Document 580-1 Coupled Inductors–LPD4012 For SEPIC and other Applications The LPD4012 coupled miniature shielded inductors are only 1,1 mm high and 4 mm square. Their excellent coupling coefficient (k ≥ 0.94) makes them ideal for use in SEPIC applications. In SEPIC topologies, the required inductance for each winding in a coupled inductor is half the value needed for two separate inductors, allowing selection of a part with lower DCR and higher current handling. These inductors provide high efficiency and excellent current handling in a rugged, low cost part. They can also be used as two single inductors connected in series or parallel, as a common mode choke or as a 1 : 1 transformer. 0.155 ±0.003 3,94 ±0,076 D1 + Dot indicates pin 1 1 4 XXX X 2 Dash number VIN 0.155 ±0.003 3,94 ±0,076 3 Recommended Land Pattern 4 0.031 0,78 0.103 0.049 2,606 1,24 4 45° typ 0.174 4,40 3 2 0.060 1,52 + Load VOUT – 0.049 1,24 0.103 2,606 0.174 4,40 L2 3 Dimensions are in inches mm Core material Ferrite Core and winding loss See www.coilcraft.com/coupledloss Weight 54 – 64 mg Terminations RoHS compliant silver-palladium-platinum-glass frit. Other terminations available at additional cost. Ambient temperature –40°C to +85°C with Irms current, +85°C to +125°C with derated current Storage temperature Component: –40°C to +125°C. Packaging: –40°C to +80°C Winding to winding isolation 100 V Resistance to soldering heat Max three 40 second reflows at +260°C, parts cooled to room temperature between cycles Moisture Sensitivity Level (MSL) 1 (unlimited floor life at <30°C / 85% relative humidity) Failures in Time (FIT) / Mean Time Between Failures (MTBF) 38 per billion hours / 26,315,789 hours, calculated per Telcordia SR-332 Packaging 1000/7″reel; 3500/13″ reel Plastic tape: 12 mm wide, 0.25 mm thick, 8 mm pocket spacing, 1.32 mm pocket depth Recommended pick and place nozzle OD: 4 mm; ID: ≤ 2 mm PCB washing Only pure water or alcohol recommended Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2010 C2 Typical SEPIC schematic 1 2 L2 Q1 Refer to Application Note, Document 639, “Selecting Coupled Inductors for SEPIC Applications” 0.0433 ±0.004 1,10 ±0,10 L1 C1 – Internal code 1 + L1 Document 580-1 Revised 09/18/09 Document 580-2 Coupled Inductors for SEPIC Applications – LPD4012 Series Irms (A) both one windings6 winding7 DCR max3 (Ohms) LPD4012-331NL_ LPD4012-561NL_ LPD4012-821NL_ LPD4012-152ML_ LPD4012-222ML_ 0.33 ±30% 0.56 ±30% 0.82 ±30% 1.5 ±20% 2.2 ±20% 0.042 0.087 0.100 0.134 0.176 255 185 130 86 70 5.2 3.7 3.2 2.6 2.3 5.4 3.8 3.3 2.7 2.4 5.6 3.9 3.4 2.8 2.5 1.87 1.30 1.21 1.05 0.91 2.65 1.84 1.72 1.48 1.29 LPD4012-332ML_ LPD4012-472ML_ LPD4012-562ML_ LPD4012-682ML_ LPD4012-822ML_ 3.3 ±20% 4.7 ±20% 5.6 ±20% 6.8 ±20% 8.2 ±20% 0.242 0.370 0.467 0.500 0.545 48 39 32 31 29 1.8 1.6 1.5 1.3 1.1 1.9 1.7 1.6 1.4 1.2 2.0 1.8 1.6 1.5 1.3 0.78 0.63 0.56 0.54 0.52 1.10 0.89 0.79 0.77 0.74 Part number1 SRF typ4 (MHz) Isat (A)5 10% drop 20% drop 30% drop Inductance2 (µH) LPD4012-103ML_ LPD4012-153ML_ LPD4012-223ML_ LPD4012-333ML_ LPD4012-473ML_ 10 ±20% 15 ±20% 22 ±20% 33 ±20% 47 ±20% 0.638 0.940 1.52 1.74 2.20 25 21 15 12 8.8 0.98 0.79 0.74 0.45 0.35 1.0 0.82 0.78 0.47 0.37 1.1 0.84 0.79 0.48 0.38 0.48 0.40 0.31 0.29 0.26 0.68 0.56 0.44 0.41 0.37 LPD4012-683ML_ LPD4012-823ML_ LPD4012-104ML_ LPD4012-124ML_ LPD4012-154ML_ 68 ±20% 82 ±20% 100 ±20% 120 ±20% 150 ±20% 3.19 3.41 4.76 5.20 6.90 7.8 7.3 6.1 5.3 4.6 0.30 0.26 0.24 0.23 0.21 0.32 0.28 0.26 0.24 0.22 0.33 0.30 0.27 0.25 0.23 0.21 0.21 0.18 