Littelfuse 0453.750MR Surface Mount Board Mount Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 0453.750MR is a 750 mA, 125 V AC/DC surface mount board mount fuse in the NANO²® 453 series. This fast-blow fuse is designed for circuit protection in applications requiring 2-SMD, square end block packaging with a 50A breaking capacity at rated voltage. The part is active in production and widely available in inventory (10,200 pcs).

Equivalent and substitute parts are identified when design requirements necessitate alternative sourcing due to inventory constraints, supply chain considerations, or specific application parameters that align with the main part's electrical and mechanical specifications.

Substiute Parts

0453.750MR

Littelfuse Inc.In Stock: 102530453.750MR Datasheet

Current PartRFQ

0448.750MR

Littelfuse Inc.In Stock: 73420448.750MR Datasheet

Parametric EquivalentRFQ

0451.750MRL

Littelfuse Inc.In Stock: 552290451.750MRL Datasheet

Parametric EquivalentRFQ

0451.750NRL

Littelfuse Inc.In Stock: 100720451.750NRL Datasheet

Parametric EquivalentRFQ

SF-2410FP075T-2

Bourns Inc.In Stock: 2761SF-2410FP075T-2 Datasheet

DirectRFQ

SF-2410HI075T-2

Bourns Inc.In Stock: 9089SF-2410HI075T-2 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the Littelfuse 0453.750MR are grouped into two categories based on electrical and mechanical compatibility:

Parametric Equivalents (Littelfuse Series): Parts 0448.750MR, 0451.750MRL, and 0451.750NRL share identical electrical ratings (750 mA, 125 V AC/DC, fast-blow response), mechanical packaging (2-SMD, square end block), and approval certifications (CSA, UL). These parts differ only in internal melting I²t characteristics and DC cold resistance values, which remain within acceptable tolerance ranges for the same application class. All operate across the same temperature range (-55°C ~ 125°C) and maintain 50A breaking capacity.

Direct Manufacturer Alternatives (Bourns Series): Parts SF-2410FP075T-2 and SF-2410HI075T-2 from Bourns Inc. are cross-manufacturer substitutes meeting identical electrical specifications (750 mA, 125 V AC/DC, fast-blow) and mechanical form factor (2-SMD, square end block). These parts carry cUL and UL certifications and operate within the same temperature range. Dimensional variations are minimal (0.102" W x 0.102" H versus 0.106" W x 0.106" H), maintaining PCB layout compatibility.

Parameter Comparison

Engineering Selection Recommendations

All listed substitute parts maintain active product status and meet the core electrical and mechanical requirements of the 0453.750MR. Selection among equivalents should be based on the following criteria:

Littelfuse Parametric Equivalents: The 0451.750MRL offers the highest inventory availability (55,200 pcs) with identical melting I²t (0.185) and DC cold resistance (0.245 Ohms) to the main part, making it the primary substitute within the Littelfuse product line. The 0451.750NRL provides equivalent electrical performance with moderate inventory (10,016 pcs). The 0448.750MR differs slightly in melting I²t (0.206) and DC cold resistance (0.2475 Ohms) but remains within the same application class.

Bourns Cross-Manufacturer Alternatives: Both Bourns parts carry cUL and UL certifications equivalent to the Littelfuse CSA/UL approvals. The SF-2410FP075T-2 and SF-2410HI075T-2 differ in melting I²t characteristics (0.3761 and 1.2632 respectively), reflecting different thermal response profiles. These parts are suitable for applications where cross-manufacturer qualification has been completed and thermal response variations are acceptable within the circuit design.

Frequently Asked Questions (FAQ)

Q: Can the 0451.750MRL be used as a direct replacement for the 0453.750MR?

A: Yes. Both parts share identical current rating (750 mA), voltage ratings (125 V AC/DC), response time (fast-blow), breaking capacity (50A), melting I²t (0.185), DC cold resistance (0.245 Ohms), and operating temperature range (-55°C ~ 125°C). The primary difference is the series designation (NANO²® 451 versus NANO²® 453). Both carry CSA and UL certifications.

Q: What is the significance of the melting I²t parameter in selecting a substitute?

A: Melting I²t defines the thermal energy required to melt the fuse element and is critical for circuit protection coordination. The 0453.750MR has a melting I²t of 0.185. Substitutes with identical or very similar values (0451.750MRL and 0451.750NRL at 0.185, 0448.750MR at 0.206) provide equivalent protection characteristics. Bourns alternatives with higher melting I²t values (0.3761 and 1.2632) represent different thermal response profiles and require application-level verification.

Q: Are the Bourns SF-2410 series parts compatible with the same PCB layout?

A: The Bourns parts have slightly smaller dimensions (0.102" W x 0.102" H) compared to the Littelfuse parts (0.106" W x 0.106" H). Both maintain the 0.240" length and 2-SMD, square end block package format. PCB footprints designed for the Littelfuse 0453.750MR will accommodate the Bourns alternatives, though verification of solder pad alignment is recommended.

Q: What certifications apply to each substitute part?

A: Littelfuse parts (0453.750MR, 0448.750MR, 0451.750MRL, 0451.750NRL) carry CSA and UL certifications. Bourns parts (SF-2410FP075T-2, SF-2410HI075T-2) carry cUL and UL certifications. All parts are ROHS3 compliant and REACH unaffected or affected as specified.

Q: Which substitute offers the best inventory availability?

A: The 0451.750MRL from Littelfuse offers the highest inventory level at 55,200 pcs, compared to 10,016 pcs for the 0451.750NRL and 7,271 pcs for the 0448.750MR. Among Bourns alternatives, the SF-2410HI075T-2 provides 9,025 pcs and the SF-2410FP075T-2 provides 2,683 pcs.