How to use online design tools to shorten the power supply design process

　　As product life cycles become shorter and shorter, system design engineers must consider power integration as early as possible during system design to avoid major revisions at the final stage. In order to obtain a better system design, design engineers can use online design tools for power circuits to shorten the front-end processing and even the complete design time.

　　The competitive pressure in the market forces the development time of new generation products to become shorter and shorter. Those who enter the market later will usually lose business opportunities and market share.

　　Among them, the load point power management circuit faces challenges such as constantly changing processor units, smaller form factors, higher performance, and faster operating frequencies. Therefore, the product life cycle is very short, making it impossible for system design engineers to separate the power supply design from the overall system structure. If power integration is not considered early, resources may be over-consumed and the product design must be significantly revised in the final stage.

　　In order to obtain better power density, efficiency and flexibility of distributed power architecture, system design engineers must also consider the circuit design of the power supply in order to obtain the best electrical performance, integration and reliability performance of the product.

　　In power circuit design, as emerging designs become more and more complex and specialized, the demand for simulation tools is increasing. Before the introduction of circuit simulation tools, engineers had to perform time-consuming calculations by hand, spend a lot of time on architectural prototype design, and repeatedly compare laboratory measurements with calculation results to make corrections. Therefore, when faced with urgent design deadlines, many engineers are often forced to use previous designs for incremental modifications instead of adopting the latest technology.

　　Online design tools for power circuits can assist circuit designers in completing projects in many different ways. Some tools aim to shorten the front-end processing by comparing and selecting chips and topologies, while others provide simulation support for already designed circuit diagrams. Ideally, tools that support design engineers in designing should cover the entire design cycle.

　　Complete solutions go mainstream

　　Semiconductor manufacturers have begun to adopt a solution-based approach to simplify and accelerate the design of power management circuits for low-power systems. Take the myPOWER online design center of International Rectifier (IR) as an example (Figure 1), which includes a series of power semiconductors, passive components and inductors for specific power levels, and provides reference designs that have been fully tested and classified with characteristics to predict electrical and temperature performance with optimized circuit board layout arrangements. Unlike common analog circuit boards, these reference designs reflect the actual circuit conditions as much as possible, providing effective solutions to complex problems such as circuit board layout, temperature design, and component matching optimization.

　　Using the operating parameters, temperature conditions and functional requirements input by the design engineer, this design tool can calculate the circuit loss, provide circuit board layout, airflow arrangement and ambient temperature, and accurately estimate the junction temperature of key components. This series of calculations will be repeated on the appropriate reference design in the database to find the best design and provide calculated efficiency, junction temperature, circuit board layout arrangement and bill of materials (BOM) cost, so that the design engineer can compare all the data and obtain the best solution selection that meets the design goals.

　　Each reference design is paired with a full set of online simulation tools. Simulation capabilities include small-signal and large-signal analysis, switching waveforms, and performance analysis of all components. Design engineers are provided with a complete schematic with a complete bill of materials including manufacturer part numbers and estimated prices. This schematic is interactive and comes with a library of different alternative parts that engineers can use to adjust the design as needed.

　　This simulation capability can save development time by verifying component stresses, component values, and circuit connections before ordering prototype functional demonstration boards. All values ​​can be changed and re-evaluated in seconds rather than replacing components and re-soldering, saving a lot of time.

　　When customizing a standard reference design, users can adjust system-level inputs to trade off key performance criteria such as electrical efficiency, power dissipation, junction temperature, size, and bill of materials cost. Once completed, the entire circuit can be re-simulated immediately, eliminating the cost and time of replacing parts for design engineers and giving them the freedom to make a large number of design changes. After the design engineer has verified that the selected reference design meets the requirements, performance testing can be performed to confirm that the entire design can operate and that the measured results are consistent with the calculated values ​​provided by the online tool (Figure 2).

　　For example, the design support team of International Rectifier adopts a solution-oriented approach to provide reference design circuit boards that meet the customized requirements of online users. Each customized circuit board is tested for specifications and can generate design files that can be directly applied to embedded applications. These tested customized reference design kits will be verified against the results obtained online, allowing users to start system-level performance testing.

　　Circuit Design Automation

　　Many chips designed for specific applications are designed with extensive application notes in the datasheet when using other passive and active components. Although the expertise contained in the document is of great reference value to engineers, it still takes hours or even days to complete all the calculations and match the results with the available components. This time-consuming and annoying task can become a major obstacle to the adoption of new topology technology, and the learning curve is also long. Therefore, in this type of circuit design, an online design tool that can perform all the necessary calculations will help save a lot of time.

　　For example, International Rectifier’s single-cycle control power factor correction (PFC) design tool starts with a basic circuit diagram and then lets the design engineer specify input and output parameters used to calculate passive component values, reducing the hours of manual calculations to seconds. It also allows the design engineer to quickly analyze waveforms and optimize the design for individual needs.

　　The results of the automated analysis include a complete bill of materials (Figure 3) and a table of output conditions describing the circuit’s performance. The tool also generates graphs showing the AC line resonant distortion, output ripple voltage, overall loop response, and error amplifier response (Figure 4). All data is provided as a PDF file for easy integration into a design engineer’s personal design notebook.

　　In the best case, such online tools can provide information about high-density, low-cost PFC control circuits, allowing design engineers to directly replace existing power supplies and replace old continuous conduction mode PFC circuits without spending too much valuable time on repeated performance testing.

　　Save time and create greater benefits

　　Directly quoting a proven design is the easiest way for design engineers to design power circuits for new systems. Unfortunately, old power designs may not meet the needs of new systems and also hinder the adoption of newer and improved chips and switches that can improve performance.

　　Of course, engineers can also generate new designs through old methods such as building prototypes and repeating testing procedures, but this is not an easy task for system design engineers who specialize in the digital field, and engineers do not have extra time.

　　Simulation is a good way for design engineers to find and correct problems without actually building a prototype, and it can also speed up the design process. However, good simulation programs are quite expensive, and good circuit models must be prepared, which is also very time-consuming for engineers who are not familiar with software or circuits. However, the production of prototypes is still necessary because the accuracy of most simulation results is not enough to compete with good designs.

　　The combination of design tools and the Internet has accelerated circuit design and prototype manufacturing. In recent years, as electronic design has become increasingly complex and costly, the demand for simulation tools has become increasingly urgent. Today's design engineers must use the latest technology as much as possible to design smaller and more efficient power conversion devices. Online simulation and supply system tool software not only helps save time, but also ensures a stable design with a prototype that can run and related supporting test data. Through high-speed simulation, mature design platforms, and fully assembled and tested reference design circuit boards, design engineers will be able to obtain effective end-to-end design solutions early in the entire development process.