CMF-SD35-10-2 Equivalent & Substitute Parts

Part Overview

The CMF-SD35-10-2 is a ceramic PTC resettable fuse manufactured by Bourns Inc., rated for 230V (600V internal) with a 100 mA hold current. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing design support and procurement continuity. The part operates as a thermal protection device, automatically resetting after fault conditions are cleared, and is packaged in a 4-SMD cube surface mount configuration suitable for compact circuit board applications.

Substiute Parts

CMF-SD35-10-2

Bourns Inc.In Stock: 1121CMF-SD35-10-2 Datasheet

Current PartRFQ

CMF-SDP35A-2

Bourns Inc.In Stock: 7953CMF-SDP35A-2 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for PTC resettable fuses is determined by the following critical parameters:

• Voltage Rating: The substitute must meet or exceed the maximum voltage specification (230V / 600V internal)
• Current Hold (Ih): The substitute's hold current must be compatible with the circuit's normal operating current
• Current Trip (It): The trip threshold must provide appropriate fault protection
• Resistance: Equivalent resistance minimizes circuit behavior changes
• Package and Mounting: Physical compatibility with existing PCB layouts
• Time to Trip: Response time consistency for protection coordination

The CMF-SDP35A-2 qualifies as a substitute based on matching voltage rating, equivalent resistance, identical time-to-trip specification, and compatible 4-SMD cube packaging. The substitute maintains the same thermal protection characteristics while offering active product status and improved availability.

Parameter Comparison

Engineering Selection Recommendations

The CMF-SDP35A-2 is the qualified substitute for the obsolete CMF-SD35-10-2 based on the following engineering criteria:

Voltage and Protection Characteristics: Both components maintain identical 230V (600V internal) ratings and 200 ms trip time, ensuring equivalent circuit protection performance.

Electrical Parameters: The CMF-SDP35A-2 exhibits a 10 mA higher hold current (110 mA vs. 100 mA) and 30 mA higher trip current (230 mA vs. 200 mA), representing acceptable operational variance within PTC fuse design tolerances. The maximum current rating of 2.5 A (versus 3 A) requires verification against circuit maximum fault current specifications.

Compliance and Availability: The substitute maintains ROHS3 compliance and MSL-1 rating, matching the original component's environmental and handling requirements. Active product status ensures long-term procurement availability and manufacturing support.

Physical Compatibility: The 4-SMD cube package remains identical, with the substitute offering a smaller footprint (8.75mm x 7.20mm versus 10.20mm x 9.00mm) and reduced thickness (10.20mm versus 10.80mm), providing layout flexibility without requiring PCB redesign.

Frequently Asked Questions (FAQ)

Q: Can the CMF-SDP35A-2 directly replace the CMF-SD35-10-2 without circuit modification?

A: Yes, for circuits where the maximum fault current does not exceed 2.5 A. The voltage rating, resistance, and trip time are identical. Verify that the circuit's maximum fault current specification does not exceed the substitute's 2.5 A maximum rating.

Q: What is the significance of the 10 mA difference in hold current?

A: The CMF-SDP35A-2 hold current of 110 mA versus the original 100 mA represents a 10% increase. This remains within acceptable PTC fuse design tolerances and does not affect circuit protection function. Normal operating current must remain below the hold current threshold in both cases.

Q: Does the smaller physical size of the CMF-SDP35A-2 affect performance?

A: No. The reduced footprint (8.75mm x 7.20mm versus 10.20mm x 9.00mm) and thickness (10.20mm versus 10.80mm) do not impact electrical performance. The smaller size may provide PCB layout advantages without requiring design changes.

Q: Are there compliance or certification differences between the two parts?

A: Both components are ROHS3 compliant with MSL-1 moisture sensitivity ratings. The CMF-SDP35A-2 carries active product status, ensuring continued manufacturing support and availability, whereas the CMF-SD35-10-2 is obsolete.

Q: What should be verified before implementing the substitute?

A: Confirm that the circuit's maximum fault current specification does not exceed 2.5 A. Verify that normal operating current remains below 110 mA to ensure the substitute's hold current is not exceeded during normal operation.