Document 833-1 Coupled Inductors – LPD6235 For Flyback and other Applications Tight coupling (k ≥ 0.97) makes the LPD6235 series of coupled inductors ideal for use in a variety of circuits including flyback, multi-output buck, SEPIC and Zeta. These coupled miniature shielded inductors are 3.5 mm high and 6.0 mm square. They provide high inductance, high efficiency and excellent current handling in low cost part. They can be used as two single inductors connected in series or parallel, as a common mode choke or as a 1 : 1 transformer. + + D L1 C L2 VOUT C VIN – SW – 0.236 ±0.003 6,0 ±0,08 Typical Flyback Converter L2 Dot indicates pin 1 1 D + VOUT C AUX – 4 XXX X 2 Dash number + 0.236 ±0.003 6,0 ±0,08 + VIN 3 L1 D SW – – Typical Buck Converter with auxiliary output Internal code D + 0.138 max 3,5 4 0.047 1,20 0.167 0.079 4,25 2,00 45° typ 0.260 6,60 C + C1 L2 Q – C + Q – VOUT – Typical SEPIC schematic + VIN 0.079 2,00 0.167 4,25 0.260 6,60 0.079 2,00 2 VIN 3 2 L1 L1 Recommended Land Pattern 1 1 VOUT C C L2 C1 L1 D Typical Zeta schematic C VOUT – 4 Dimensions are in L2 inches mm 3 Document 833-1 Revised 11/09/15 Document 833-2 Coupled Inductors – LPD6235 Series Part number1 Inductance ±20% (µH) LPD6235-682MR_ LPD6235-103MR_ LPD6235-223MR_ LPD6235-473MR_ LPD6235-104MR_ 6.8 10 22 47 100 LPD6235-474MR_ LPD6235-105MR_ LPD6235-155MR_ LPD6235-205MR_ 2 470 1000 1500 2000 DCR max3 (Ohms) 0.120 0.157 0.300 0.620 1.20 3.50 7.00 10.8 16.0 SRF typ4 (MHz) Coupling Leakage5 coefficient L typ typ (µH) 31 26 15 9.7 7.0 0.99 0.99 >0.99 >0.99 >0.99 0.10 0.12 0.15 0.21 0.45 3.0 1.9 1.5 1.3 >0.99 >0.99 >0.99 >0.99 0.61 1.05 1.70 2.10 1. Please specify termination and packaging codes: LPD6235-205MRC Termination: R = RoHS compliant matte tin over nickel over silver. Special order: Q = RoHS tin-silver-copper (95.5/4/0.5) or P = non-RoHS tin-lead (63/37). Packaging: C = 7″ machine-ready reel. EIA-481 embossed plastic tape (350 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 (1500 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. Leakage inductance is for L1 and is measured with L2 shorted. 6. DC current at 25°C that causes the specified inductance drop from its value without current. It is the sum of the current flowing in both windings. 7. Equal current when applied to each winding simultaneously that causes a 40°C temperature rise from 25°C ambient. This information is for reference only and does not represent absolute maximum ratings. 8. Maximum current when applied to one winding that causes a 40°C temperature rise from 25°C ambient. This information is for reference only and does not represent absolute maximum ratings. 9. 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. 10% drop 2.80 2.50 1.50 0.90 0.62 0.18 0.12 0.12 0.08 Isat (A)6 Irms (A) 20% 30% both one drop drop windings7 winding8 3.00 3.12 1.40 1.98 2.70 2.80 1.30 1.83 1.67 1.73 0.85 1.20 0.98 0.99 0.60 0.85 0.72 0.74 0.40 0.56 0.22 0.14 0.12 0.11 0.23 0.15 0.13 0.12 0.25 0.15 0.14 0.11 0.35 0.21 0.20 0.16 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. Core material Ferrite Weight 420 – 480 mg Environmental RoHS compliant, halogen free Terminations RoHS compliant matte tin over nickel over silver. Other terminations available at additional cost. Ambient temperature –40°C to +85°C with (40°C rise) Irms current. Maximum part temperature +125°C (ambient + temp rise). Storage temperature Component: –40°C to +125°C. Tape and reel 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 350/7″ reel; 1500/13″ reel Plastic tape: 16 mm wide, 0.3 mm thick, 12 mm pocket spacing, 3.68 mm pocket depth Recommended pick and place nozzle OD: 6.2 mm; ID: ≤ 3.1 mm PCB washing Tested to MIL-STD-202 Method 215 plus an additional aqueous wash. See Doc787_PCB_Washing.pdf. Document 833-2 Revised 11/09/15 Document 833-3 Coupled Inductors – LPD6235 Series L vs Current L vs Frequency 10000 10000 2000 µH 1500 µH 1000 µH 470 µH 100 100 µH 47 µH 22 µH 10 1 470 µH Current (A) 47 µH 22 µH 10 µH 6.8 µH 1 1 0.1 100 µH 100 10 10 µH 6.8 µH 0.01 1500 µH 1000 µH 1000 Inductance (µH) Inductance (µH) 1000 2000 µH 10 0.1 1 10 100 Frequency (MHz) Document 833-3 Revised 11/09/15