Gallium nitride Technology (GAN) has long been nothing new in the application of LED. The original intention of Gan development was to be born for LED. Later, researchers began to explore RF, power and other fields based on the high-frequency characteristics of GaN.
Up to now, Gan is still mainly used at the light source end and not widely used in the power system. Talking about the reasons, Jason Yan, senior technical training manager of PI, said that the industry began to carry out the industrialization research of the third generation wide band gap semiconductor more than ten years ago, but the yield of Gan or SiC is very low, so the cost is very high. At the same time, the application of Gan is still very difficult, because it is a high-speed device, PCB layout is very sensitive, and EMI design is very difficult. PI puts all design challenges into the chip through the integrated way, which increases the reliability of the product and reduces the design difficulty, making it possible for a large number of market-oriented applications of Gan technology.
Not long ago, PI held a press conference in Beijing, introduced Pi’s new generation powigan technology, and officially introduced Gan switch into Pi’s flyback switching power supply IC series.
Powigan technology has been widely used
In 2018, the fast charging products adopting PI Gan scheme have been put into mass production. At present, none of the materials have failed and returned to the factory, which fully proves the high reliability of the products. At the same time, the excellent efficiency of Gan switch has also been recognized by the market.
Yan Jinguang particularly stressed that Pi’s powigan technology adopts a single-chip scheme, and all processes are developed by PI itself. It is a completely proprietary technology and will not be used by other manufacturers. At the same time, in terms of supply chain, PI also selects a long-term and stable OEM partner to ensure the stability and reliability of products.
PI CEO Balu Balakrishnan said in the quarterly report teleconference: “GaN based innoswitch devices have excellent efficiency and achieve a power density level that silicon switches cannot achieve. Although we initially focused on these new products as high-power chargers for mobile devices, Gan will play an important role in Pi’s Roadmap in the next few years. We plan to launch a series of new products to bring Gan’s excellent performance characteristics to a wider range of applications 。”
Gan assisted compact high power LED
As Balu said, within a few days of announcing the launch of powigan technology, PI announced that powigan? Technology is put into lytswitch-6 series safety isolated LED Driver IC, which can realize the design of up to 110 W output power and 94% conversion efficiency through simple and flexible flyback topology.
As shown in the figure, lyt6079 and 6070 adopt powigan technology to achieve an output level of more than 100W without heat sink through higher efficiency, which is tens of Watts higher than other products in the same series. “The product is very suitable for smart home and commercial lighting and thin Ceiling Recessed lamp applications. The high-power density lytswitch-6 design can reduce the height and weight of LED driver, which is very important for space limited and closed ballast applications,” said Hubie notohamiprodjo, marketing director of PI LED lighting products.
Yan Jinguang added that due to the higher withstand voltage of Gan technology, compared with traditional silicon process products, it has a higher service life and is very suitable for key applications such as lighting drive, which are not easy to install.
Same high integration as lytswitch-6
In addition to changing the switch from Si to Gan, the whole chip has no other changes, which is consistent with the innoswitch of powigan technology developed by PI. This is also the tradition of PI. Previously, fluxlink technology, which Pi is proud of, is also widely used in innoswitch and lytswitch.
As shown in the figure, in addition to powigan, lytswitch-6 series also has eight advantages, which can realize a higher integration of primary side and secondary side without optocoupler isolation, significantly reduce system power consumption, improve efficiency, ensure device stability and reliability, and reduce the overall cost of the system.
The new lytswitch-6 IC is extremely efficient and does not require the use of heat sinks – significantly reducing the size and weight of the ballast and reducing the requirements for the air-cooled environment around the drive. 750 V powigan primary switch provides very low RDS (on) and reduces switching loss. Compared with the conventional scheme, this improvement, combined with many existing characteristics of lytswitch-6, can increase the power conversion efficiency by 3%, and then reduce the waste of heat energy by more than one third.
Lytswitch-6 IC adopts powigan technology to provide lossless current detection, which helps to improve efficiency. The new devices of lytswitch-6 product series still retain the advantages of fast dynamic response, which can provide excellent cross adjustment rate for parallel LED lamp strings, without additional secondary voltage stabilizing circuit, and support the operation of flicker free system. These advantages can ensure that it is easier to realize dimming applications using pulse width modulation (PWM) interface.
Yan Jinguang added that the high-power LED driving system including PFC circuit is realized through Pi’s integrated MOSFET hiperpfs-4pfc controller and qspeed boost diode as power factor correction and lytswitch. According to the measured results given by pi, the efficiency exceeds 90%.
Despite the fierce battle in the LED drive market, Gan technology may be used for applications with high power and requirements for size and efficiency, which can significantly reflect the product differentiation, just as the changes taking place in the adapter market.