Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Lxx04xx & Qxx04xx Series (R) Description 4 Amp bi-directional solid state switch series is designed for AC switching and phase control applications such as motor speed and temperature modulation controls, lighting controls, and static switching relays. Sensitive type devices guarantee gate control in Quadrants I & IV needed for digital control circuitry. Standard type devices normally operate in Quadrants I & III triggered from AC line. Features & Benefits * RoHS Compliant Agency Approval Agency * Glass - passivated junctions Agency File Number * Voltage capability up to 1000 V L Package : E71639 (R) * Surge capability up to 55 A Main Features Symbol IT(RMS) VDRM /VRRM IGT (Q1) Value Unit 4 A 400 to 1000 V 3 to 25 mA * Electrically isolated "L-Package" is UL recognized for 2500Vrms * Solid-state switching eliminates arcing or contact bounce that create voltage transients * No contacts to wear out from reaction of switching events * Restricted (or limited) RFI generation, depending on activation point of sine wave * Requires only a small gate activation pulse in each half-cycle Applications Schematic Symbol Typical applications are AC solid-state switches, power tools, home/brown goods and white goods appliances. MT2 Sensitive gate Triacs can be directly driven by microprocessor or popular opto-couplers/isolators. MT1 Internally constructed isolated packages are offered for ease of heat sinking with highest isolation voltage. G Absolute Maximum Ratings -- Sensitive Triacs (4 Quadrants) Symbol Parameter RMS on-state current (full sine wave) IT(RMS) ITSM Lxx04Ly / Lxx04Dy TC = 85C Lxx04Ry / Lxx04Vy TC = 75C Non repetitive surge peak on-state current (full cycle, TJ initial = 25C) I2t I2t Value for fusing Value Unit 4 A f = 50 Hz t = 20 ms 33 f = 60 Hz t = 16.7 ms 40 tp = 8.3 ms A 6.6 A2s 50 A/s Critical rate of rise of on-state current (IG = 50mA with 0.1s rise time) f = 120 Hz TJ = 110C IGTM Peak gate trigger current tp 10 s TJ = 110C 1.2 A PG(AV) Average gate power dissipation TJ = 110C 0.3 W Storage temperature range -40 to 150 C Operating junction temperature range -40 to 110 C di/dt Tstg TJ Note: xx = voltage, y = sensitivity Lxx04xx & Qxx04xx Series 51 Revised: June 24, 2011 04:57 PM (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Absolute Maximum Ratings -- Standard Triacs Symbol Parameter RMS on-state current (full sine wave) IT(RMS) ITSM Non repetitive surge peak on-state current (full cycle, TJ initial = 25C) I2t I2t Value for fusing Value Unit 4 A Qxx04Ly / Qxx04Dy TC = 95C Qxx04Ry / Qxx04Vy TC = 85C f = 50 Hz t = 20 ms 46 f = 60 Hz t = 16.7 ms 55 tp = 8.3 ms A 12.5 A2s di/dt Critical rate of rise of on-state current (IG = 50mA with 0.1s rise time) f = 120 Hz TJ = 125C 50 A/s IGTM Peak gate trigger current tp 10 s; IGT IGTM