STEVAL-250GANCB

STEVAL-250GANCB is a high efficiency 24V – 250W power adapter board based on GaN and digital control. This AC/DC power adapter consists of 3 stages: totem pole PFC (AC/DC) working in zero voltage switching, variable frequency mode; resonant half bridge LLC converter (DC-DC) and a synchronous rectification output stage. The solution uses a single MCU STM32G474RE to control the PFC and primary side of LLC. The synchronous rectification stage is controlled by SRK2001 and 2 parallel STL120N10F8 STripFET F8 power MOSFETs. The totem pole PFC operates in ZVS with variable switching in the range of 35 ÷ 300kHz, from light load to full load. The LLC implements frequency modulation to regulate O/P voltage and operates at variable frequency from 200 to 300kHz, with resonance frequency of 227kHz. The startup phase is performed at high frequency from 500 down to 200k/Hz. Excellent switching performance of GaN devices at high frequency and the soft switching techniques (ZCS and ZVS) in all stages.

• Topology: ZVS Totem Pole PFC + HB LLC with SR
• GaN based power stage
• Digital control based on a single STM32G474 MCU
• 250W output rated power
• Input voltage range Vin from 115 to 230V AC
• Peak efficiency is 96% at full load, 230V AC
• Power density is greater than 1W/cm³ (17 W/in³)
• No load consumption less than 150mW