A Comment about Power Supply Design Software

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There is an abundance of software-based power supply design tools, particularly for PWM switching power supply designs. Many of these software packages were written by the semiconductor manufacturers for their own highly integrated switching power supply integrated circuits (ICs). Many of these ICs include the power devices as well as the control circuitry. These types of software packages should only be used with the targeted products and not for general power supply designs. The designs presented by these manufacturers are optimized for minimum cost, weight, and design time, and the arrangements of any external components are unique to that IC.

There are several generalized switching power supply design software packages available primarily from circuit simulator companies. Caution should be practiced in reviewing all software-based switching power supply design tools. Designers should compare the results from the software to those obtained manually by executing the appropriate design equations. Such a comparison will enable designers to determine whether the programmer and his or her company really understands the issues surrounding switching power supply design.
Remember, most of the digital world thinks that designing switching power supplies is just a matter of copying schematics. The software packages may also obscure the amount of latitude a designer has during a power supply design. By making the program as broad in its application as possible, the results may be very conservative. To the seasoned designer, this is only a first step. He or she knows how to “push” the result to
enhance the power supply’s performance in a certain area. All generally applied equations and software results should be viewed as calculated estimates. In short, the software may then lead the designer to a result that works but is not optimum for the system.