TJ = 125C 1.2 A PG(AV) Average gate power dissipation TJ = 125C 0.3 W Storage temperature range -40 to 150 C Operating junction temperature range -40 to 125 C Tstg TJ Note: xx = voltage, y = sensitivity Electrical Characteristics (TJ = 25C, unless otherwise specified) -- Sensitive Triac (4 Quadrants) Symbol IGT Test Conditions Quadrant I - II - III VD = 12V RL = 60 IV VGT VGD VD = VDRM RL = 3.3 k TJ = 110C dv/dt (dv/dt)c tgt Lxx04x6 Lxx04x8 5 5 10 3 5 10 20 Unit mA MAX. 1.3 V ALL MIN. 0.2 V MAX. 400V VD = VDRM Gate Open TJ = 100C Lxx04x5 3 ALL IT = 100mA IH MAX. Lxx04x3 TYP. 600V 5 10 10 15 25 25 30 35 15 15 20 25 mA V/s (di/dt)c = 2.16 A/ms TJ = 110C TYP. 0.5 1 1 1 V/s IG = 2 x IGT PW = 15s IT = 5.6 A(pk) TYP. 2.8 3.0 3.0 3.2 s Electrical Characteristics (TJ = 25C, unless otherwise specified) -- Standard Triac Symbol IGT Test Conditions Quadrant VD = 12V RL = 60 VGT VGD VD = VDRM RL = 3.3 k TJ = 125C IH IT = 200mA dv/dt Unit MAX. 10 25 IV TYP. 25 50 I - II - III MAX. 1.3 1.3 MIN. 0.2 0.2 V MAX. 20 30 mA 400V 40 75 600V 30 50 800V VD = VDRM Gate Open TJ = 100C Qxx04x4 I - II - III ALL VD = VDRM Gate Open TJ = 125C Qxx04x3 MIN. 40 1000V mA V V/s 50 (dv/dt)c (di/dt)c = 2.16 A/ms TJ = 125C TYP. 2 2 V/s tgt IG = 2 x IGT PW = 15s IT = 5.6 A(pk) TYP. 2.5 3.0 s Note: xx = voltage, x = package Lxx04xx & Qxx04xx Series 52 Revised: June 24, 2011 04:57 PM (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Static Characteristics (TJ = 25C, unless otherwise specified) Symbol Test Conditions ITM = 5.6A tp = 380 s VTM MAX. Lxx04xy IDRM VDRM = VRRM IRRM MAX. Qxx04xy Value Unit 1.60 V TJ = 25C 400-600V 5 A TJ = 110C 400-600V 200 A TJ = 25C 400-1000V 10 A TJ = 125C 400-800V 2 TJ = 100C 1000V 3 mA Thermal Resistances Symbol Parameter Junction to case (AC) R(J-C) Junction to ambient R(J-A) Value L/Qxx04Dy 3.5 L/Qxx04Ly 3.6 L/Qxx04Ry 3.6 L/Qxx04Vy 6.0 L/Qxx04Ly 50 L/Qxx04Ry 45 L/Qxx04Vy 70 Unit C/W C/W Note: xx = voltage, x = package, y = sensitivity Figure 2: N ormalized DC Gate Trigger Current for All Quadrants vs. Junction Temperature Figure 1: Definition of Quadrants ALL POLARITIES ARE REFERENCED TO MT1 (+) IGT GATE MT1 IGT REF (-) IGT GATE (+) MT1 REF Lxx04xx & Qxx04xx Series MT1 REF QII QI QIII QIV MT2 IGT IGT GATE MT2 + IGT MT2 IGT (TJ = 25C) (-) + 4.0 Ratio of MT2 MT2 POSITIVE (Positive Half Cycle) 3.0 2.0 1.0 IGT GATE 0.0 - MT2 NEGATIVE (Negative Half Cycle) MT1 -65 -40 -40 10 35 60 85 110 Junction Temperature (TJ)- C REF 53 Revised: June 24, 2011 04:57 PM (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. 