature range, matching the original T494B685K025AS specification. All parts are rated for 2000-hour lifetime at 125°C, ensuring consistent thermal performance.

Q: What packaging format differences exist among substitute parts?

A: Substitute parts are available in three packaging formats: Tape & Reel (TR), Cut Tape (CT) with Digi-Reel®, and bulk. These differences relate to procurement, handling, and automated assembly compatibility. They do not affect electrical performance or circuit functionality. Selection should be based on manufacturing process requirements and inventory management practices.

Q: Are all substitute parts RoHS compliant?

A: Yes. All substitute parts listed are ROHS3 compliant and REACH unaffected. Compliance certifications are identical across all alternatives, ensuring regulatory compatibility in applications requiring RoHS certification.

Q: Can substitute parts from different manufacturers be mixed in the same design?

A: Yes. All substitute parts meet identical electrical specifications for capacitance, tolerance, voltage rating, and operating temperature. They share the same 1411 (3528 Metric) package footprint and surface mount configuration. Parts from KEMET, Vishay Sprague, and KYOCERA AVX are functionally interchangeable within the specified parameters.

Q: What is the MSL rating and why is it important?

A: All substitute parts carry an MSL (Moisture Sensitivity Level) rating of 1 (Unlimited), identical to the original part. This rating indicates that the components have no moisture sensitivity restrictions during storage or handling. No special moisture control measures are required during procurement, storage, or assembly.

Q: How should ESR selection be determined for a specific application?

A: ESR selection depends on circuit requirements. The original T494B685K025AS specifies 2 Ohm ESR. Direct equivalent T494B685K025AT maintains this specification. Alternative parts with lower ESR (400 mOhm to 1.5 Ohm) provide improved high-frequency performance and reduced ripple current effects. Parts with higher ESR (2.4 Ohm to 2.8 Ohm) remain functionally compatible for general-purpose filtering applications. Circuit analysis should determine whether ESR variation affects performance.