POLYFUSE® Resettable PTCs Axial Leaded Strap ST Series Description The new ST series device provides reliable, noncycling protection against overcharging and short circuits events for rechargeable battery cells where resettable protection is desired. Features • RoHS compliant and lead-free • Low resistance • Weldable nickel terminals Agency Approvals AGENCY AGENCY FILE NUMBER • Provides overcurrent protection at 125°C trip temperature Applications E183209 •R echargeable battery cell protection R50082521 Electrical Characteristics Part Number I hold (A) I trip (A) V max (Vdc) I max (A) Pd max. (W) 15ST120 1.2 2.7 15 100 15ST120S 1.2 2.7 15 100 15ST175 1.75 3.8 15 15ST175S 1.75 3.8 15 Maximum Time To Trip Agency Approvals Resistance Current (A) Time (Sec.) R min (Ω) R typ (Ω) R 1max (Ω) 1.2 6.00 5.00 0.085 0.160 0.220 X X 1.2 6.00 5.00 0.085 0.160 0.220 X X 100 2.5 8.75 5.00 0.050 0.090 0.120 X X 100 2.5 8.75 5.00 0.050 0.090 0.120 X X I hold = Hold current: maximum current device will pass without tripping in 20°C still air. R typ = Typical resistance of device in initial (un-soldered) state. I trip = Trip current: minimum current at which the device will trip in 20°C still air. R 1max = Maximum resistance of device at 20°C measured one hour after tripping or reflow soldering of 260°C for 20 sec. V max = Maximum voltage device can withstand without damage at rated current (I max) Caution: Operation beyond the specified rating may result in damage and possible arcing and flame. I max = Maximum fault current device can withstand without damage at rated voltage (Vmax) P d = Power dissipated from device when in the tripped state at 20°C still air. R min = Minimum resistance of device in initial (un-soldered) state. ST Series Specifications are subject to change without notice. Electronics Designers Guide www.littelfuse.com ©2006 Littelfuse POLYFUSE® Resettable PTCs Axial Leaded Strap Temperature Rerating Ambient Operation Temperature -40°C -20°C 0°C 23°C Part Number 40°C 50°C 60°C 70°C 85°C Hold Current (A) 15ST120 1.90 1.70 1.50 1.20 1.00 0.90 0.80 0.70 0.50 15ST120S 1.90 1.70 1.50 1.20 1.00 0.90 0.80 0.70 0.50 15ST175 2.50 2.30 2.00 1.75 1.50 1.30 1.20 1.10 0.90 15ST175S 2.50 2.30 2.00 1.75 1.50 1.30 1.20 1.10 0.90 Average Time Current Curves Temperature Rerating Curve 170% Percentage of Rated Current 150% 130% 110% 90% 70% 50% 30% 10% -40 -30 -20 A: 15ST120/15ST120S D: B: 15ST175/15ST175S E: -10 0 10 20 30 40 Temperature (°C) 50 60 70 80 C: The average time current curves and temperature rerating curve performance is affected by a number or variables, and these curves provided as guidance only. Customer must verify the performance in their application. ST Series Specifications are subject to change without notice. Electronics Designers Guide www.littelfuse.com ©2006 Littelfuse POLYFUSE® Resettable PTCs Axial Leaded Strap Physical Specifications Environmental Specifications 0.13mm nominal thickness, quarter-hard nickel Lead Material Insulating Material Polyester tape Operating/Storage Temperature -40°C to +85°C Maximum Device Surface Temperature in Tripped State 125°C Passive Aging +70°C, 1000 hours ±5% typical resistance change Humidity Aging +85°C, 85%R.H. 7days ±5% typical resistance change Vibration MIL-STD-883C, Condition A No change Dimensions Figure 1 Figure 2 0.5 x 4.0 NOMINAL (.02”x .15”) SLIT A A Marking B E D1 Figure 1 D2 Figure 2 SLIT A A Part Number B D1 B Inches mm Marking B D1 C 0.5 x 4.0 NOMINAL (.02”x .15”) mm D2 C C A Inches Inches D1 mm E B Min. Max. Min. Max. Min. Max. Min. Marking Max. Min. Max. Min. E Max. Min. 15ST120 0.78 mm Fig. Min. Min. Min. Min Max. Min. Max. 0.22 5.5 0.22 5.5 0.01 0.22 3.9 4.1 1 1 0.22 Product Series 5.5 0.22 5.5 0.01 0.22 3.9 4.1 2 19.9 22.1 0.19 0.20 4.9 5.2 0.02 19.9 C 22.1 0.19 0.20 4.9 5.2 0.02 0.04 0.6 0.82 0.91 20.9 23.1 0.19 0.20 4.9 5.2 0.02 ST 0.04 0.6 1 0.16 4.1 Current Rating 0.16 4.1 0.01 0.16 3.9 4.1 1 15ST175S 0.82 0.91 20.9 23.1 0.19 0.20 4.9 5.2 0.02 XX9U 0.04 0.6 1 0.16 0.16 4.1 0.01 0.16 3.8 4.2 2 15ST175 D2 D1 Top Side 0.6 E Inches 0.87 15ST120S 0.78 0.04 D2 Inches mm Inches mm Marking 0.87 E D2 120 Littelfuse Trademark 1 C 4.1 Lot Number (Contact Littelfuse for additional information) Part Marking System Part Numbering System 15 ST 175 S U Top Side Product Series ST 120 XX9U Littelfuse Trademark QUANTITY CODE: U = 500 (bulk) Current Rating LEAD OPTIONS: Blank = standard S = slit lead Lot Number (Contact Littelfuse for additional information) HOLD CURRENT (VALUE DIVIDED BY 100 = HOLD CURRENT IN AMPS) SERIES VOLTAGE RATING (VDC) Packaging I hold (A) All Ratings Packaging Option Quantity Quantity & Packaging Codes Bulk 500 U ST Series Specifications are subject to change without notice. Electronics Designers Guide www.littelfuse.com ©2006 Littelfuse