Axial Lead & Cartridge Fuses PICO® ll > Very Fast-Acting Fuse > 251/253 Series 251/253 Series, PICO® II Very Fast-Acting Fuse PS E QPL Description The PICO® II Very Fast-Acting Fuse is designed to meet an extensive array of performance characteristics in a space-saving subminiature package. Features • Very fast-acting • Halogen-free available • Small size • Wide operating temperature range • Wide current rating range (0.062A- 15A) • Low temperature re-rating Applications Agency Approvals Agency File Agency Number Secondary protection for space constrained applications Agency File Number 251 Series 253 Series PS E QPL Ampere Range • Flat–panel display TV • Power supply • LCD monitor • Audio/Video system N/A E10480 0.062A - 15A • LCD backlight inverter • Lighting system N/A 29862 0.062A - 15A • Office machines • Medical equipment N/A JET1896-310071004 1A - 5A N/A J50158379 0.500A - 10A FM10 N/A 0.062A - 15A N/A 2009010207366577 0.500A, 1A, 2A, 2.5A, 3A, 4A, 5A Electrical Characteristics for Series % of Ampere Rating Ampere Rating Opening Time 100% 0.062A - 15A 4 Hours, Min. 200% 275% Additional Information 400% Datasheet 251 Series Resources 251 Series Samples 251 Series Datasheet 253 Series Resources 253 Series Samples 253 Series © 2015 Littelfuse, Inc. Specifications are subject to change without notice. Application testing is strongly recommended. Revised: 11/11/15 1000% 0.062A - 7A 1 Second, Max. 10A 3 Seconds, Max. 12 - 15A 10 Seconds, Max. 0.500A, 1A, 2A, 2.5A, 3A, 4A, 5A, 7A, 10A 0.05A, 1A, 2A, 2.5A, 3A, 4A, 5A, 7A, 10A 0.500A, 1A, 2A, 2.5A, 3A, 4A, 5A, 7A, 10A 300 msecs., Max. 30 msecs., Max. 4 msecs., Max. Axial Lead & Cartridge Fuses PICO® ll > Very Fast-Acting Fuse > 251/253 Series Electrical Specifications by Item Agency Approvals Nom Max Nominal Ampere Nominal Ordering Ordering Voltage Amp Voltage Interrupting Cold Rating Melting Number Number Drop Code Rating Rating Resistance 2 (A) I t (A2 sec) (Std.) (Mil.) (V) (V) (Ohms) .062 .125 .200 .250 .375 .500 .630 .750 1.00 1.25 1.50 2.00 2.50 3.00 3.50 4.00 5.00 7.00 10.0 12.0 15.0 .062 .125 .200 .250 .375 .500 .630 .750 001. 1.25 01.5 002. 02.5 003. 03.5 004. 005. 007. 010. 012. 015. 251.062 251.125 251.200 251.250 251.375 251.500 251.630 251.750 251001. 2511.25 25101.5 251002. 25102.5 251003. 25103.5 251004. 251005. 251007. 251010. 251012. 251015. 253.062 253.125 253.200 253.250 253.375 253.500 253.750 253001. 25301.5 253002. 253003. 253004. 253005. 253007. 253010. 253015. 125 125 125 125 125 125 125 125 125 125 125 125 125 125 125 125 125 125 125 32 32 300 A @ 125VDC 50A@125VAC For CCC 7A: 70A@125VAC For CCC 10A: 100A@ 125VAC 300A@32VDC & 50A@32VAC 7.000 1.700 0.895 0.665 0.395 0.302 0.205 0.175 0.128 0.100 0.0823 0.0473 0.0360 0.0295 0.0240 0.0204 0.0158 0.0107 0.0072 0.0059 0.00446 0.000113 0.00174 0.0048 0.0116 0.0296 0.0598 0.08 0.153 0.256 0.390 0.587 0.405 0.721 1.19 1.58 2.45 4.14 10.4 25.5 45.2 68.8 1.4 0.285 0.345 0.24 0.215 0.2165 0.188 0.176 0.194 0.2 0.21 0.141 0.132 0.131 0.1205 0.114 0.11 0.102 0.1 0.0878 0.071 PS E QPL TUV 253 Series Only x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x Note: Higher ampere ratings are available. Please contact Littelfuse Technical Support or your Littelfuse products representative for assistance. © 2015 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 11/11/15 Axial Lead & Cartridge Fuses PICO® ll > Very Fast-Acting Fuse > 251/253 Series .250A .375A .500A .630A .750A 1A 1.25A 1.5A 2A 2.5A 3A 3.5A 4A 5A 7A 10A 12A 15A 100 .125A Average Time Current Curves .062A Temperature Re-rating Curve TIME IN SECONDS 10 1 0.1 Note: 1. Re-rating depicted in this curve is in addition to the standard derating of 25% for continuous operation. 