FEMTOSMDC035F-02 Equivalent & Substitute Parts

Part Overview

The FEMTOSMDC035F-02 is a polymeric PTC resettable fuse manufactured by Littelfuse Inc. in the PolySwitch® femtoSMD series. This surface mount component is rated for 6V maximum voltage with a 350 mA hold current and is housed in a 0603 (1608 Metric) package with concave geometry. The part is active in production and widely stocked, with 37,100 units available in inventory. PTC resettable fuses are essential circuit protection devices that automatically reset after a fault condition is cleared, eliminating the need for manual replacement and reducing system downtime in electronic applications.

Substiute Parts

FEMTOSMDC035F-02

Littelfuse Inc.In Stock: 37209FEMTOSMDC035F-02 Datasheet

Current PartRFQ

0603L035YR

LittelfuseIn Stock: 431640603L035YR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FEMTOSMDC035F-02 is determined by strict electrical and mechanical compatibility criteria. The following parameters must remain constant or within acceptable tolerances:

Critical Matching Parameters:

• Voltage rating: 6V maximum
• Current hold rating: 350 mA
• Package type: 0603 (1608 Metric), Concave
• Mounting type: Surface Mount
• Operating temperature range: -40°C ~ 85°C
• RoHS compliance: ROHS3 Compliant

The substitute part 0603L035YR meets all critical electrical parameters and maintains identical package geometry and mounting characteristics, making it a direct functional equivalent for circuit protection applications requiring these specifications.

Parameter Comparison

Engineering Selection Recommendations

Both the FEMTOSMDC035F-02 and 0603L035YR are active production components from Littelfuse Inc. with full ROHS3 compliance. The FEMTOSMDC035F-02 carries CSA and UL approvals, while the 0603L035YR carries cURus and TUV approvals. Selection between these parts should be based on the specific regulatory requirements of the target application and end-use market. Both components are suitable for 6V circuit protection applications requiring 350 mA hold current operation in 0603 surface mount packages. The 0603L035YR offers slightly lower initial resistance (200 mOhms versus 280 mOhms) and marginally higher trip current (750 mA versus 700 mA), which may provide enhanced performance in applications with tighter tolerance requirements.

Frequently Asked Questions (FAQ)

Q: Can the 0603L035YR directly replace the FEMTOSMDC035F-02 in existing designs?

A: Yes. Both components share identical voltage ratings (6V), hold current specifications (350 mA), package geometry (0603 Concave), and operating temperature ranges (-40°C ~ 85°C). The electrical and mechanical compatibility is complete for direct substitution in surface mount applications.

Q: What is the difference in trip current between these parts?

A: The FEMTOSMDC035F-02 has a trip current of 700 mA, while the 0603L035YR has a trip current of 750 mA. This 50 mA difference is within normal manufacturing tolerance ranges for PTC resettable fuses and does not affect functional compatibility in standard circuit protection applications.

Q: Are the approval certifications interchangeable?

A: The FEMTOSMDC035F-02 carries CSA and UL certifications, while the 0603L035YR carries cURus and TUV certifications. Selection should align with the specific regulatory requirements of your target market and application. Both certifications are recognized standards for circuit protection components.

Q: What is the significance of the initial resistance difference?

A: The FEMTOSMDC035F-02 has a minimum initial resistance of 280 mOhms, while the 0603L035YR has a minimum of 200 mOhms. Lower initial resistance reduces voltage drop during normal operation, which may be beneficial in power-sensitive applications. Both values are within acceptable ranges for 350 mA rated fuses.

Q: Are both parts available in the same packaging format?

A: The FEMTOSMDC035F-02 is available in standard packaging, while the 0603L035YR is supplied in Tape & Reel (TR) format. Both maintain identical 0603 (1608 Metric) Concave package geometry suitable for automated surface mount assembly processes.