125 Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Figure 3: Normalized DC Holding Current vs. Junction Temperature Figure 4: N ormalized DC Gate Trigger Voltage for All Quadrants vs. Junction Temperature 2.0 VGT 2.0 VGT (TJ = 25C) 3.0 Ratio of IH Ratio of IH (TJ = 25C) 4.0 1.0 1.5 1.0 0.5 0.0 0.0 -65 -40 -40 10 35 60 85 110 -65 125 -40 -40 Junction Temperature (TJ)- C Figure 5: Power Dissipation (Typical) vs. RMS On-State Current 110 60 85 110 125 CURRENT WAVE FORM: Sinusoidal LOAD: Resistive or Inductive CONDUCTION ANGLE: 360 CASE TEMPERATURE: Measured as shown on Dimensional Drawing 105 Maximum Allowable Case Temperature (TC) - C CURRENT WAVE FORM: Sinusoidal 3.0 35 Figure 6: M aximum Allowable Case Temperature vs. On-State Current 4.0 Average On-State Power Dissipation (PD(AV)) - Watts 10 Junction Temperature (TJ)- C LOAD: Resistive or Inductive CONDUCTION ANGLE: 360 2.0 1.0 100 95 Lxx04Ly Lxx04Dy 90 85 Lxx04Vyz Lxx04Ry LXX04Vy 80 75 70 65 60 0.0 0.0 1.0 2.0 3.0 4.0 0 5.0 1 2 Figure 7: Maximum Allowable Case Temperature vs. On-State Current 4 5 6 Figure 8: Maximum Allowable Ambient Temperature vs. On-State Current 120 110 100 95 Maximum Allowable Ambient Temperature (TA) - C CURRENT WAVE FORM: Sinusoidal LOAD: Resistive or Inductive CONDUCTION ANGLE: 360 CASE TEMPERATURE: Measured as shown on Dimensional Drawing 105 Maximum Allowable Case Temperature (TC) - C 3 RMS On-State Current (IT(RMS)) - Amps RMS On-State Current (IT(RMS)) - Amps Lxx04Ly Lxx04Dy 90 85 Lxx04Vyz Lxx04Ry LXX04Vy 80 75 70 CURRENT WAVEFORM: Sinusoidal LOAD: Resistive or Inductive CONDUCTION ANGLE: 360 FREE AIR RATING - NO HEATSINK 100 80 Qxx04Ly Qxx04Ry 60 L/Qxx04Vy 40 Lxx04Ly 65 20 60 0 1 2 3 4 5 6 RMS On-State Current (IT(RMS)) - Amps 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 RMS On-State Current [IT(RMS)] - Amps Note: xx = voltage, y = sensitivity Lxx04xx & Qxx04xx Series 54 Revised: June 24, 2011 04:57 PM (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. 2.0 Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Figure 9: On-State Current vs. On-State Voltage (Typical) 20 TJ = 25C Positive or Instantaneous On-State Current (IT) - Amps 18 16 14 12 10 8 6 4 2 0 0.6 0.8 1.0 1.2 1.4 1.6 1.8 Positive or Instantaneous On-State Voltage (VT) - Volts Figure 10: Surge Peak On-State Current vs. Number of Cycles Peak Surge (Non-repetitive) On-State Current (ITSM) - Amps 100 Supply Frequency: 60Hz Sinusoidal Load: Resistive RMS On-State [IT(RMS)]: Max Rated Value at Specific Case Temperature Qxx04Ry Qxx04Ly Qxx04Dy Qxx04Vy Notes: 1. G ate control may be lost during and immediately following surge current interval. 2. O verload may not be repeated until junction temperature has returned to steady-state rated value. Lxx04Ry Lxx04Ly Lxx04Dy Lxx04Vy 10 1 1 10 100 1000 Surge Current Duration - Full Cycles Note: xx = voltage, y = sensitivity Lxx04xx & Qxx04xx Series 55 Revised: June 24, 2011 04:57 PM (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Soldering Parameters Pb - Free assembly Pre Heat - Temperature Min (Ts(min)) 150C - Temperature Max (Ts(max)) 200C - Time (min to max) (ts) 60 - 