23 August 2022
BRC Solar selects EPC2218 100V eGaN FETs for solar power optimizer
Efficient Power Conversion Corp (EPC) of El Segundo, CA, USA – which makes enhancement-mode gallium nitride on silicon (eGaN) power field-effect transistors (FETs) for power management applications – says that its EPC2218 100V FETs have been designed into the next-generation M500/14 power optimizer of BRC Solar GmbH of Ettlingen Germany. This has enabled a higher current density due to the low power dissipation and the small size of the GaN FET making the critical load circuit more compact. The small parasitic capacitance and inductance of the GaN FETs creates a clean switching performance, which allows good EMI behavior in the field. Another benefit of the GaN FETs is the zero reverse recovery losses.
The EPC2218 is a 100V GaN FET, 3.2mΩ, 231Apulsed, with a small footprint of just 3.5mm x 1.95mm, offering lower losses and smaller size than comparable silicon MOSFETs for increased power density.
BRC’s previous range, the M400/12, handled currents up to 12A and maximum power operation at 400W. By changing from Si FETs to GaN FETs the company achieved an increase in output current to 14A with a power rating of 500W – while keeping the same board size. Also, the switching frequency in the M500/14 is twice as high as the previous generation, allowing for passive components such as capacitors and inductors to be decreased in value or even completely removed.
BRC’s optimizer is only active when shading on the photovoltaic module appears. The predominant case is a fully irradiated module, where the circuit goes into an inactive state. The switching FET is continuously closed in this situation. It is important that the power losses on the board be kept as low as possible. It is reckoned that the EPC2218 is hence the optimal solution for BRC’s application because of its low RDS(on). The static losses are also extremely small due to the excellent conductivity of the GaN FET.
During the active mode the switching behavior of the module optimizer leads to a small and acceptable power loss. The low parasitic components of the EPC2218 enable fast and clean switching in the application.
In both modes, the temperature rise of the FET is small and allows good thermal transfer to the board via the LGA pads of the EPC2218 even at higher ambient temperatures, says EPC. Therefore, an additional heat-sink is not required, further saving space and weight.
“Working with BRC has been an exciting design-in opportunity and, together with our distribution partner Finepower, we have been able to achieve great results, moving the company from silicon to GaN,” says Stefan Werkstetter, EPC’s VP of sales, EMEA. “Designers using GaN can now take advantage of devices that are higher performance, smaller, more thermally efficient, and at a comparable cost.”