An example of a static model (left) and dynamic mode (right) of a chip inductor.

The dynamic model is close to the measured value.

Murata began providing dynamic circuit simulation models of chip inductors and multilayer ceramic capacitors. Previously, the company provided static models.

In the static model, the characteristics of the parts do not change even if the current flowing in the corresponding parts and the applied voltage change. This time, the dynamic model that we began to provide is different, and we can reproduce changes in the characteristics that result from changes in current and voltage values.

The dynamic model of the chip inductor provided this time can reproduce the DC superposition characteristics. The DC superposition characteristic means that in an inductor having a ferromagnetic body (ferrite, etc.) as its inner core, the inductance changes with the magnitude of the current flowing. When a large current flows, the ferromagnetic body becomes nearly magnetically saturated, and the permeability decreases accordingly, thereby exhibiting DC superposition characteristics.

The chip inductors that provide a dynamic model are the 83 models of the "LQM Series". The target circuit simulators are "PSpice" and "Spectre" of Cadence Design Systems, "HSPICE" of Synopsys, and "LTspice" of Linear Technology of the United States. ".

The dynamic model of the multilayer ceramic capacitor provided this time can reproduce the DC bias characteristic. The DC bias characteristic means that in a high dielectric constant ceramic capacitor, the electrostatic capacitance changes with the applied DC voltage. When the applied DC voltage is applied to a high dielectric constant ceramic capacitor, the dielectric constant changes and the DC bias characteristic is exhibited.

The laminated ceramic capacitors that provide a dynamic model are 2531 models such as "GRM Series", "GJx Series" and "LLx Series". The target circuit simulators are "PSpice" and "Spectre" of the US Quantum Design System, "HSPICE" of Synox Technology, and "LTspice" of Linear Technology of the United States.

From June 23, 2015, all dynamic models can be downloaded from Murata's website. (Reporter: Yutaro Kojima)

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