0.01 Soldering Parameters Recommended Process Parameters: Lead-Free Recommendation for 251 Series only Wave Parameter Preheat: (Depends on Flux Activation Temperature) (Typical Industry Recommendation) Temperature Minimum: 100°C Temperature Maximum: Preheat Time: 150°C 60-180 seconds Solder Pot Temperature: 260°C Maximum Solder Dwell Time: 2-5 seconds Recommended Hand Soldering Parameters: Solder Iron Temperature: 350°C +/- 5°C Heating Time: 5 seconds max. Note: These devices are not recommended for IR or Convection Reflow process © 2015 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 11/11/15 0.001 0.05 0.1 1 10 CURRENT IN AMPERES 100 1000 Axial Lead & Cartridge Fuses PICO® ll > Very Fast-Acting Fuse > 251/253 Series Product Characteristics Vibration MIL-STD-202, Method 201 (10–55 Hz); Method 204, Test Condition C (55–2000 Hz at 10 G’s Peak) MIL-STD-202, Method 211, Test Condition A (will withstand a 7lbs. axial pull test) Shock MIL-STD-202, Method 213, Test Condition I (100 G’s peak for 6 msecs.) Fuses To MIL SPEC For fuses to MIL-PRF-23419, FM10 change the series number from 251 to 253 Insulation Resistance (After Opening): MIL-STD-202, Method 302, Test Condition A (10,000 ohms minimum at 100 volts) Operating Temperature –55ºC to +125ºC (Consider re-rating) Moisture Resistance MIL-STD-202, Method 106 Resistance to Soldering Heat Withstands 60 seconds above 200OC and up to 260ºC, maximum Flammability Rating UL 94V–0 Materials Encapsulated, Epoxy-Coated Body: Pure Tin-coated Copper wire leads Solderability MIL-STD-202, Method 208 Lead Pull Force Part Numbering System Dimensions 251 Series Markings (T1 lead length) 62.7 (2.468") 52.4 (2.062")* 27.78 (1.094") 7.11 (.280") 1A 6.35 (.25") tape LF 5.0 (.197") 1A 0251 xxxx N R T1 L Series 27.78 (1.094") 2.80 (.11") MAX 251 = Standard type 253 = Military type 6.35 (.25") tape LF N = 5000 P = 2000 M = 1000 H = 100 251 Series (Halogen-free Version) Markings 27.78 (1.094") 6.35 (.25") tape 7.11 (.280") LF 1A 1A LF 27.78 (1.094") 2.80 (.11") MAX 5.0 (.197") Type of Packaging 6.35 (.25") tape 253 Series Markings (T3 lead length) 83.31 (3.28") 6.35 (.25") tape 73.0 (2.874")** 7.11 (.280") LF 1A LF 1A Lead Length Option Codes 38.1 (1.5") 2.61 (.103") MAX 5.0 (.197") R = Reel A = Ammo Pack X = Loose Pack The default lead length for Ammo pack and Loose pack is now T1 for 251 series, and remains T3 for 253 series, therefore: T1 = 52.4mm (2.062”), 251 series only* Blank = 52.4mm (2.062”) for 251 series* or 73mm (2.874”) for 253 series** Wire Diameter: 0.64 (.025") for 0.62-10.0 amp, 0.81 (.032") for 12-15 amp 38.1 (1.5") Refer to Amp Code column of Electrical Specifications Table Quantity Wire Diameter: 0.64 (.025") for 0.62-10.0 amp, 0.81 (.032") for 12-15 amp (T1 lead length) 62.7 (2.468") 52.4 (2.062")* Current Rating L = RoHS + HF (Only applies to 251 Series) 6.35 (.25") tape Wire Diameter: 0.64 (.025") for 0.62-10.0 amp, 0.81 (.032") for 15 amp Packaging Packaging Option Packaging Specification *T1: 52.4mm (2.062") Tape and Reel EIA 296 **T3: 73mm (2.874') Tape and Reel EIA 296 Quantity & Packaging Code Please refer to available quantities above in "Part Numbering System” The default lead length for both ammo pack and loose pack is T1 for 251 and is T3 for 253. Notes: * T1 dimension is defined as the length of the component between the two tapes. The full component length is 62.7mm (2.468"). T1 length is for 251 series only. ** T3 dimension is defined as the length of the component between the two tapes. The full component length is 83.3.7mm (3.28”). T3 length is for 253 series only. © 2015 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 11/11/15