T494B686M006AS Equivalent & Substitute Parts Reference

Part Overview

The T494B686M006AS is a 68 µF molded tantalum capacitor manufactured by KEMET, rated for 6.3 V with ±20% tolerance and 650 mOhm equivalent series resistance (ESR). This component is housed in a 1411 (3528 Metric) surface mount package and operates across the temperature range of -55°C to 125°C with a 2000-hour lifetime rating at 125°C.

The T494B686M006AS is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements. Substitute parts must maintain electrical compatibility across capacitance, voltage rating, tolerance, and physical dimensions while accommodating variations in ESR and packaging format.

Key Parameters

Parameter	Value	Unit	Substitution Criticality
Capacitance	68	µF	Critical
Voltage Rating	6.3	V	Critical
Tolerance	±20%	%	Critical
Type	Molded Tantalum	—	Critical
Package / Case	1411 (3528 Metric)	—	Critical
ESR	650	mOhm	Application-Dependent
Operating Temperature Range	-55 to 125	°C	Critical
Mounting Type	Surface Mount	—	Critical
RoHS Status	ROHS3 Compliant	—	Regulatory
MSL Rating	1 (Unlimited)	—	Handling

Substitute Part Grouping Explanation

Substitution of the T494B686M006AS is governed by strict electrical and mechanical compatibility requirements. All substitute parts must satisfy the following criteria:

Critical Matching Parameters:

Capacitance: 68 µF (exact match required)
Voltage Rating: 6.3 V (exact match required)
Tolerance: ±20% (exact match required)
Package / Case: 1411 (3528 Metric) (exact match required)
Mounting Type: Surface Mount (exact match required)
Operating Temperature Range: -55°C to 125°C (exact match required)
Type: Molded Tantalum (exact match required)

Variable Parameters (Application-Dependent):

ESR (Equivalent Series Resistance): Varies across substitute parts from 250 mOhm to 1.8 Ohm. Selection depends on circuit requirements for ripple current handling and thermal performance.
Packaging Format: Bulk or Tape & Reel (TR). Format selection depends on manufacturing and assembly processes.
Manufacturer: KEMET, Vishay Sprague, or KYOCERA AVX. All manufacturers provide ROHS3 compliance and MSL 1 rating.

Substitute parts are grouped into three categories: Direct Equivalent (same series, active status), Upgraded Tolerance (tighter tolerance specification), and Cross-Manufacturer Alternatives (different manufacturers, same electrical specifications).

Parameter Comparison

Part Number	Manufacturer	Series	Capacitance (µF)	Voltage (V)	Tolerance (%)	ESR (mOhm/Ohm)	Package	Status	Inventory (Pcs)
T494B686M006AS	KEMET	T494	68	6.3	±20	650 mOhm	1411 (3528)	Obsolete	942
T494B686M006AT	KEMET	T494	68	6.3	±20	650 mOhm	1411 (3528)	Active	2100
T494B686K006AT	KEMET	T494	68	6.3	±10	650 mOhm	1411 (3528)	Active	899
T491B686M006AT	KEMET	T491	68	6.3	±20	900 mOhm	1411 (3528)	Active	5200
293D686X06R3B2TE3	Vishay Sprague	293D	68	6.3	±20	1.8 Ohm	1411 (3528)	Active	7125
593D686X06R3B2TE3	Vishay Sprague	593D	68	6.3	±20	550 mOhm	1411 (3528)	Active	971
TACT686M006RTA	KYOCERA AVX	TAC	68	6.3	±20	1 Ohm	1411 (3528)	Active	933
TAJB686M006RNJ	KYOCERA AVX	TAJ	68	6.3	±20	900 mOhm	1411 (3528)	Active	4150
TAJB686M006Y	KYOCERA AVX	TAJ	68	6.3	±20	900 mOhm	1411 (3528)	Active	715
TPSB686M006R0250	KYOCERA AVX	TPS	68	6.3	±20	250 mOhm	1411 (3528)	Active	39200
TPSB686M006R0350	KYOCERA AVX	TPS	68	6.3	±20	350 mOhm	1411 (3528)	Active	1145

Engineering Selection Recommendations

Direct Equivalent (Recommended Primary Choice):

T494B686M006AT is the direct equivalent to the obsolete T494B686M006AS. Both parts are from the KEMET T494 series with identical electrical specifications: 68 µF capacitance, 6.3 V rating, ±20% tolerance, and 650 mOhm ESR. The T494B686M006AT is active in production with 2100 units in stock. This part requires only packaging format change from bulk to Tape & Reel (TR), which is a standard manufacturing accommodation. ROHS3 compliance and MSL 1 rating are maintained.

