MF-RHT450-AP Equivalent & Substitute Parts

Part Overview

The MF-RHT450-AP is a polymeric PTC resettable fuse manufactured by Bourns Inc. in the Multifuse® series. This component provides overcurrent protection with a 16V maximum voltage rating and 4.5A hold current specification. The device is designed for through-hole radial mounting in disc configuration and is currently in active production status. Equivalent and substitute parts are identified when component availability is limited, supply chain disruptions occur, or design flexibility permits selection from qualified alternatives meeting the same electrical and mechanical requirements.

Substiute Parts

MF-RHT450-AP

Bourns Inc.In Stock: 701MF-RHT450-AP Datasheet

Current PartRFQ

RGEF600-1

LittelfuseIn Stock: 1630RGEF600-1 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

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

Voltage rating must equal or exceed the maximum voltage specification (16V minimum required). Current hold rating must be compatible with circuit protection requirements; the substitute RGEF600-1 provides 6A hold current, which exceeds the 4.5A specification of the main part. Current trip and maximum current ratings establish the protective response envelope. Resistance characteristics (initial and post-trip) define circuit behavior during normal operation and fault conditions. Operating temperature range must encompass the application environment. Mounting type and package configuration must be identical (through-hole radial disc) to ensure mechanical and electrical compatibility. RoHS compliance status must be maintained for regulated applications.

The RGEF600-1 from Littelfuse meets these substitution criteria with matching voltage rating, compatible current ratings, equivalent mounting configuration, and identical RoHS3 compliance status.

Parameter Comparison

Engineering Selection Recommendations

Both the MF-RHT450-AP and RGEF600-1 maintain active product status and ROHS3 compliance. The MF-RHT450-AP is rated for extended operating temperature range (-40°C to 125°C) compared to the RGEF600-1 (-40°C to 85°C). Selection between these parts depends on application temperature requirements. The RGEF600-1 provides lower initial resistance (10 mOhms versus 22 mOhms) and lower post-trip resistance (28 mOhms versus 54 mOhms), resulting in reduced circuit losses during normal operation and faster thermal recovery after trip events. The RGEF600-1 holds CSA, TUV, and UL certifications, while the MF-RHT450-AP carries AEC-Q200 rating for automotive applications. Component selection should align with specific application certifications and thermal environment constraints.

Frequently Asked Questions (FAQ)

Q: Can RGEF600-1 directly replace MF-RHT450-AP in all applications?

A: Direct substitution is valid when the application operating temperature does not exceed 85°C. The MF-RHT450-AP is required for applications operating above 85°C due to its extended temperature rating to 125°C.

Q: What is the impact of different hold current ratings (4.5A vs 6A)?

A: The RGEF600-1 with 6A hold current provides broader protection margin. Circuits designed for 4.5A hold current will operate within the RGEF600-1 specification. The higher rating does not compromise protection; it establishes a higher threshold before device activation.

Q: How do resistance differences affect circuit performance?

A: The RGEF600-1 exhibits lower initial and post-trip resistance values. This reduces voltage drop during normal operation and accelerates thermal recovery after a trip event. For applications sensitive to circuit losses, the RGEF600-1 provides improved efficiency.

Q: Are packaging and lead spacing identical?

A: Both components use through-hole radial disc configuration. Lead spacing differs: MF-RHT450-AP has 0.114" (2.90mm) spacing while RGEF600-1 has 0.199" (5.05mm) spacing. PCB layout must accommodate the specific lead spacing of the selected component.

Q: Which certifications apply to each part?

A: MF-RHT450-AP carries AEC-Q200 automotive qualification. RGEF600-1 holds CSA, TUV, and UL certifications. Application requirements determine which certification set is necessary.