![0449004.MR — Fuse, Surface Mount, 4 A, Slow Blow, 125 VAC, 125 VDC, 2410 [6125 Metric]](/media/C/1/F/72D12940CFE90F1C.webp)
0449004.MR
Fuse, Surface Mount, 4 A, Slow Blow, 125 VAC, 125 VDC, 2410 [6125 Metric]
- Manufacturer: LITTELFUSE
- Product type: SMD Fuses
- Fuse Current:4A; Product Range:NANO2 Series; Voltage Rating VAC:125VAC; Voltage Rating V DC:125VDC; Blow Characteristic:Time Delay; Fuse Case Style:SMD; Breaking Capacity Current AC:50A; Breakin
- SVHC: No SVHC (25-Jun-2020)
- Fuse Current: 4A
- Product Range: NANO2 Slo-Blo 449 Series
- Fuse Case Style: 2410 [6125 Metric]
- Voltage Rating VAC: 125VAC
- Voltage Rating VDC: 125VDC
- Blow Characteristic: Slow Blow
- Breaking Capacity Current AC: 50A
- Breaking Capacity Current DC: 50A
| Delivery and price | |
|---|---|
| Units per pack | 1000 |
| Price | 1.08 € |
| Current stock | 500+ |
| Lead time | 30 days |
**Surface Mount Fuses** NANO[2®] > Slo-Blo[®] Fuse > 449 Series **RoHS Pb PSE** ~~[_IQHF cAMus <>~~ ## 449 Series Fuse ## ~~**Description**~~ The lead free NANO[2®] Slo-Blo[®] fuse is RoHS compliant, Halogen Free and 100% lead-free. This product is fully compatible with lead-free solder alloys and higher temperature profiles associated with lead-free assembly. The Slo-Blo[®] fuse design has enhanced inrush withstand characteristics over the NANO[2®] Fast-Acting Fuse. The unique time delay feature of this fuse design helps solve the problem of nuisance “opening” by accommodating inrush currents that normally cause a fast-acting fuse to open. ## ~~**Features**~~ ## ~~**Agency Approvals**~~ - Lead-free, Halogen free • Wide operating and RoHS compliant temperature range **==> picture [499 x 469] intentionally omitted <==** **----- Start of picture text -----**<br> |||||||||||| |---|---|---|---|---|---|---|---|---|---|---| |AGENCY|AGENCY FILE NUMBER|AMPERE RANGE| |• Small size|• Low temperature| |cWAk|us|E10480|0.375A - 5A|• Wide range of current|rerating| |ratings available| |PSE|NBK030205-E10480B|1A - 5A| |Oo| |Applications| |Electrical Characteristics for Series| |Secondary protection for space constrained applications:| |% of Ampere| |Rating|Opening Time|• Notebook PC|• Storage system| |100%|4 hours, Minimum|• LCD/PDP TV|• Telecom system| |• LCD monitor|• Wireless basestation| |200%|1 sec., Min.; 60 sec., Max.| |• LCD/PDP panel|• White goods| |300%|0.2 sec., Min.; 3 sec., Max| |• LCD backlight inverter|• Game console| |800%|0.02 sec., Min.; 0.1 sec., Max.| |• Portable DVD player|• Office Automation| |equipment| |• Power supply| |Additional Information|• Battery charging circuit| |• Networking| |protection| |• PC server| |• Industrial equipment| |• Cooling fan system| |kd| |Datasheet|Resources|Samples| |Electrical Specifcations by Item| |Ampere|Max|Nominal Cold|Nominal|pO|Agency Approvals| |Voltage|Interrupting| |Rating(A)|Amp Code|Rating|Rating|Resistance (Ohms)|I|[2]|Melting t (A|[2]|sec)|PSE| |(V)| |0.375|.375|125|1.5130|0.088|x| |a|a|ee|eee| |0.500|.500|125|0.7633|0.258|x| |a|es| |0.750|.750|125|0.4080|0.847|x| |a|ee ee| |1.00|001.|125|0.2516|1.76|x|x| |a|a|ee| |ee|es| |1.50|01.5|125|0.1186|4.70|x|x| |a|50A @125 VAC/VDC|ee|ee| |2.00|002.|125|0.0708|6.76|x|x| |a|aesee| |PSE: 100A @100 VAC| |2.50|02.5|125|0.0400|13.18|x|x| |a|ee|ee| |3.00|003.|125|0.0352|19.55|x|x| |a|a|ee| |ee|es| |3.50|03.5|125|0.0261|32.70|x|x| |a|ee|ee| |4.00|004.|125|0.0227|40.80|x|x| |a|a|eeee| |5.00|005.|125|0.0171|59.59|x|x| |a|rree|ee| **----- End of picture text -----**<br> Notes: - l[2] t calculated at 8ms. Resistance is measured at 10% of rated current, 25ºC © 2016 Littelfuse, Inc. Specifications are subject to change without notice. Application testing is strongly recommended. Revised: 10/10/16 **Surface Mount Fuses** NANO[2®] > Slo-Blo[®] Fuse > 449 Series **==> picture [94 x 32] intentionally omitted <==** **==> picture [261 x 19] intentionally omitted <==** **----- Start of picture text -----**<br> Temperature Re-rating Curve<br>**----- End of picture text -----**<br> **==> picture [261 x 19] intentionally omitted <==** **----- Start of picture text -----**<br> Average Time Current Curves<br>**----- End of picture text -----**<br> **==> picture [245 x 324] intentionally omitted <==** **----- Start of picture text -----**<br> 1000<br>100<br>10<br>1<br>0.1<br>0.01<br>0 1 10 100<br>CURRENT IN AMPERES<br>.375A .500A .750A 1A 1.5A2A 2.5A 3A3.5A 4A 5A<br>TIME IN SECONDS<br>**----- End of picture text -----**<br> **==> picture [243 x 197] intentionally omitted <==** Note: 1. Rerating depicted in this curve is in addition to the standard derating of 25% for continuous operation. **==> picture [523 x 281] intentionally omitted <==** **----- Start of picture text -----**<br> ||||||||||| |---|---|---|---|---|---|---|---|---|---| |Soldering Parameters| |Reflow Condition|Pb – Free assembly|t|P| |T|P| |Critical Zone| |- Temperature Min (Ts(min))|150°C|Ramp-up|TL to TP| |Pre Heat|- Time (Min to Max) (t- Temperature Max (Ts(max)s)|)|200°C60 – 120 secs|T|S(max)|T|L|t|L| |Average ramp up rate (Liquidus Temp|3°C/second max.