SPICE

Document 267
SPICE Model – MVR
This lumped-element (SPICE) model data simulates the
frequency-dependent behavior of Coilcraft power inductors within the frequency range shown in the accompanying table for each individual inductor.
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 other
production verification instruments and fixtures.
vidual lumped element values may be erroneous.
The value of the frequency-dependent variable resistor
RVAR1 is calculated from:
RVAR1 = k1 *
• k1 is shown for each value in the accompanying table.
• f is the frequency in Hz
• RVAR1 is the resistance in Ohms
The value of the frequency-dependent variable resistor
RVAR2 is calculated from:
RVAR2 = k2 *
Lumped Element Modeling Method
Measurements were made using a 50 Ohm impedance
analyzer. Fixture compensation was performed to remove fixture effects. No DC bias current was applied in
any of the measurements. The lumped element values
were determined by optimizing 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 equivalent lumped element model schematic is
shown below. Each model should be analyzed only at
the input and output ports. Conclusions based on indi-
• k2 is shown for each value in the accompanying table.
• f is the frequency in Hz
• RVAR2 is the resistance in Ohms
The value of the frequency-dependent inductance LVAR
is calculated from:
LVAR = k3 − k4
* LOG (k5 * f)
• k3, k4, and k5 are shown in the accompanying table.
• f is the frequency in Hz
• LVAR is the inductance in µH
Disclaimer
RVAR2
VAR
C
R2
RVAR1
VAR
R1
LVAR
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. 2006
Document 267-1 Revised 02/19/03
Document 267
SPICE Model for Coilcraft MVR Power Inductors
Part number
MVR1251T-251
MVR1251T-361
MVR1251T-561
MVR1247C-361
MVR1255C-651
MVR1261C-112
MVR1271C-162
MVR1278C-232
Frequency limit
of model (MHz)
Lower Upper
0.1
200
0.1
200
0.1
200
0.1
100
0.1
100
0.1
100
0.1
100
0.1
70
LVAR Coefficients
⏲)
R1 (⏲
100
85
200
300
300
300
300
240
⏲)
R2 (⏲
9.25E-04
9.25E-04
9.25E-04
9.25E-04
1.50E-03
1.95E-03
2.53E-03
3.08E-03
C (pF)
1.68
1.66
1.64
3.06
2.90
2.63
2.78
4.30
k1
1.50E-05
8.00E-06
1.00E-05
1.80E-05
2.20E-05
2.50E-05
3.50E-05
4.50E-05
k2
0.087
0.058
0.070
0.046
0.088
0.14
0.20
0.30
k3
0.250
0.360
0.560
0.360
0.650
1.10
1.65
2.30
Specifications subject to change without notice.
© Coilcraft, Inc. 2006
k4
4.00E-03
8.00E-03
1.50E-02
2.10E-02
2.50E-02
4.40E-02
5.60E-02
7.00E-02
k5
9.80E-06
9.80E-06
9.80E-06
9.80E-06
9.80E-06
9.80E-06
9.80E-06
9.80E-06
Document 267-55 Revised 11/16/06