Upgraded Tolerance Alternative:

T494B686K006AT offers tighter ±10% tolerance while maintaining all other electrical and physical specifications of the T494B686M006AS. This part is suitable for applications requiring improved capacitance accuracy. Product status is active with 899 units available. Selection of this part introduces no compatibility risk but provides enhanced performance margin.

Cross-Manufacturer Alternatives:

Vishay Sprague 593D686X06R3B2TE3 and KYOCERA AVX TPSB686M006R0250 and TPSB686M006R0350 are functionally equivalent across all critical parameters. ESR variations (550 mOhm, 250 mOhm, and 350 mOhm respectively) must be evaluated against circuit ripple current and thermal dissipation requirements. All alternatives maintain ROHS3 compliance and MSL 1 rating. Inventory availability is strong across all alternatives.

Selection Criteria Based on Product Status and Compliance:

All substitute parts listed are active in production and ROHS3 compliant. The T494B686M006AT is the lowest-risk substitution path due to series continuity with the original part. Cross-manufacturer alternatives are suitable when supply constraints or cost optimization require diversification. ESR selection should be driven by circuit performance requirements, not availability.

Frequently Asked Questions (FAQ)

Q: Can T494B686M006AT directly replace T494B686M006AS in existing designs?

A: Yes. T494B686M006AT is electrically and mechanically identical to T494B686M006AS. The only difference is packaging format (Tape & Reel versus bulk). Both parts have 68 µF capacitance, 6.3 V rating, ±20% tolerance, 650 mOhm ESR, and 1411 (3528 Metric) package dimensions. No circuit modifications are required.

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

A: ESR (Equivalent Series Resistance) affects ripple current handling and thermal performance. Lower ESR values (250–550 mOhm) reduce heat generation and support higher ripple currents. Higher ESR values (900 mOhm to 1.8 Ohm) are suitable for lower-frequency applications with minimal ripple current. Circuit design requirements determine acceptable ESR range. The original T494B686M006AS specifies 650 mOhm; substitutes with 550 mOhm or 250 mOhm provide improved performance, while 900 mOhm or 1 Ohm alternatives are acceptable for equivalent or less demanding applications.

Q: Are cross-manufacturer parts (Vishay Sprague, KYOCERA AVX) compatible with KEMET designs?

A: Yes, provided all critical parameters match: 68 µF capacitance, 6.3 V rating, ±20% tolerance, 1411 (3528 Metric) package, and surface mount configuration. All listed manufacturers provide ROHS3 compliance and MSL 1 rating. Cross-manufacturer substitution introduces no electrical or regulatory risk when parameters are identical. Qualification testing may be required per internal design standards.

Q: What is the difference between T494B686M006AT and T494B686K006AT?

A: Both parts are KEMET T494 series with identical physical and electrical specifications except tolerance. T494B686M006AT has ±20% tolerance (matching the original T494B686M006AS). T494B686K006AT has ±10% tolerance, providing tighter capacitance accuracy. The ±10% variant is suitable for applications requiring improved performance margin or tighter circuit specifications. ESR, voltage rating, package, and temperature range are identical.

Q: Why does T491B686M006AT have higher ESR (900 mOhm) than T494B686M006AS (650 mOhm)?

A: T491 and T494 are different KEMET series with different internal construction. While both meet the 68 µF / 6.3 V / ±20% specification and 1411 package requirement, the T491 series exhibits higher ESR. This part is suitable for applications where ESR is not a limiting factor. If ripple current or thermal performance is critical, the T494B686M006AT or lower-ESR alternatives (593D686X06R3B2TE3, TPSB686M006R0250) are preferred.

Q: What does MSL 1 (Unlimited) mean for handling and storage?

A: MSL (Moisture Sensitivity Level) 1 indicates the component has unlimited shelf life and requires no special moisture control during storage or handling. No baking or desiccant packaging is required. All substitute parts listed carry MSL 1 rating, ensuring identical handling requirements to the original T494B686M006AS.

Q: Is ROHS3 compliance maintained across all substitute parts?

A: Yes. All substitute parts listed are ROHS3 compliant, matching the regulatory status of the original T494B686M006AS. No compliance risk is introduced by substitution.

Q: Which substitute part offers the best inventory availability?

A: TPSB686M006R0250 (KYOCERA AVX TPS series) has the highest inventory with 39,200 units in stock. This part is suitable for high-volume production requirements and offers low ESR (250 mOhm) for applications requiring superior ripple current performance.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message