180 secs Average ramp up rate (Liquidus Temp) (TL) to peak 5C/second max TS(max) to TL - Ramp-up Rate 5C/second max Reflow - Temperature (TL) (Liquidus) 217C - Temperature (tL) 60 - 150 seconds 260C +0/-5 Time within 5C of actual peak Temperature (tp) 20 - 40 seconds Ramp-down Rate 5C/second max Time 25C to peak Temperature (TP) 8 minutes Max. Do not exceed 280C Physical Specifications Ramp-up TL tL TS(max) Preheat TS(min) 25 Peak Temperature (TP) tP TP Temperature Reflow Condition tS time to peak temperature Time Environmental Specifications Test Terminal Finish 100% Matte Tin-plated Body Material UL recognized epoxy meeting flammability classification 94V-0 Terminal Material Copper Alloy AC Blocking Temperature Cycling Temperature/ Humidity Design Considerations High Temp Storage Careful selection of the correct device for the application's operating parameters and environment will go a long way toward extending the operating life of the Thyristor. Good design practice should limit the maximum continuous current through the main terminals to 75% of the device rating. Other ways to ensure long life for a power discrete semiconductor are proper heat sinking and selection of voltage ratings for worst case conditions. Overheating, overvoltage (including dv/dt), and surge currents are the main killers of semiconductors. Correct mounting, soldering, and forming of the leads also help protect against component damage. Low-Temp Storage Lxx04xx & Qxx04xx Series Ramp-do Ramp-down 56 Revised: June 24, 2011 04:57 PM Thermal Shock Autoclave Specifications and Conditions MIL-STD-750, M-1040, Cond A Applied Peak AC voltage @ 125C for 1008 hours MIL-STD-750, M-1051, 100 cycles; -40C to +150C; 15-min dwell time EIA / JEDEC, JESD22-A101 1008 hours; 320V - DC: 85C; 85% rel humidity MIL-STD-750, M-1031, 1008 hours; 150C 1008 hours; -40C MIL-STD-750, M-1056 10 cycles; 0C to 100C; 5-min dwell time at each temperature; 10 sec (max) transfer time between temperature EIA / JEDEC, JESD22-A102 168 hours (121C at 2 ATMs) and 100% R/H Resistance to Solder Heat MIL-STD-750 Method 2031 Solderability ANSI/J-STD-002, category 3, Test A Lead Bend MIL-STD-750, M-2036 Cond E (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Dimensions -- TO-220AB (R-Package) -- Non-Isolated Mounting Tab Common with Center Lead TC MEASURING POINT AREA (REF.) 0.17 IN2 O A E Dimension 8.13 .320 P MT2 B C 13.36 .526 D 7.01 .276 NOTCH IN GATE LEAD TO ID. NON-ISOLATED TAB F R G L H K N J Note: Maximum torque to be applied to mounting tab is 8 in-lbs. (0.904 Nm). M MT1 MT2 GATE Inches Millimeters Min Max Min Max A 0.380 0.420 9.65 10.67 B 0.105 0.115 2.67 2.92 C 0.230 0.250 5.84 6.35 D 0.590 0.620 14.99 15.75 E 0.142 0.147 3.61 3.73 F 0.110 0.130 2.79 3.30 G 0.540 0.575 13.72 14.61 H 0.025 0.035 0.64 0.89 J 0.195 0.205 4.95 5.21 K 0.095 0.105 