0.17 0.15 0.30 0.29 0.25 0.24 0.21 LPD4012-184ML_ LPD4012-224ML_ LPD4012-334ML_ LPD4012-474ML_ LPD4012-564ML_ 180 ±20% 220 ±20% 330 ±20% 470 ±20% 560 ±20% 7.90 9.80 15.12 20.90 22.10 4.1 3.3 2.8 2.3 2.1 0.18 0.150 0.140 0.100 0.090 0.19 0.16 0.145 0.110 0.105 0.20 0.17 0.150 0.120 0.115 0.14 0.12 0.10 0.08 0.08 0.19 0.17 0.14 0.12 0.12 Temperature rise calculation based on specified Irms 1. Please specify termination and packaging codes: LPD4012-564MLC Termination: L = RoHS compliant Silver-palladium-platinum-glass frit. Special order: T = RoHS tin-silver-copper (95.5/4/0.5) or S = non-RoHS tin-lead (63/37). Packaging: C = 7″ machine-ready reel. EIA-481 embossed plastic tape (1000 parts per full reel). B = Less than full reel. In tape, but not machine ready. To have a leader and trailer added ($25 charge), use code letter D instead. D = 13″ machine-ready reel. EIA-481 embossed plastic tape. Factory order only, not stocked (3500 parts per full reel). 2. Inductance shown for each winding, measured at 100 kHz, 0.1 Vrms, 0 Adc on an Agilent/HP 4284A LCR meter or equivalent. When leads are connected in parallel, inductance is the same value. When leads are connected in series, inductance is four times the value. 3. DCR is for each winding. When leads are connected in parallel, DCR is half the value. When leads are connected in series, DCR is twice the value. 4. SRF measured using an Agilent/HP 4191A or equivalent. When leads are connected in parallel, SRF is the same value. 5. DC current, at which the inductance drops the specified amount from its value without current. It is the sum of the current flowing in both windings. 6. Equal current when applied to each winding simultaneously that causes a 40°C temperature rise from 25°C ambient. See temperature rise calculation. 7. Maximum current when applied to one winding that causes a 40°C temperature rise from 25°C ambient. See temperature rise calculation. 8. Electrical specifications at 25°C. Refer to Doc 639 “Selecting Coupled Inductors for SEPIC Applications.” Refer to Doc 362 “Soldering Surface Mount Components” before soldering. Winding power loss = (IL12 + IL22 ) × DCR in Watts (W) 135°C Temperature rise = Winding power loss × W Examples for LPD4012-152ML: Equal current in each winding (1.05 A): Winding power loss = (1.05 2 + 1.05 2) × 0.134 = 0.296 W Temperature rise = 0.296 W × 135°C = 40°C W Unequal current (IL1 = 1.3 A, IL2 = 0.7 A): Winding power loss = (1.3 2 + 0.7 2) × 0.134 = 0.292 W 135°C = 39.4°C Temperature rise = 0.292 W × W Coupled Inductor Core and Winding Loss Calculator This web-based utility allows you to enter frequency, peak-to-peak (ripple) current, and Irms current to predict temperature rise and overall losses, including core loss. Visit www.coilcraft.com/coupledloss. Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2010 Document 580-2 Revised 09/18/09 Document 580-3 Coupled Inductors for SEPIC Applications – LPD4012 Series Typical L vs Current Typical L vs Frequency 1000 1000 330 µH 330 µH 100 µH 33 µH 10 µH 10 100 µH 100 Inductance (µH) Inductance (µH) 100 3.3 µH 1.5 µH 33 µH 10 µH 10 3.3 µH 1.5 µH 1 1 0.33 µH 0.33 µH 0.1 0.1 0.01 1 0.1 10 0.1 1 10 100 Frequency (MHz) Current (A) Typical Current Derating 120 110 90 80 70 60 50 40 30 20 25°C Percent of rated current 100 Isat Irms 10 0 -40 -20 0 20 40 60 80 100 120 140 Ambient temperature (°C) Specifications subject to change without notice. Please check our website for latest information. © Coilcraft, Inc. 2010 Document 580-3 Revised 09/18/09