DC-DC
This application note discusses the design of a 1.5 kW, two-phase 48 V/12 V bi-directional converter using automotive qualified GaN FETs that operates with 95% efficiency. The heatsinking capability can be considered infinite since this will ultimately function inside a vehicle with the unit mounted to the chassis. The design of this converter is scalable to 3 kW by paralleling two converters.
Brick DC-DC converters are widely used in data center, telecommunication and automotive applications, converting a nominal 48 V bus to (or from) a nominal 12 V bus. Advances in GaN integrated circuit (IC) technology have enabled the integration of the half bridge and gate drivers, resulting in a single chip solution that simplifies layout, minimizes area, and reduces cost.
As computers, displays, smart phones and other consumer electronics systems become thinner and more powerful, addressing the challenge of thinning the power converter and getting more power out of limited space without increasing the surface temperature increases in demand. This application note will look into designing a 44 V to 60 V input, 12 V to 20 V, 12.5 A output, thin DC/DC power module with low temperature rise using eGaN FETs in the simple and low-cost synchronous buck topology.
Brick DC-DC converters are widely used in data center, telecommunication and automotive applications, converting a nominal 48 V to a nominal 12 V distribution bus among other output voltages. The main trend has been towards higher power density given the form factor is fixed. This application note discusses the design of a digitally controlled 1/16th brick converter using GaN FETs for a 48 V to 12 V, 9 V, 5 V application, with up to 25 A output current, 300 W output power, a peak efficiency of 95.8%, and maximum power density of 730 W/in3.
Over the past decade, DC-to-DC power modules in datacom, telecom, and consumer electronics systems demand more power with increasing limitations on space and volume, requiring ultra-thin and highly efficient solutions. The multi-level converter is an exceptional candidate to shrink the size of the magnetic components and achieve high efficiency in a compact solution.
The rapid expansion of the computing and telecommunication market is demanding an ever more compact, efficient and high power density solution for intermediate bus converters. The LLC resonant converter is a remarkable candidate to provide a high power density and high efficiency solution. eGaN FETs with their ultra-low on-resistance and parasitic capacitances, benefit LLC resonant converters by significant loss reduction that is challenging when using Si MOSFETs.
The rapid expansion of the computing and telecommunication market is demanding an ever more compact, efficient and high power density solution for intermediate bus converters. The LLC resonant converter is a remarkable candidate to provide a high power density and high efficiency solution. eGaN FETs with their ultra-low on-resistance and parasitic capacitances, benefit LLC resonant converters by significant loss reduction that is challenging when using Si MOSFETs.
Single-phase buck converter can work efficiently at output currents up to 25 A, but the power efficiency drops significantly at higher currents. A compact, cost effective, high-power and high-efficiency 48 V to 12 V buck converter, suitable for high-power computing and telecommunication applications, can be achieved by employing eGaN FETs such as EPC2045 in a multiphase topology.
The smallest, most cost effective, highest efficiency and 25 A capable non-isolated 48 V to 5-12V converter, suitable for high-performance computing and telecommunication applications, can be accomplished by employing eGaN® FETs such as the EPC2053. The EPC9093 GaN development board configured as a synchronous buck converter yields a main power stage area of only 10 mm x 9 mm, at least 2x smaller than its Si equivalent, and is capable of producing an output voltage ranging from 5 V to 12 V.
The smallest, most cost effective and highest efficiency non-isolated 48 V to 12 V converter, suitable for high-performance computing and telecommunication applications, can be achieved by employing eGaN® FETs such as the EPC2045. The EPC9205 configured as a synchronous Buck converter yielded a power density of 1400 W/in3 and is capable of delivering 15 A.
The smallest, most cost effective and highest efficiency non-isolated 12 V to 1.0 V POL converter, suitable for high-performance computing, cryptocurrency and telecommunication applications, can be achieved by employing monolithic eGaN® IC half-bridges such as the EPC2111. The EPC9204 configured as a synchronous Buck converter yielded a power density of 1000 W/in3 and is capable of delivering 12 A.
Lidar
Light Detection and Ranging (Lidar) is a remote sensing technology which transmits pulses of light from the sensor and measures the reflection to determine the location and distance of objects. The extremely high performance of GaN and the ultra-low inductance of the chip-scale package make eGaN FETs the ideal switches for pulsed laser drivers.
Motor Drive
Brushless DC (BLDC) motors are popular and finding increasing application in robotics, e-mobility, and drones. Such applications have special requirements such as lightweight, small size, low torque ripple, and precision control. To address these needs, inverters powering the motors need to operate at higher frequency, but require advanced techniques to reduce the resultant higher power loss.
AC/DC
The expansion of applications such as cloud computing, wearables, machine learning, autonomous driving, and IoT drive us towards an even more data-intensive world, increasing demands on data centers and power consumption [1, 2]. The importance of efficiency, power density, and cost of the AC to DC switching power supply is driving innovative solutions that eGaN FETs can solve to yield ultra-high efficiency power factor correction (PFC) front-end rectifier solutions that are the focus of this how-to-application note.
Design
eGaN FET-based power conversion systems offer higher efficiency, increased power density, and lower overall system cost than Si-based alternatives. These advantageous characteristics have spurred the presence of an ever increasing ecosystem of power electronics components such as gate drivers, controllers, and passive components that specifically enhance eGaN FET performance.
eGaN FETs are capable of switching much faster than Si MOSFETs, requiring more careful consideration of PCB layout design to minimize parasitic inductances. Parasitic inductances cause higher overshoot voltages and slower switching transitions. This application note reviews the key steps to design an optimal power stage layout with eGaN FETs, to avoid these unwanted effects and maximize the converter performance.
EPC’s wafer level chip-scale packaging such as the Land Grid Array (LGA) and Ball Grid Array (BGA) packages shown in figure 1, has enabled a new level of performance in power conversion. Many of these parts use a fine pitch down to 400 μm which means a proper PCB footprint design is essential for consistent and reliable assembly of the GaN device. Here are the guidelines of designing a correct footprint for any EPC part working from the datasheet.
EPC’s innovative wafer level, Land Grid Array (LGA) and Ball Grid Array (BGA) packaging has enabled a new level of performance in power conversion. Proper assembly techniques are essential to take full advantage of GaN technology capability. Here are the guidelines for manual assembly of these FETs and ICs.
eGaN FETs and ICs enable very high-density power converter design, owing to their compact size, ultra-fast switching, and low on-resistance. The limiting factor for output power in most high-density converters is junction temperature, which prompts the need for more effective thermal design. The chip-scale packaging of eGaN also offers six-sided cooling, with effective heat extraction from the bottom, top, and sides of the die. This application note presents a high-performance thermal solution to extend the output current capability of eGaN-based converters.
Advancements in eGaN FET-based converters’ in-circuit capability drives high performance measurement requirements. This article compares various measurement techniques and technologies’ capability of accurately evaluating high performance eGaN FETs in applications.