2.41 2.67 L 0.060 0.075 1.52 1.91 M 0.085 0.095 2.16 2.41 N 0.018 0.024 0.46 0.61 O 0.178 0.188 4.52 4.78 P 0.045 0.060 1.14 1.52 R 0.038 0.048 0.97 1.22 Min Max Min Max Dimensions -- TO-220AB (L-Package) -- Isolated Mounting Tab TC MEASURING POINT O A E P AREA (REF.) 0.17 IN2 Dimension 8.13 .320 B C 13.36 .526 D 7.01 .276 F R G L H K N J MT1 MT2 GATE Lxx04xx & Qxx04xx Series M Note: Maximum torque to be applied to mounting tab is 8 in-lbs. (0.904 Nm). 57 Revised: June 24, 2011 04:57 PM Inches Millimeters A 0.380 0.420 9.65 10.67 B 0.105 0.115 2.67 2.92 C 0.230 0.250 5.84 6.35 D 0.590 0.620 14.99 15.75 E 0.142 0.147 3.61 3.73 F 0.110 0.130 2.79 3.30 G 0.540 0.575 13.72 14.61 H 0.025 0.035 0.64 0.89 J 0.195 0.205 4.95 5.21 K 0.095 0.105 2.41 2.67 L 0.060 0.075 1.52 1.91 M 0.085 0.095 2.16 2.41 N 0.018 0.024 0.46 0.61 O 0.178 0.188 4.52 4.78 P 0.045 0.060 1.14 1.52 R 0.038 0.048 0.97 1.22 (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Dimensions -- TO-251AA (V-Package) -- V-PAK Through Hole TC MEASURING POINT E MT2 AREA: 0.040 IN2 H D Dimension 5.28 .208 J A 5.34 .210 B R P Q S K C MT1 L F MT2 GATE G I Inches Millimeters Min Typ Max Min Typ Max A 0.040 0.044 0.050 1.02 1.11 1.27 B 0.235 0.242 0.245 5.97 6.15 6.22 C 0.350 0.361 0.375 8.89 9.18 9.53 D 0.205 0.208 0.213 5.21 5.29 5.41 E 0.255 0.262 0.265 6.48 6.66 6.73 F 0.027 0.031 0.033 0.69 0.80 0.84 G 0.087 0.090 0.093 2.21 2.28 2.36 H 0.085 0.092 0.095 2.16 2.34 2.41 I 0.176 0.180 0.184 4.47 4.57 4.67 J 0.018 0.020 0.023 0.46 0.51 0.58 K 0.038 0.040 0.044 0.97 1.01 1.12 L 0.018 0.020 0.023 0.46 0.52 0.58 P 0.042 0.047 0.052 1.06 1.20 1.32 Q 0.034 0.039 0.044 0.86 1.00 1.11 R 0.034 0.039 0.044 0.86 1.00 1.11 S 0.074 0.079 0.084 1.86 2.00 2.11 Dimensions -- TO-252AA (D-Package) -- D-PAK Surface Mount MT2 E D 6.71 .264 5.28 .208 TC MEASURING POINT Dimension 6.71 .264 B C P Q MT1 GATE F MT2 1.60 .063 1.80 .071 AREA : 0.040 IN2 3 .118 G 4.60 .181 I O L K J H M N Lxx04xx & Qxx04xx Series 58 Revised: June 24, 2011 04:57 PM Millimeters Min Typ Max Min Typ Max A 0.040 0.043 0.050 1.02 1.09 1.27 B 0.235 0.243 0.245 5.97 6.16 6.22 C 0.106 0.108 0.113 2.69 2.74 2.87 A 5.34 .210 Inches D 0.205 0.208 0.213 5.21 5.29 5.41 E 0.255 0.262 0.265 6.48 6.65 6.73 F 0.027 0.031 0.033 0.69 0.80 0.84 G 0.087 0.090 0.093 2.21 2.28 2.36 H 0.085 0.092 0.095 2.16 2.33 2.41 I 0.176 0.179 0.184 4.47 4.55 4.67 J 0.018 0.020 0.023 0.46 0.51 0.58 K 0.038 0.040 0.044 0.97 1.02 1.12 L 0.018 0.020 0.023 0.46 0.51 0.58 M 0.000 0.000 0.004 0.00 0.00 0.10 N 0.021 0.026 0.027 0.53 0.67 0.69 O 0 0 5 0 0 5 P 0.042 0.047 0.052 1.06 1.20 1.32 Q 0.034 0.039 0.044 0.86 1.00 1.11 (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs Product Selector Part Number Voltage Gate Sensitivity Quadrants Type Package 3 mA Sensitive Triac TO-220L 3 mA 3 mA Sensitive Triac TO-252 D-PAK X 