MF-USMD035-2 Equivalent & Substitute Parts

Part Overview

The MF-USMD035-2 is a Polymeric PTC Resettable Fuse manufactured by Bourns Inc., rated for 6V maximum voltage with 350 mA hold current. This component is classified as Obsolete, which necessitates identification of active equivalent parts for ongoing design and procurement requirements. The part operates across a temperature range of -40°C to 85°C and is housed in a 1210 (3225 Metric) surface mount package.

Substiute Parts

MF-USMD035-2

Bourns Inc.In Stock: 999MF-USMD035-2 Datasheet

Current PartRFQ

MF-USMF035-2

Bourns Inc.In Stock: 38437MF-USMF035-2 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MF-USMD035-2 is determined by strict equivalence across the following critical electrical and mechanical parameters:

Electrical Parameters: Voltage rating (6V), hold current (350 mA), trip current (750 mA), maximum current (40 A), time to trip (200 ms), initial resistance (200 mOhms minimum), and post-trip resistance (1.3 Ohms maximum).

Mechanical Parameters: Surface mount mounting type, 1210 (3225 Metric) package footprint, and dimensional compatibility (0.127" L x 0.102" W).

Functional Type: Polymeric PTC resettable fuse technology.

The substitute part MF-USMF035-2 meets all electrical specifications and maintains mechanical compatibility within the specified package class. Dimensional variations in thickness (0.033" vs. 0.024") and package geometry (Concave configuration) represent acceptable mechanical tolerances for the 1210 package family and do not affect electrical performance or circuit board integration.

Parameter Comparison

Engineering Selection Recommendations

The MF-USMF035-2 is the direct active equivalent for the obsolete MF-USMD035-2. Both parts are manufactured by Bourns Inc. within the Multifuse® PTC resettable fuse family and maintain identical electrical performance across all critical parameters: 6V voltage rating, 350 mA hold current, 750 mA trip current, 200 ms trip time, and resistance specifications.

The MF-USMF035-2 offers improved compliance status: it carries ROHS3 certification compared to the non-compliant status of the MF-USMD035-2, and includes AEC-Q200 automotive qualification. Both parts maintain CSA and TUV approvals with equivalent regulatory standing.

Mechanical compatibility is confirmed across the 1210 (3225 Metric) package family. The thickness variation (0.033" maximum for MF-USMF035-2 versus 0.024" for MF-USMD035-2) remains within standard package tolerances and does not affect PCB assembly or circuit integration.

For new designs or component refresh cycles, the MF-USMF035-2 is the specified replacement, offering active product status and enhanced environmental compliance.

Frequently Asked Questions (FAQ)

Q: Can MF-USMF035-2 be used as a direct replacement for MF-USMD035-2 in existing designs?

A: Yes. Both parts share identical electrical specifications (6V, 350 mA hold current, 750 mA trip current, 200 ms trip time) and are housed in compatible 1210 (3225 Metric) surface mount packages. The thickness difference (0.033" vs. 0.024") falls within standard package tolerances and does not affect PCB layout or assembly.

Q: What is the difference between the MF-USMD and MF-USMF series?

A: Both series are Multifuse® polymeric PTC resettable fuses from Bourns Inc. The MF-USMF series represents the active product line with current manufacturing status and enhanced compliance certifications (ROHS3, AEC-Q200), while the MF-USMD series is obsolete. Electrical performance is equivalent across rated specifications.

Q: Are there packaging differences between these parts?

A: The MF-USMF035-2 is supplied in Tape & Reel (TR) packaging, while the MF-USMD035-2 packaging format is not specified. Both parts use the same 1210 (3225 Metric) footprint. The MF-USMF035-2 features a Concave package geometry, a standard variation within the 1210 package class.

Q: Does the thickness difference affect circuit board design?

A: No. The maximum thickness of 0.033" (0.85mm) for MF-USMF035-2 compared to 0.024" (0.62mm) for MF-USMD035-2 remains within the tolerance band for 1210 (3225 Metric) surface mount components and does not require PCB layout modifications.

Q: What compliance certifications apply to the substitute part?

A: The MF-USMF035-2 carries cURus and TUV approvals, ROHS3 compliance, and AEC-Q200 automotive qualification. The original MF-USMD035-2 holds CSA, TUV, and UR approvals with RoHS non-compliant status. Both maintain REACH Unaffected status.