MF-R020-AP Polymeric PTC Resettable Fuse - Equivalent & Substitute Parts

Part Overview

The MF-R020-AP is an active polymeric PTC resettable fuse manufactured by Bourns Inc. in the Multifuse® MF-R series. This component provides overcurrent protection at 60V with a 200 mA hold current rating in a through-hole radial disc package. The part is ROHS3 compliant and carries cURus and TUV approvals. Finding equivalent substitute parts is necessary when the primary part is unavailable, when lead times require alternative sourcing, or when design flexibility permits selection from qualified alternatives meeting identical electrical and mechanical specifications.

Substiute Parts

MF-R020-AP

Bourns Inc.In Stock: 2268MF-R020-AP Datasheet

Current PartRFQ

RXEF017-AP

LittelfuseIn Stock: 1385RXEF017-AP Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MF-R020-AP is determined by the following critical parameters:

• Voltage rating must equal or exceed 60V maximum
• Current hold (Ih) rating must be compatible with circuit protection requirements
• Current trip (It) rating must provide appropriate overcurrent response
• Mounting type must be through-hole to maintain PCB compatibility
• Package form must be radial disc to ensure mechanical fit within board layout constraints
• Operating temperature range must encompass -40°C to 85°C minimum
• RoHS3 compliance and recognized safety certifications (cURus, TUV, UL, CSA) are required for regulatory equivalence

The RXEF017-AP from Littelfuse meets these substitution criteria with compatible voltage, mounting, package, temperature, and compliance specifications, though with a lower hold current rating of 170 mA.

Parameter Comparison

Engineering Selection Recommendations

The RXEF017-AP qualifies as a substitute for the MF-R020-AP based on matching voltage rating, operating temperature range, mounting configuration, package form, and regulatory compliance status. Both parts are ROHS3 compliant and carry recognized safety certifications.

Selection between these parts depends on circuit-specific requirements:

• Use MF-R020-AP when the 200 mA hold current and 400 mA trip current are specified design parameters and lower initial resistance (1.5 Ohms) is required for minimal voltage drop during normal operation.

• Use RXEF017-AP when the lower 170 mA hold current and 340 mA trip current provide adequate protection for the target application, and when the broader certification portfolio (CQC, CSA, TUV, UL) aligns with regional regulatory requirements. The higher initial resistance (3.3 Ohms) and slower trip time (3 s) must be evaluated against circuit tolerance specifications.

Both parts are active products with current inventory availability.

Frequently Asked Questions (FAQ)

Q: Can RXEF017-AP be used as a direct drop-in replacement for MF-R020-AP?

A: Mechanical and electrical compatibility exists for PCB mounting. However, the RXEF017-AP has a lower hold current (170 mA vs. 200 mA) and lower trip current (340 mA vs. 400 mA). Verify that your circuit design tolerates these lower protection thresholds before substitution.

Q: What is the difference in initial resistance between these parts?

A: The MF-R020-AP has an initial resistance of 1.5 Ohms minimum, while the RXEF017-AP is rated at 3.3 Ohms minimum. Higher initial resistance increases voltage drop during normal circuit operation. Evaluate this impact on your power budget and signal integrity requirements.

Q: Are the physical dimensions compatible?

A: Yes. Both parts are radial disc packages with 0.291" diameter. The thickness differs by 0.004" (0.10mm), and lead spacing differs by 0.002" (0.05mm). These differences are within standard PCB layout tolerances for through-hole components.

Q: Which certifications does each part carry?

A: The MF-R020-AP carries cURus and TUV approvals. The RXEF017-AP carries CQC, CSA, TUV, and UL approvals. If your application requires specific regional certifications, verify that the substitute part meets those requirements.

Q: What is the impact of the different trip times?

A: The MF-R020-AP trips in 2.2 seconds, while the RXEF017-AP trips in 3 seconds. The slower response time of the RXEF017-AP may affect overcurrent protection speed. Confirm that your circuit design accommodates this difference in fault response timing.

Q: Are both parts currently available?

A: Yes. The MF-R020-AP has 2208 pieces in stock, and the RXEF017-AP has 1325 pieces in stock as new original inventory.