Document 298 SPICE Model – 1008PS This lumped-element (SPICE) model data simulates the frequency-dependent behavior of Coilcraft ferrite surface mount inductors within the frequency range shown in the accompanying table. The equivalent lumped element model schematic is shown below. The element values R1, R2, C, L, k1 and k2 are listed in the table for each component value. The value of the frequency-dependent variable resistor RVAR1 relates to the skin effect and is calculated from: RVAR1 = k1 * • k1 is shown for each value in the accompanying table. • f is the frequency in Hz The value of the frequency-dependent variable resistor RVAR2 relates to core losses and is calculated from: RVAR2 = k2 * • • k2 is shown for each value in the accompanying table. f is the frequency in Hz element model compared to the measurements taken of the component. Typically, the Self-Resonant Frequency (SRF) of the component model will be higher than the measurement of the component mounted on a circuit board. The parasitic reactive elements of a circuit board or fixture will effectively lower the circuit resonant frequency, especially for very small inductance values. Since data sheet specifications are based on typical production measurements, and the SPICE models are based on de-embedded measurements as described below, the model results may be different from the data sheet specifications. Lumped Element Modeling Method Measurements were made using a 50 Ohm Agilent/ HP 4395A impedance analyzer with an Agilent/HP 16193 test fixture. Calibration was performed using open/short/ load standards. Fixture compensation was performed using open and short standards. The lumped element values were determined by matching the simulation model to an average of the measurements. This method results in a model that represents as closely as possible the typical frequency-dependent behavior of the component within the model frequency range. The lumped element models were used to generate our 2-port S-parameters and therefore give identical results. The S-parameters are available on our web site at http://www.coilcraft.com/models.cfm. The data represents de-embedded measurements, as described below. Effects due to different customer circuit board traces, board materials, ground planes or interactions with other components are not included and can have a significant effect when comparing the simulation to measurements of the inductors using typical production verification instruments and fixtures. Each model should only be analyzed at the input and output ports. Individual elements of the model are not determined by parameter measurement. The elements are determined by the overall performance of the lumped Disclaimer Coilcraft makes every attempt to provide accurate measurement data and software, representative of our components, in a usable format. Coilcraft, however, disclaims all warrants relating to the use of its data and software, whether expressed or implied, including without limitation any implied warranties of merchantability or fitness for a particular purpose. Coilcraft cannot and will not be liable for any special, incidental, consequential, indirect or similar damages occurring with the use of the data and/ or software. Specifications subject to change without notice. © Coilcraft, Inc. 2009 Document 298-1 Revised 11/13/02 Document 298 SPICE Model for Coilcraft 1008PS Power Inductors Part number 1008PS-102 1008PS-152 1008PS-182 1008PS-272 1008PS-392 1008PS-472 1008PS-562 1008PS-682 1008PS-103 1008PS-153 1008PS-223 1008PS-333 1008PS-393 1008PS-473 1008PS-683 1008PS-823 1008PS-104 1008PS-124 1008PS-154 1008PS-224 1008PS-334 1008PS-474 1008PS-564 1008PS-684 1008PS-824 1008PS-105 Frequency limit of model (MHz) Lower Upper 0.1 50 0.1 45 0.1 40 0.1 30 0.1 30 0.1 25 0.1 20 0.1 16 0.1 12 0.1 10 0.1 9 0.1 9 0.1 8 0.1 8 0.1 7 0.1 6 0.1 4 0.1 4 0.1 3.5 0.1 4 0.1 2 0.1 1.8 0.1 1.5 0.1 1.3 0.1 1 0.1 1.2 R1 1210 1470 2300 1790 3380 4270 5220 4990 8980 2880 2670 1920 1790 1010 559 506 553 594 462 488 521 642 726 1150 1150 1520 R2 0.061 0.178 0.120 0.120 0.267 0.307 0.369 0.470 0.880 1.25 1.76 2.20 2.02 2.99 4.17 4.20 5.39 6.48 6.68 9.29 10.7 15.1 16.0 22.1 25.1 28.6 C (pF) 540 600 600 861 503 552 552 5.13 2.73 3.28 2.98 2.95 3.74 3.47 3.48 4.36 4.52 4.79 5.69 3.63 5.80 5.80 6.15 4.84 4.24 5.36 L (µH) 1.0 1.5 1.8 2.7 3.9 4.7 5.6 6.8 10 15 22 33 39 47 68 82 100 120 150 220 330 470 560 680 819 999 Specifications subject to change without notice. © Coilcraft, Inc. 2009 k1 9.96E-06 8.35E-06 4.64E-05 1.97E-05 1.12E-05 1.54E-06 2.36E-06 1.18E-05 1.18E-05 1.78E-05 2.73E-05 2.81E-05 3.60E-05 3.97E-05 4.75E-05 6.44E-05 1.26E-04 1.97E-04 2.91E-04 4.65E-04 4.99E-04 5.13E-04 3.87E-04 6.95E-04 1.14E-03 1.40E-03 k2 0.655 4.22 2.11 3.37 27.0 51.0 204 6.35 12.7 18.8 27.1 41.0 41.4 56.3 71.7 77.0 97.9 111 123 172 196 251 323 403 504 568 Document 298-4 Revised 02/05/03