Power modules are essential components in various applications such as electric vehicle charging stations, clean energy systems, variable speed drives, and IT equipment power supplies. The design and development of these power modules are challenging, particularly for project managers who are looking to optimize power provision while minimizing cost, design time, and unexpected results. One of the most significant challenges of power module design is the use of gate drivers to control semiconductor power switches. This article discusses the current design challenges in power module development and innovative solutions to minimize them.
Gate driver options are extensive, and the design challenges continue well beyond the selection of the driver, particularly when it comes to switch bias power sources. Switches need a bias power source to supply the gate power, which often demands the use of multiple power supplies isolated from the controlled ground. Designing these power supplies takes up valuable engineering time, and adding components to the design increases the cost, size, and complexity of the power module, both in the design and the bill of materials. Moreover, the added complexity increases the risk of unexpected results during design validation and in application.
Conventional gate drivers also typically use a bootstrap circuit to create the floating voltage required for controlling the high-side switches. Choosing the optimal combination of components for this circuit can be challenging. An easier design process would be to use a gate driver that also supplies the power needed to control the switches and a single capacitor to create the floating voltage for the high-side switches.
Fortunately, a solution has emerged that eliminates the need for external power supplies and simplifies the design process while reducing cost and complexity. Allegro MicroSystems developed the Power-Thru technology, which includes a single, novel magnetic coupling device within the integrated circuit that transfers the gate on/off logic signal with the power needed to drive the gate of the switch, eliminating the need for external auxiliary power. The complete electrical isolation provided by their magnetic coupling makes Power-Thru gate drivers ideal for use in high-side, low-side, and isolated applications alike.
Allegro Power-Thru technology uses magnetic coupling to deliver switching power with logic, eliminating the need for external auxiliary power supplies and achieving smaller system size, fewer components, and reduced cost. The Power-Thru gate drivers eliminate the need for auxiliary power supplies, which can reduce BOM costs, system size and build complexity, recoup engineering design time, improve the likelihood of early success in testing and validation, and increase reliability in application.
Unique design and construction make the Allegro Power-Thru gate drivers easy to use: The need to specify only a single capacitor can further reduce design time and improve the likelihood of early design success. When compared to conventional solutions, the Allegro Power-Thru gate drivers can deliver significant cost savings, design simplification, and reliability and performance improvements in all aspects of power module construction.
In summary, the development of power modules is a complex and challenging task that requires careful attention to cost, design time, and unexpected results. The use of gate drivers to control semiconductor power switches is one of the most significant challenges in power module design. However, innovative solutions such as the Power-Thru technology from Allegro MicroSystems can eliminate the need for external power supplies and simplify the design process while reducing cost and complexity, improving reliability, and increasing performance.