|Preheat|Ramp-down| |(TL) to peak|T|S(min)| |TS(max) to TL - Ramp-up Rate|3°C/second max.|t|S| |Reflow|- Temperature (TL) (Liquidus)|217°C|25| |- Temperature (tL)|60 – 90 seconds|time to peak temperature|Time| |(t 25ºC to peak)| |Peak Temperature (TP)|260|[+0/–5]|°C| |Time within 5°C of actual peak| |20 – 40 seconds| |Temperature (tp)| |Ramp-down Rate|5°C/second max.| |Time 25°C to peak Temperature (TP)|8 minutes max.| |Do not exceed|260°C| |260°C Peak| |Wave Soldering Parameters|Temperature,| |3|seconds max.| **----- End of picture text -----**<br> © 2016 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 10/10/16 **Surface Mount Fuses** NANO[2®] > Slo-Blo[®] Fuse > 449 Series **==> picture [93 x 32] intentionally omitted <==** ## ~~**Product Characteristics**~~ ||**Materials**|**Body:**Ceramic<br>**Terminations:**Gold-plated Caps|| |---|---|---|---| ||**Product Marking**|Brand, Amperage Rating|| ||**Operating**<br>**Temperature**<br>**Moisture**<br>**Sensitivity Level**|-55°C to 125°C<br>Level 1, J-STD-020|| ||**Solderability**|MIL-STD-202, Method 208|| ||**Insulation**<br>**Resistance (after**<br>**Opening)**|MIL-STD-202, Method 302, Test Condition<br>A (10,000 ohms minimum)|| ||||| ||~~**Dimensions**~~||| **==> picture [246 x 161] intentionally omitted <==** **----- Start of picture text -----**<br> MIL-STD-202, Method 107, Test<br>Thermal Shock Condition B, 5 cycles, -65°C to<br>125°C, 15 minutes @ each extreme<br>MIL-STD-202, Method 213, Test I:<br>Deenergized. 100G’s pk amplitude,<br>Mechanical Shock<br>sawtooth wave 6ms duration, 3<br>cycles XYZ+xyz = 18 shocks<br>MIL-STD-202, Method 201: 0.03"<br>Vibration amplitude, 10-55 Hz in 1 min. 2hrs<br>each XYZ=6hrs<br>Moisture Resistance MIL-STD-202, Method 106, 10 cycles<br>MIL-STD-202, Method 101, Test<br>Salt Spray<br>Condition B (48hrs)<br>Resistance to Soldering MIL-STD-202, Method 210, Test<br>Heat condition B (10 sec at 260°C)<br>**----- End of picture text -----**<br> **==> picture [261 x 19] intentionally omitted <==** **----- Start of picture text -----**<br> Part Numbering System<br>**----- End of picture text -----**<br> **==> picture [522 x 236] intentionally omitted <==** **----- Start of picture text -----**<br> 0449 001. M R<br>6.86 6.10 ± .20<br>(.270") (.240") SERIES<br>3.15 1 A AMP Code *<br>(.124") F T Refer to Electrical charac-<br>teristics table<br>1.45<br>2.95 (.057") QUANTITY Code<br>1.96 (.116") M = 1000 pcs<br>(.077") 2.69 ± .25<br>PACKAGING Code<br>Recommended pad layout (.106")<br>R = Tape and Reel<br>2.69 ± .25 *Example:<br>(.106") 0.375 Amp product is 0449 .375 MR<br>(1 amp product shown above).<br>Packaging<br>Quantity &<br>Packaging Option Packaging Specification Quantity<br> Packaging Code<br>12mm Tape and Reel EIA RS-481-2 (IEC 286, part 3) 1000 MR<br>**----- End of picture text -----**<br> © 2016 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 10/10/16
Updated at June 9, 2026
Founded in 1927 and headquartered in Chicago, Illinois, Littelfuse is a premier global manufacturer of circuit protection, power control, and sensing technologies. Widely recognized for pioneering the first small, fast-acting protective fuse, the company has grown into an industry leader whose highly reliable components are essential to modern industrial, transportation, and consumer electronics applications worldwide. At the core of the Littelfuse portfolio is an expansive and industry-leading range of circuit protection solutions. This encompasses a massive selection of traditional fuses, fuse holders, and resettable PTC thermistor fuses designed to safely interrupt overcurrent conditions. To defend against electrical overstress, Littelfuse also provides advanced transient voltage suppression (TVS) technologies, including thousands of specialized TVS diodes, TVS varistors, and gas discharge tubes (GDTs) that ensure robust defense against voltage spikes and environmental hazards. Beyond its foundational protection components, Littelfuse manufactures a diverse array of discrete semiconductors, sensors, and switching devices. Engineers rely on their high-performance thyristors, including TRIACs and SCRs, alongside power-efficient Schottky diodes and MOSFETs for demanding power control applications. Complemented by precision proximity sensors and highly reliable reed and solid-state relays, Littelfuse delivers the critical building blocks required for secure, efficient, and complete system design.
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