3mA 3mA Sensitive Triac TO-220R X X 3 mA 3 mA Sensitive Triac TO-251 V-PAK Lxx04L5 X X 5 mA 5 mA Sensitive Triac TO-220L Lxx04D5 X X 5 mA 5 mA Sensitive Triac TO-252 D-PAK Lxx04R5 X X 5mA 5mA Sensitive Triac TO-220R Lxx04V5 X X 5 mA 5 mA Sensitive Triac TO-251 V-PAK Lxx04L6 X X 5 mA 10 mA Sensitive Triac TO-220L Lxx04D6 X X 5 mA 10 mA Sensitive Triac TO-252 D-PAK Lxx04R6 X X 5mA 10mA Sensitive Triac TO-220R Lxx04V6 X X 5 mA 10 mA Sensitive Triac TO-251 V-PAK Lxx04L8 X X 10 mA 20 mA Sensitive Triac TO-220L Lxx04D8 X X 10 mA 20 mA Sensitive Triac TO-252 D-PAK Lxx04R8 X X 10mA 20mA Sensitive Triac TO-220R Lxx04V8 X X 10 mA 20 mA Sensitive Triac TO-251 V-PAK Qxx04L3 X X 10 mA Standard Triac TO-220L Qxx04D3 X X 10 mA Standard Triac TO-252 D-PAK Qxx04V3 X X 10 mA Standard Triac TO-251 V-PAK Qxx04R3 X X 10mA Standard Triac TO-220R Qxx04L4 X X X X 25 mA Standard Triac TO-220L Qxx04D4 X X X X 25 mA Standard Triac TO-252 D-PAK Qxx04R4 X X X X 25mA Standard Triac TO-220R Qxx04V4 X X X X 25 mA Standard Triac TO-251 V-PAK 400V 600V Lxx04L3 X Lxx04D3 800V 1000V I - II - III IV X 3 mA X X Lxx04R3 X Lxx04V3 Packing Options Part Number L/Q004L/Ry/TP L/Qxx04LyTP Marking Weight Packing Mode Base Quantity L/Qxx04L/Ry 2.2 g Bulk 500 L/Qxx04Ly 2.2 g Tube 500 (50 per tube) L/Qxx04DyRP L/Qxx04Dy 0.3 g Embossed Carrier 2500 L/Qxx04DyTP L/Qxx04Dy 0.3 g Tube Pack 750 (75 per tube) L/Qxx04VyTP L/Qxx04Vy 0.4 g Tube Pack 750 (75 per tube) Note: xx = Voltage; y = Sensitivity Lxx04xx & Qxx04xx Series 59 Revised: June 24, 2011 04:57 PM (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information. Teccor(R) brand Thyristors 4 Amp Sensitive & Standard Triacs TO-252 Embossed Carrier Reel Pack (RP) Specifications Meets all EIA-481-2 Standards * Cover tape 0.315 (8.0) MT1 XXXXXX DC 0.059 DIA (1.5) XX DC XX XXXXXX * XX 0.524 (13.3) XXXXXX 0.63 (16.0) DC Gate XXXXXX 0.157 (4.0) MT2 12.99 (330.0) 0.512 (13.0) Arbor Hole Dia. Dimensions are in inches (and millimeters). 0.64 (16.3) Direction of Feed Part Numbering System Part Marking System Q 60 04 L 4 xx LEAD FORM DIMENSIONS xx : Lead Form Option DEVICE TYPE L : Sensitive Triac Q : Standard Triac PACKAGE TYPE L :TO-220 Isolated R :TO-220 Non-Isolated V :TO-251 (V-Pak) D :TO-252 (D-Pak) (R) L6004V4 (R) SENSITIVITY & TYPE Sensitive Triac: 3 : 3 mA (QI, II, III, IV) 5 : 5 mA (QI, II, III, IV) 6 : 5 mA (QI, II, III) 10 mA (QIV) 8 : 10 mA (QI, II, III) 20 mA (QIV) Standard Triac: 3 : 10 mA (QI, II, III) 4 : 25 mA (QI, II, III) (R) CURRENT RATING 04 : 4A Q6004R4 YM YMLDD VOLTAGE RATING 40 : 400V 60 : 600V 80 : 800V K0 : 1000V TO-251AA & TO-252AA (V and D Packages) Q6004L4 MY (R) (R) Lxx04xx & Qxx04xx Series 60 Revised: June 24, 2011 04:57 PM (c)2011 Littelfuse, Inc Specifications are subject to change without notice. Please refer to http://www.littelfuse.com for current information.